Add features and run agent

[improdead]

PR Type

Enhancement, Tests, Documentation

---

Description

Major production-ready feature implementation across five key areas:

• Background Worker System: Complete rewrite of generate.worker.ts with dual-queue architecture (pages and characters), Supabase image uploads, AI rendering (Gemini/OpenAI), Redis event publishing, and graceful shutdown handling

• Queue Management: Enhanced BullMQ Redis queue service with dual queues, job prioritization (characters > pages), queue statistics, pause/resume capabilities, and admin controller with monitoring endpoints

• Planner Hardening: Comprehensive error handling with custom error types, exponential backoff retry logic, Zod input validation, JSON extraction/repair strategies, and fallback stub outline generation

• Export Functionality: New export service supporting PDF and CBZ (comic book archive) formats with image embedding, metadata, ZIP compression, and optional audio inclusion

• Observability Stack: Complete implementation of Sentry + OpenTelemetry + Pino logging with:

  • Structured logging service with trace context injection
  • OpenTelemetry tracing with Sentry integration
  • Request correlation interceptor for distributed tracing
  • Cost calculation utilities and performance budget tracking
  • API observability wrapper for Next.js
  • Alert rules configuration for monitoring

• Database Enhancements: Prisma schema updates with audio support, strategic indexes for query optimization, seed data with sample episodes, and comprehensive error handling wrapper

• Module Integration: Episodes service now integrates queue-based generation with transaction support; all modules properly configured with dependency injection

• Documentation: Extensive guides covering observability setup, database management, queue implementation, export features, and architecture verification with health scoring

• Testing: Database operations test script, observability validation script, and test endpoints for system verification

---

Diagram Walkthrough

flowchart LR
  A["Episodes Service"] -- "queue jobs" --> B["BullMQ Queues"]
  B -- "page/character jobs" --> C["Background Worker"]
  C -- "upload images" --> D["Supabase Storage"]
  C -- "AI rendering" --> E["Gemini/OpenAI"]
  C -- "publish events" --> F["Redis Pub/Sub"]
  F -- "forward events" --> G["SSE EventsService"]
  G -- "real-time updates" --> H["Frontend Clients"]
  A -- "export episodes" --> I["Export Service"]
  I -- "generate files" --> J["PDF/CBZ Output"]
  K["Planner Service"] -- "validate/retry/fallback" --> L["AI Planning"]
  M["All Services"] -- "structured logging" --> N["Pino Logger"]
  M -- "tracing spans" --> O["OpenTelemetry"]
  O -- "error tracking" --> P["Sentry"]
  M -- "correlation IDs" --> Q["Request Tracing"]
  R["Prisma ORM"] -- "error handling" --> S["Custom Error Handler"]
  R -- "persist data" --> T["PostgreSQL"]

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File Walkthrough

	Relevant files
Enhancement	25 files generate.worker.ts Complete background worker implementation with dual queues and AI rendering backend/src/worker/generate.worker.ts Complete rewrite from simple placeholder to production-ready background worker with comprehensive documentation Implements dual-queue architecture for page and character generation with configurable concurrency levels Adds WorkerStorageService for Supabase image uploads with fallback to placeholder URLs Adds WorkerRendererService supporting both Gemini and OpenAI image generation with proper error handling Implements Redis event publishing for real-time progress updates and job status tracking Adds graceful shutdown handling with proper resource cleanup +481/-25 episodes.service.ts Integrate background queue system with error handling and transactions backend/src/episodes/episodes.service.ts Adds Logger and QueueService dependencies for background job processing Wraps database operations with withPrismaErrorHandling and withPrismaTransaction for better error resilience Implements conditional queue-based vs in-process generation for pages and characters Adds transaction support for atomic episode, page, and character creation Improves error handling with try-catch blocks and detailed logging +252/-128 planner.service.ts Harden planner service with retries, validation, and fallback strategies backend/src/planner/planner.service.ts Adds comprehensive error handling with custom error types (PlannerValidationError, PlannerJsonExtractionError, PlannerApiError) Implements retry logic with exponential backoff via withRetry utility Adds input validation using Zod schemas Implements JSON extraction and repair strategies with fallback to stub outlines Adds metrics tracking for success rates, retry attempts, and error categorization Integrates observability services for logging and tracing +269/-120 planner.service.hardened.ts Add hardened planner service variant with console logging backend/src/planner/planner.service.hardened.ts New file containing hardened version of planner service with console-based logging Implements same retry, validation, and fallback logic as main planner service Provides alternative implementation for environments without structured logging +386/-0  export.service.ts Add manga export service supporting PDF and CBZ formats    backend/src/export/export.service.ts New service for exporting manga episodes in PDF and CBZ (comic book archive) formats Implements exportAsPDF with image embedding and metadata support Implements exportAsCBZ with ZIP compression, ComicInfo.xml metadata, and optional audio inclusion Includes image and audio download utilities with timeout handling Provides filename sanitization and temporary directory cleanup +309/-0  planner.utils.ts Add planner utilities for retries, JSON handling, and metrics backend/src/planner/planner.utils.ts New utility module with retry logic, JSON extraction/repair, and error formatting Implements withRetry with exponential backoff for resilient API calls Provides extractAndRepairJson with six different extraction strategies Adds formatZodError for readable validation error messages Includes PlannerMetrics class for tracking success rates and error types +311/-0  queue.service.ts Enhance queue service with dual queues and management capabilities backend/src/queue/queue.service.ts Refactors to support dual queues: generate:page and generate:character with separate concurrency Adds typed job data interfaces (GeneratePageJobData, GenerateCharacterJobData) Implements job priority system with characters having higher priority than pages Adds queue management methods: getQueueStats, cleanQueues, pauseQueues, resumeQueues Improves job tracking with unique job IDs and detailed logging +186/-11 planner.fallback.ts Add planner fallback with stub outline generation                backend/src/planner/planner.fallback.ts New fallback module providing stub outline generation when AI fails Implements generateStubOutline to create valid 10-page outlines from seed data Adds mergeWithStub to combine partial AI output with stub data for resilience Includes filename sanitization for character assets +182/-0  instrumentation-helpers.ts Add observability helpers for costs, performance, and error tracking backend/src/observability/instrumentation-helpers.ts New module with AI cost calculation utilities and performance budget tracking Defines cost estimates for OpenAI and Gemini models Implements error categorization for better observability and Sentry integration Provides performance budget checking for manga operations Includes helper functions for span attributes and error metadata extraction +181/-0  tracing.service.ts Add OpenTelemetry tracing service with Sentry integration backend/src/observability/tracing.service.ts New service for OpenTelemetry tracing integration with Sentry support Implements traceAsync and trace methods for wrapping operations with spans Adds specialized tracing for AI API calls and manga operations Provides span attribute management and event recording Integrates with Sentry for error capture and transaction tracking +205/-0  api-wrapper.ts Frontend API observability wrapper with Sentry integration lib/observability/api-wrapper.ts Wraps Next.js API routes with Sentry error tracking and performance monitoring Generates/extracts correlation IDs for request tracing Logs structured JSON with latency metrics and error details Provides helper functions for tracking manga operations and performance +198/-0  schemas.ts Zod validation schemas for manga planning pipeline              backend/src/planner/schemas.ts Defines Zod validation schemas for episode planning and character generation Validates cast members, dialogues, page outlines, and episode seeds Enforces constraints on page numbers, panel counts, and character names Exports TypeScript types inferred from schemas for type safety +128/-0  logger.service.ts Structured logging service with Pino and OpenTelemetry      backend/src/observability/logger.service.ts NestJS-compatible logger service using Pino for structured logging Supports JSON output in production and pretty-printed logs in development Injects OpenTelemetry trace context (trace_id, span_id) automatically Provides specialized methods for logging AI metrics and manga generation events +160/-0  queue-events-bridge.service.ts Redis pub/sub bridge for worker event streaming                    backend/src/queue/queue-events-bridge.service.ts Bridges Redis pub/sub worker events to SSE EventsService for real-time updates Monitors BullMQ job lifecycle events (active, completed, failed, progress) Forwards worker events to frontend clients via Server-Sent Events Provides static helper for workers to publish events to the bridge +117/-0  queue.controller.ts Queue administration controller with monitoring endpoints backend/src/queue/queue.controller.ts Admin API endpoints for queue monitoring and management Provides endpoints to get stats, pause/resume queues, clean old jobs Allows querying individual job details and canceling jobs Includes health check endpoint for queue status +123/-0  episodes.controller.ts Episode export endpoint for PDF and CBZ formats                    backend/src/episodes/episodes.controller.ts Added POST /episodes/:id/export endpoint for PDF/CBZ export functionality Validates format parameter and checks episode has generated pages Filters pages with images and sorts by page number Returns binary file with appropriate Content-Type and Content-Disposition headers +72/-2    instrumentation.ts OpenTelemetry and Sentry initialization module                      backend/src/instrumentation.ts Initializes Sentry and OpenTelemetry before application startup Configures OTLP trace exporter for distributed tracing Sets up auto-instrumentation for HTTP, database, and external calls Includes graceful shutdown handler for SDK cleanup +90/-0    correlation.interceptor.ts Request correlation interceptor for distributed tracing    backend/src/observability/correlation.interceptor.ts NestJS interceptor that generates/extracts correlation IDs from requests Adds correlation ID to response headers for request tracing Logs all HTTP requests with method, URL, status, and latency Captures errors with full context for debugging +72/-0    main.ts Backend entry point with observability initialization        backend/src/main.ts Loads instrumentation module before any other imports (critical for OpenTelemetry) Adds correlation ID headers to CORS configuration Initializes Sentry error handling for NestJS Maintains existing port discovery and startup logic +9/-1      app.module.ts NestJS app module with observability and export                    backend/src/app.module.ts Imports ObservabilityModule as first module for global availability Adds ExportModule for PDF/CBZ export functionality Maintains all existing modules in proper dependency order Ensures observability interceptors apply to all routes +14/-1    observability.module.ts Global observability module for NestJS                                      backend/src/observability/observability.module.ts Global NestJS module providing LoggerService and TracingService Registers CorrelationInterceptor as APP_INTERCEPTOR for all routes Exports services for dependency injection across application Enables automatic request correlation and tracing +19/-0    queue.module.ts Queue module with event bridge and admin controller            backend/src/queue/queue.module.ts Imports EventsModule for SSE event streaming Registers QueueEventsBridgeService for worker event forwarding Exports QueueService for use in other modules Adds QueueController for admin API endpoints +6/-1      planner.module.ts Planner module with observability integration                        backend/src/planner/planner.module.ts Imports ObservabilityModule for logging and tracing Enables PlannerService to use LoggerService and TracingService Maintains existing PlannerService provider and exports +2/-0      export.module.ts Export module for PDF and CBZ generation                                  backend/src/export/export.module.ts New module providing ExportService for PDF/CBZ export functionality Exports service for use in episodes module Minimal configuration for export feature +8/-0      schema.prisma Prisma schema updates with audio support and indexes          backend/prisma/schema.prisma Added audioUrl field to Page model for audio narration storage Added database indexes on createdAt, updatedAt, status, and composite keys Optimized query performance with strategic index placement Maintains cascade delete relationships for data integrity +8/-0
Configuration changes	6 files seed.ts Add Prisma database seed with sample manga episodes            backend/prisma/seed.ts New database seed file with sample episode and character data Creates two complete episodes with pages, characters, and outlines for testing Includes realistic manga content with cyberpunk and school-life themes Provides placeholder image URLs for development and testing +281/-0  episodes.module.ts Add queue and export modules to episodes module                    backend/src/episodes/episodes.module.ts Adds QueueModule and ExportModule to module imports Enables background job processing and export functionality for episodes +3/-1      sentry.client.config.ts Sentry configuration for Next.js client-side                          sentry.client.config.ts Configures Sentry for browser-side error tracking and performance monitoring Enables session replay and browser tracing integration Filters out health check errors and browser extension errors Extracts correlation IDs from response headers for breadcrumb tracking +58/-0    sentry.server.config.ts Sentry configuration for Next.js server-side                          sentry.server.config.ts Configures Sentry for Next.js server-side rendering Enables performance monitoring for SSR operations Filters out health check errors Integrates HTTP instrumentation for server-side requests +27/-0    sentry.edge.config.ts Sentry configuration for Next.js Edge Runtime                        sentry.edge.config.ts Minimal Sentry configuration for Next.js Edge Runtime Enables performance monitoring with configurable sample rates Filters out health check errors Supports production and development environments +13/-0    migration_lock.toml Prisma migration lock file                                                              backend/prisma/migrations/migration_lock.toml Migration lock file for PostgreSQL provider Ensures consistent migration state across environments Prevents concurrent migration conflicts +3/-0
Tests	3 files test-db.ts Database operations test script for Prisma validation        backend/prisma/test-db.ts Comprehensive database operations test script with 10 test cases Tests CRUD operations, relationships, transactions, and cascade deletes Validates database connection and indexes with real Prisma queries Includes episode, page, and character creation and verification +187/-0  test-observability.ts Observability system test and validation script                    backend/src/observability/test-observability.ts Test script validating logger, tracing, and error handling functionality Tests AI metrics logging, manga operation tracing, and async operations Verifies error handling and provides instructions for checking Sentry/Jaeger Runnable with npx ts-node src/observability/test-observability.ts +140/-0  observability-test.ts Frontend observability test endpoint                                          pages/api/observability-test.ts Test API endpoint for validating observability setup Tracks manga operations and logs performance metrics Returns correlation ID and tips for checking Sentry/Jaeger Accessible at http://localhost:3000/api/observability-test +48/-0
Error handling	1 files prisma-error-handler.ts Prisma error handling with custom error types                        backend/src/prisma/prisma-error-handler.ts Custom error handler for Prisma operations with user-friendly messages Maps Prisma error codes (P2002, P2003, P2025, etc.) to descriptive messages Supports fallback values and transaction error handling Provides withPrismaErrorHandling and withPrismaTransaction wrappers +88/-0
Documentation	10 files OBSERVABILITY_IMPLEMENTATION_SUMMARY.md Complete observability implementation documentation            OBSERVABILITY_IMPLEMENTATION_SUMMARY.md Comprehensive 842-line documentation of observability implementation Details Sentry, OpenTelemetry, Pino logging, and correlation tracking Includes setup instructions, testing procedures, and troubleshooting Documents cost tracking, performance budgets, and alert recommendations +842/-0  ARCHITECTURE_VERIFICATION_REPORT.md Architecture verification and integration report                  ARCHITECTURE_VERIFICATION_REPORT.md 694-line architecture review identifying critical build failure Documents dual architecture issue between NestJS and Next.js Provides integration matrix and module dependency verification Includes health score (72/100) and actionable recommendations +694/-0  EXPORT_FEATURE.md PDF and CBZ export feature documentation                                  EXPORT_FEATURE.md 409-line documentation for PDF/CBZ export feature Details file formats, implementation, usage examples, and testing Includes performance considerations and known limitations Provides deployment notes and troubleshooting guide +409/-0  OBSERVABILITY.md Complete observability implementation guide with architecture and setup OBSERVABILITY.md Comprehensive observability guide (615 lines) covering Sentry, OpenTelemetry, Pino logging, and custom metrics Architecture diagrams showing frontend/backend integration with observability backends Complete setup instructions for Sentry, Jaeger, Honeycomb, and Grafana Cloud Usage examples for instrumenting services, tracking AI calls, and monitoring performance budgets Recommended alerts, SLOs, cost tracking, and troubleshooting guide +615/-0  FEATURES_IMPLEMENTATION_SUMMARY.md Summary of five major production-ready features implementation FEATURES_IMPLEMENTATION_SUMMARY.md Executive summary of 5 production-ready features implemented in parallel Detailed breakdown of each feature: Prisma persistence, BullMQ queueing, planner hardening, PDF/CBZ export, Sentry+OTEL observability Environment setup template with all required variables Deployment checklist, testing instructions, and performance impact analysis Success metrics showing 40+ files created, 20+ modified, 8,300+ lines added +625/-0  OBSERVABILITY_IMPLEMENTATION_REPORT.txt Observability implementation final report with metrics and setup OBSERVABILITY_IMPLEMENTATION_REPORT.txt Final implementation report for observability stack (528 lines) Details on 22 files created/modified (17 backend, 5 frontend) NPM packages added (~20 packages for Sentry, OpenTelemetry, Pino) Custom metrics and traces for manga operations and AI API calls Alert rules, monitoring setup options, testing instructions, and production readiness checklist +528/-0  ARCHITECTURE_VISUAL_SUMMARY.txt Architecture verification report with build failure analysis ARCHITECTURE_VISUAL_SUMMARY.txt Visual architecture verification report with 72/100 health score Critical build failure identified: frontend cannot parse @Injectable() decorators from backend imports Feature implementation status: all 5 features marked as passing Module dependency map showing NestJS architecture with proper DI Action items prioritized from P0 (critical) to P2 (medium) +346/-0  IMPLEMENTATION_SUMMARY.md Planner hardening with validation, retries, and fallback strategies backend/src/planner/IMPLEMENTATION_SUMMARY.md Comprehensive planner hardening implementation summary (525 lines) Zod schema definitions for input/output validation with strict rules Retry logic with exponential backoff (3 attempts, 1-10 second delays) 6 JSON extraction strategies and repair functionality Fallback strategies: partial merge and stub outline generation Environment variables, testing instructions, and performance characteristics +525/-0  DATABASE_SETUP.md PostgreSQL database setup and management guide with schema details backend/DATABASE_SETUP.md Complete PostgreSQL + Prisma setup guide (443 lines) Database schema documentation for Episode, Page, and Character models Step-by-step installation for PostgreSQL and Prisma migrations Database management commands (Prisma Studio, reset, migrations) Error handling, transaction support, performance optimization, and backup strategies Troubleshooting guide for common connection and authentication issues +443/-0  QUEUE_IMPLEMENTATION_SUMMARY.md BullMQ Redis queue implementation with worker and monitoring QUEUE_IMPLEMENTATION_SUMMARY.md BullMQ + Redis queue implementation summary (352 lines) Queue structure with character (priority 1) and page (priority 10) queues Worker startup instructions for development and production Job data structures, retry logic (3 attempts with exponential backoff), and concurrency configuration Admin API endpoints for queue monitoring and management Testing instructions, fallback behavior, and production deployment checklist +352/-0
Configuration	1 files observability-alerts.yml Alert rules configuration for monitoring and incident response observability-alerts.yml Alert rules configuration (286 lines) compatible with Prometheus, Grafana, and Sentry Critical alerts: service down, high error rate, database connection failures Performance alerts: slow page generation, slow planning, high API latency Cost alerts: high AI costs, usage spikes Business alerts: low success rate, no recent generations Resource and AI provider-specific alerts with notification channel routing +286/-0
Additional files	18 files .env.observability.example +117/-0  CRITICAL_ISSUES_SUMMARY.md +206/-0  EXPORT_QUICK_REFERENCE.md +125/-0  IMPLEMENTATION_SUMMARY.md +106/-0  OBSERVABILITY_FILES_INDEX.md +179/-0  OBSERVABILITY_QUICK_START.md +161/-0  QUEUE_FILES_SUMMARY.txt +169/-0  README.md +38/-2    .env.example +13/-0    .env.queue.example +27/-0    PRISMA_QUICK_REFERENCE.md +131/-0  observability-dashboard.json +146/-0  package.json +29/-2    migration.sql +74/-0    README.md +237/-0  test-seed.example.json +31/-0    package.json +11/-0    [id].tsx +177/-4

---

Summary by CodeRabbit

• New Features

  • Episode export: download episodes as PDF or CBZ, with optional audio inclusion from the UI.
  • Background workers: queued background generation for pages and characters with admin controls.
  • Optional PostgreSQL persistence for episodes, pages, and characters.

• Observability

  • Built-in observability: configurable error tracking, distributed tracing, structured logs, dashboards, and alerts.

• Docs

  • Extensive new architecture, accessibility, canvas, and observability guides added.

[coderabbitai]

Walkthrough

This PR introduces comprehensive observability infrastructure (Sentry, OpenTelemetry, structured logging with trace correlation), a Redis-backed BullMQ queue system for background job processing with admin APIs, PostgreSQL persistence via Prisma ORM with schema and migrations, a hardened planner service with input validation and retry logic, episode export functionality supporting PDF and CBZ formats, and extensive documentation updates including new developer guides and implementation reports.

Changes

Cohort / File(s)	Summary
Observability config & dashboards \.env.observability.example, backend/observability-dashboard.json, observability-alerts.yml	Adds example env for observability flags/DSNs/OTLP, a Grafana-style dashboard JSON, and alerting rules for errors, latency, costs and service health.
Backend instrumentation bootstrap backend/src/instrumentation.ts, backend/src/main.ts	Initializes Sentry and OpenTelemetry conditionally, exports sdk, and loads instrumentation early; extends CORS headers for correlation IDs.
Backend observability services backend/src/observability/* (logger.service.ts, tracing.service.ts, correlation.interceptor.ts, instrumentation-helpers.ts, observability.module.ts, test-observability.ts)	New logging/tracing module: Pino-based LoggerService, TracingService with span helpers/Sentry capture, HTTP CorrelationInterceptor, cost/perf helpers, module wiring and test utility.
Frontend observability lib/observability/api-wrapper.ts, sentry.client.config.ts, sentry.server.config.ts, sentry.edge.config.ts, pages/api/observability-test.ts	Adds Next.js API wrapper for observability, Sentry configs for client/server/edge, and a test endpoint.
Queue system & config backend/src/queue/*, backend/.env.queue.example, backend/package.json	Introduces BullMQ-based dual queues (page/character), queue service methods (enqueue, stats, pause/resume, clean, getJob, cancel), queue module/controller, and env template.
Queue admin & events bridge backend/src/queue/queue.controller.ts, backend/src/queue/queue-events-bridge.service.ts	Admin API for queue management and a Redis pub/sub bridge that forwards worker events to SSE EventsService.
Worker process backend/src/worker/generate.worker.ts	Standalone worker implementation for page/character generation with provider selection, storage uploads, Redis event publishing, DB updates, and graceful shutdown.
Database: Prisma schema, migration & seed backend/prisma/schema.prisma, backend/prisma/migrations/.../migration.sql, backend/prisma/migration_lock.toml, backend/prisma/seed.ts, backend/prisma/test-db.ts	Adds Episode/Page/Character models (PageStatus enum), indexes, migration SQL, migration lock, seed script and DB test script.
Prisma error handling util backend/src/prisma/prisma-error-handler.ts	Adds withPrismaErrorHandling, withPrismaTransaction and PrismaError mapping/fallback logic.
Planner overhaul backend/src/planner/* (planner.service.ts, planner.service.hardened.ts, planner.utils.ts, planner.fallback.ts, schemas.ts, test-seed.example.json)	Adds Zod schemas, retry/backoff utils, JSON extraction/repair, metrics, robust PlannerService variants with validation, multi-provider calls, JSON extraction, partial merge/stub fallback and error classes.
Episodes: queue & export integration backend/src/episodes/episodes.service.ts, backend/src/episodes/episodes.controller.ts, backend/src/episodes/episodes.module.ts	EpisodesService now depends on QueueService and supports enqueue/in-process fallback; EpisodesController gains /episodes/:id/export endpoint wired to ExportService; module imports updated.
Export feature backend/src/export/export.module.ts, backend/src/export/export.service.ts	New ExportModule and ExportService supporting PDF and CBZ exports (images, optional audio), temp file handling, and metadata.
App wiring & deps backend/src/app.module.ts, backend/package.json, package.json	AppModule imports ExportModule and ObservabilityModule; package.json additions for OpenTelemetry, Sentry, Pino, Redis, Prisma, PDF/zip tools and related scripts.
Planner env & queue env examples backend/.env.example, backend/.env.queue.example	Adds planner hardening flags (retries/backoff/fallback/partial merge) and queue/Redis config examples.
Frontend export UI pages/episodes/[id].tsx	Adds export modal (PDF/CBZ, include audio), export flow and client-side download handling.
Queue summaries & docs QUEUE_FILES_SUMMARY.txt, OBSERVABILITY_IMPLEMENTATION_REPORT.txt, ARCHITECTURE_VISUAL_SUMMARY.txt	Adds generated reports/documentation describing queue, observability, and architecture verification.
Documentation additions & removals README.md, agent.md, many CANVAS_*, ACCESSIBILITY_*, COLLABORATION_*, BENCHMARK_ANALYSIS.md, etc.; removals: DOCUMENTATION.md, implementation_status.md, warp.md, public/words.md	Large addition of design, research, and implementation docs (canvas, accessibility, collaboration, benchmark, agent guide), and deletion of older docs.
Observability dashboard & alerts backend/observability-dashboard.json, observability-alerts.yml	Dashboard panels, saved searches and alerting rules (added above) as static configs.

Sequence Diagram(s)

sequenceDiagram
    participant User
    participant Frontend
    participant API as NestJS API
    participant Queue as BullMQ Queue
    participant Worker as Background Worker
    participant Redis
    participant DB as PostgreSQL
    participant Storage

    User->>Frontend: Trigger Page Generation
    Frontend->>API: POST /episodes/:id/generate
    API->>Queue: enqueueGeneratePage(jobData)
    Queue->>Redis: Store Job
    Worker->>Redis: Poll for Jobs
    Worker->>Worker: Process Page Generation
    Worker->>Storage: Upload Generated Image
    Worker->>Redis: Publish Progress Event
    Redis->>API: Forward via EventsBridge
    API->>Frontend: SSE: page_progress
    Worker->>DB: Update Page Record
    Worker->>Redis: Publish Completion Event
    Redis->>API: Forward via EventsBridge
    API->>Frontend: SSE: page_done
    Frontend->>User: Display Generated Page

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sequenceDiagram
    participant App as NestJS App
    participant Instrumentation
    participant Sentry
    participant OTEL as OpenTelemetry
    participant Exporter as OTLP Exporter
    participant Request

    App->>Instrumentation: Load instrumentation.ts
    Instrumentation->>Sentry: Initialize (if enabled)
    Sentry-->>Instrumentation: Ready
    Instrumentation->>OTEL: Initialize NodeSDK
    OTEL->>Exporter: Configure OTLP Endpoint
    OTEL-->>Instrumentation: Ready
    Request->>App: HTTP Request
    App->>CorrelationInterceptor: Extract/Generate Correlation ID
    CorrelationInterceptor->>CorrelationInterceptor: Add to Request & Response Headers
    App->>TracingService: Create Span
    TracingService->>OTEL: Record Span with Attributes
    OTEL->>Exporter: Export Trace
    App->>LoggerService: Log Structured Event
    LoggerService->>LoggerService: Inject Trace Context
    LoggerService-->>App: Logged with Correlation ID
    App-->>Request: Response with X-Correlation-ID Header

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sequenceDiagram
    participant User
    participant Frontend
    participant API as Episodes Controller
    participant ExportService
    participant Storage
    participant FileSystem

    User->>Frontend: Click "Export Episode"
    Frontend->>Frontend: Open Export Modal
    User->>Frontend: Select Format & Options
    Frontend->>API: POST /episodes/:id/export?format=pdf&includeAudio=true
    API->>ExportService: export(options)
    ExportService->>Storage: Download Page Images
    Storage-->>ExportService: Image Buffers
    alt Format = PDF
        ExportService->>ExportService: Build PDF with Metadata
    else Format = CBZ
        ExportService->>FileSystem: Create Temp Directory
        ExportService->>ExportService: Create ComicInfo.xml
        ExportService->>FileSystem: Add Images & Audio (optional)
        ExportService->>ExportService: Create ZIP Archive
    end
    ExportService->>FileSystem: Cleanup Temp Files
    ExportService-->>API: ExportResult (buffer, filename, mimeType)
    API-->>Frontend: Stream File with Content-Disposition
    Frontend->>Frontend: Download & Cleanup
    Frontend-->>User: Export Complete

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Estimated code review effort

🎯 4 (Complex) | ⏱️ ~75 minutes

Areas to focus review on:

• Queue integration, multi-queue semantics, job IDs, and Redis pub/sub event correlation.
• Planner service retry/json-extraction/fallback logic and Zod schema coverage.
• Observability bootstrap (early import), OTEL SDK lifecycle, and Sentry beforeSend filters.
• ExportService I/O (downloads, temp files, concurrent exports) and streaming response behavior.
• EpisodesService transaction boundaries and in-process fallback correctness.
• Migration SQL, Prisma schema changes, indexes and seed script safety.
• Worker shutdown handling, provider selection and error recovery.

Possibly related PRs

• Code Review and Debugging Session #2 — overlaps planner service refactor and provider/renderer selection logic; likely touches same planner files and behaviors.

Poem

🐰
I hopped through queues and traced each span,
stitched PDFs with tiny paws and can,
when Redis hummed and Prisma rows did grow,
I thumped my feet — observability aglow,
now manga pages leap where rabbits plan.

Pre-merge checks and finishing touches

❌ Failed checks (1 warning, 1 inconclusive)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 63.64% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.
Title check	❓ Inconclusive	The title 'Add features and run agent' is vague and generic, using non-descriptive terms that fail to convey meaningful information about the changeset.	Revise the title to be more specific and descriptive. Consider: 'Implement observability, queue system, planner hardening, and export functionality' or 'Add BullMQ queues, observability stack, planner validation, and PDF/CBZ export'.

✅ Passed checks (1 passed)

Check name	Status	Explanation
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[qodo-code-review]

PR Compliance Guide 🔍

(Compliance updated until commit f5f209f)

Below is a summary of compliance checks for this PR:

Security Compliance
⚪	Insecure storage exposure Description: The worker uploads images to Supabase using a service role or anon key supplied via environment variables and returns a public URL without enforcing access controls or signed URLs, which could expose generated assets publicly if a service role key is misused or the bucket is public. generate.worker.ts [68-106] Referred Code constructor() { const url = process.env.SUPABASE_URL; const key = process.env.SUPABASE_SERVICE_ROLE_KEY || process.env.SUPABASE_ANON_KEY; this.bucket = process.env.SUPABASE_BUCKET || 'manga-images'; if (url && key) { this.supabase = createClient(url, key, { auth: { autoRefreshToken: false, persistSession: false, }, }); } } get enabled(): boolean { return this.supabase !== null; } async uploadImage(buffer: Buffer, filename: string, contentType = 'image/png'): Promise<string> { if (!this.supabase) { ... (clipped 18 lines)
	Unvalidated binary upload Description: Gemini image generation parsing assumes inline base64 parts and writes images directly to storage without validating MIME type or size, enabling potential memory exhaustion or unsafe file content upload if the API returns unexpected data. generate.worker.ts [151-174] Referred Code const model = this.geminiClient.getGenerativeModel({ model: this.geminiModel, }); const result = await model.generateContent([prompt]); const response = result.response; if (!response.candidates?.[0]?.content?.parts) { throw new Error('No image generated by Gemini'); } // Gemini returns base64 image in parts const imagePart = response.candidates[0].content.parts.find((p: any) => p.inlineData?.mimeType?.startsWith('image/')); if (!imagePart?.inlineData?.data) { throw new Error('No image data in Gemini response'); } const imageBuffer = Buffer.from(imagePart.inlineData.data, 'base64'); const padded = String(pageNumber).padStart(2, '0'); const filename = `episodes/${episodeTitle.replace(/[^a-zA-Z0-9]/g, '_')}/page_${padded}_${seed}.png`; const imageUrl = await storage.uploadImage(imageBuffer, filename, 'image/png'); ... (clipped 3 lines)
	Unbounded remote fetch Description: OpenAI image handling fetches remote URLs and converts them to buffers without size limits or content-type checks, risking SSRF and large file downloads that can exhaust memory or allow unexpected content to be stored. generate.worker.ts [181-214] Referred Code ): Promise<{ imageUrl: string; seed: number }> { console.log(`[renderer] Generating with OpenAI ${this.openaiModel}`); const response = await this.openaiClient.images.generate({ model: this.openaiModel, prompt: prompt.slice(0, 32000), n: 1, size: '1024x1792', quality: 'hd', style: 'natural', response_format: 'b64_json', }); const imageData = response.data?.[0]; if (!imageData?.b64_json && !imageData?.url) { throw new Error('No image data returned from OpenAI'); } let imageBuffer: Buffer; if (imageData.b64_json) { imageBuffer = Buffer.from(imageData.b64_json, 'base64'); ... (clipped 13 lines)
	SSRF via URL download Description: The export service downloads arbitrary image/audio URLs and processes them server-side without domain allowlisting, size limits, or protocol checks, introducing SSRF and denial-of-service risks. export.service.ts [31-59] Referred Code @Injectable() export class ExportService { private async downloadImage(url: string): Promise<Buffer> { try { const response = await axios.get(url, { responseType: 'arraybuffer', timeout: 30000, // 30 second timeout }); return Buffer.from(response.data); } catch (error) { console.error('Failed to download image:', url, error); const errorMessage = error instanceof Error ? error.message : 'Unknown error'; throw new Error(`Failed to download image: ${errorMessage}`); } } private async downloadAudio(url: string): Promise<Buffer> { try { const response = await axios.get(url, { responseType: 'arraybuffer', timeout: 30000, ... (clipped 8 lines)
	Resource exhaustion risk Description: PDF generation embeds user-supplied images without validating file type or limiting dimensions/bytes, which can cause excessive memory usage or malformed file processing leading to resource exhaustion. export.service.ts [69-165] Referred Code const { episodeTitle, pages } = options; // Create a new PDF document const pdfDoc = await PDFDocument.create(); // Set metadata pdfDoc.setTitle(episodeTitle); pdfDoc.setAuthor('MangaFusion'); pdfDoc.setSubject('AI-Generated Manga Episode'); pdfDoc.setKeywords(['manga', 'ai-generated', 'comic']); pdfDoc.setProducer('MangaFusion Platform'); pdfDoc.setCreator('MangaFusion'); pdfDoc.setCreationDate(new Date()); pdfDoc.setModificationDate(new Date()); // Download all images in parallel for better performance const imageDownloadPromises = pages .filter((page) => page.imageUrl) .map(async (page) => { try { const imageBytes = await this.downloadImage(page.imageUrl!); ... (clipped 76 lines)
	Sensitive data in logs Description: Detailed logging of planner failures (including error stacks and seed content) may leak sensitive seed data or operational details to logs, which can be exposed via log aggregation. planner.service.ts [85-123] Referred Code * Main entry point for outline generation with full hardening */ async generateOutline(seed: EpisodeSeed): Promise<PlannerOutput> { const startTime = Date.now(); this.logger.log('Starting Planner Request', { provider: this.provider, seedTitle: seed.title, }); try { // Step 1: Validate input this.validateInput(seed); // Step 2: Generate outline with retries const output = await this.generateOutlineWithRetry(seed); // Step 3: Log success const duration = Date.now() - startTime; this.logger.log('Planner Success', { duration }); return output; ... (clipped 18 lines)
	Information leakage in logs Description: Worker event handlers log error messages directly, which may include upstream API responses or internal details; without sanitization this can leak sensitive information into logs. generate.worker.ts [491-500] Referred Code // ==================== Event Handlers ==================== pageWorker.on('ready', () => console.log('[worker:page] Ready to process jobs')); pageWorker.on('failed', (job, err) => console.error('[worker:page] Job failed:', job?.id, err.message)); pageWorker.on('completed', (job) => console.log('[worker:page] Job completed:', job.id)); characterWorker.on('ready', () => console.log('[worker:character] Ready to process jobs')); characterWorker.on('failed', (job, err) => console.error('[worker:character] Job failed:', job?.id, err.message)); characterWorker.on('completed', (job) => console.log('[worker:character] Job completed:', job.id));
Ticket Compliance
⚪	🎫 No ticket provided Create ticket/issue
Codebase Duplication Compliance
⚪	Codebase context is not defined Follow the guide to enable codebase context checks.
Custom Compliance
🟢	Generic: Meaningful Naming and Self-Documenting Code Objective: Ensure all identifiers clearly express their purpose and intent, making code self-documenting Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
⚪	Generic: Comprehensive Audit Trails Objective: To create a detailed and reliable record of critical system actions for security analysis and compliance. Status: Missing Audit Logs: New critical actions (page/character generation start/progress/completion/failure and DB updates) emit events and console logs but do not create structured audit records tied to a user ID and action outcome. Referred Code console.log(`[worker:page] Processing page ${pageNumber} for episode ${episodeId}`); try { // Emit progress start await emitEvent({ type: 'page_progress', episodeId, page: pageNumber, pct: 5, }); // Update page status to in_progress if (prisma) { await prisma.page.update({ where: { id: pageId }, data: { status: 'in_progress' }, }); } // Get episode and outline from database if (!prisma) { ... (clipped 114 lines) Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Robust Error Handling and Edge Case Management Objective: Ensure comprehensive error handling that provides meaningful context and graceful degradation Status: Unhandled Fallbacks: Refinement providers 'replicate' and 'gemini' throw unimplemented errors without graceful fallback or retry, and external input (URLs/params) lack validation and sanitization. Referred Code /** * Refine using Replicate ControlNet */ private async refineWithReplicate( request: RefinementRequest ): Promise<string> { this.logger.log('Using Replicate ControlNet for refinement'); // Placeholder - implement Replicate API integration throw new Error('Replicate integration not yet implemented'); } /** * Refine using Gemini image generation */ private async refineWithGemini( request: RefinementRequest ): Promise<string> { this.logger.log('Using Gemini for refinement'); // Placeholder - implement Gemini API integration ... (clipped 2 lines) Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Error Handling Objective: To prevent the leakage of sensitive system information through error messages while providing sufficient detail for internal debugging. Status: Error Detail Exposure: Errors caught in worker are emitted via Redis events with raw error messages which may expose internal details to clients consuming these events. Referred Code // Emit failure event await emitEvent({ type: 'page_failed', episodeId, page: pageNumber, error: error.message || String(error), }); Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Logging Practices Objective: To ensure logs are useful for debugging and auditing without exposing sensitive information like PII, PHI, or cardholder data. Status: Verbose Console Logs: The hardened planner service uses console logging of errors and request context which may include sensitive provider or seed details without redaction or structured logging controls. Referred Code async generateOutline(seed: EpisodeSeed): Promise<PlannerOutput> { const startTime = Date.now(); console.log('=== Starting Planner Request ==='); console.log('Provider:', this.provider); console.log('Seed title:', seed.title); try { // Step 1: Validate input this.validateInput(seed); // Step 2: Generate outline with retries const output = await this.generateOutlineWithRetry(seed); // Step 3: Log success const duration = Date.now() - startTime; console.log(`=== Planner Success (${duration}ms) ===`); return output; } catch (error) { const duration = Date.now() - startTime; console.error(`=== Planner Failed (${duration}ms) ===`); ... (clipped 19 lines) Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Security-First Input Validation and Data Handling Objective: Ensure all data inputs are validated, sanitized, and handled securely to prevent vulnerabilities Status: Missing Validation: The refinement endpoints accept external URLs and parameters (e.g., sketchImageUrl, controlnetType) without validation/sanitization or content-type checks before forwarding to third-party APIs and storage. Referred Code interface RefinementRequest { pageId: string; canvasId: string; sketchImageUrl: string; style?: string; strength?: number; controlnetType?: 'scribble' | 'canny' | 'depth' | 'hed'; promptDescription?: string; aiProvider?: 'segmind' | 'replicate' | 'gemini'; } @Injectable() export class RefinementService { private readonly logger = new Logger(RefinementService.name); private supabase: any; Learn more about managing compliance generic rules or creating your own custom rules

Compliance status legend

🟢 - Fully Compliant
🟡 - Partial Compliant
🔴 - Not Compliant
⚪ - Requires Further Human Verification
🏷️ - Compliance label

---

Previous compliance checks

Compliance check up to commit 9dcaf71

Security Compliance
⚪	Insecure storage usage Description: Supabase storage is instantiated with a service role or anon key read directly from environment and used server-side to upload unvalidated, arbitrarily named files without path validation, which risks key leakage misuse and path traversal-like bucket pollution if filenames include crafted segments (e.g., '../../') or overlong values. generate.worker.ts [64-105] Referred Code class WorkerStorageService { private supabase: any = null; private readonly bucket: string; constructor() { const url = process.env.SUPABASE_URL; const key = process.env.SUPABASE_SERVICE_ROLE_KEY || process.env.SUPABASE_ANON_KEY; this.bucket = process.env.SUPABASE_BUCKET || 'manga-images'; if (url && key) { this.supabase = createClient(url, key, { auth: { autoRefreshToken: false, persistSession: false, }, }); } } get enabled(): boolean { return this.supabase !== null; ... (clipped 21 lines)
	Unvalidated filename construction Description: The worker builds storage filenames from episode titles without length or character whitelisting beyond a basic regex and uploads images directly from AI responses, enabling path/identifier manipulation and uncontrolled file write within the bucket if episode titles are attacker-controlled. generate.worker.ts [146-170] Referred Code const model = this.geminiClient.getGenerativeModel({ model: this.geminiModel, }); const result = await model.generateContent([prompt]); const response = result.response; if (!response.candidates?.[0]?.content?.parts) { throw new Error('No image generated by Gemini'); } // Gemini returns base64 image in parts const imagePart = response.candidates[0].content.parts.find((p: any) => p.inlineData?.mimeType?.startsWith('image/')); if (!imagePart?.inlineData?.data) { throw new Error('No image data in Gemini response'); } const imageBuffer = Buffer.from(imagePart.inlineData.data, 'base64'); const padded = String(pageNumber).padStart(2, '0'); const filename = `episodes/${episodeTitle.replace(/[^a-zA-Z0-9]/g, '_')}/page_${padded}_${seed}.png`; ... (clipped 4 lines)
	Unsanitized external fetch Description: OpenAI image URLs (when provided) are fetched and blindly written to storage without validation or size/type limits, which may allow SSRF or large file ingestion causing resource exhaustion if an attacker influences the URL. generate.worker.ts [176-210] Referred Code pageNumber: number, ): Promise<{ imageUrl: string; seed: number }> { console.log(`[renderer] Generating with OpenAI ${this.openaiModel}`); const response = await this.openaiClient.images.generate({ model: this.openaiModel, prompt: prompt.slice(0, 32000), n: 1, size: '1024x1792', quality: 'hd', style: 'natural', response_format: 'b64_json', }); const imageData = response.data?.[0]; if (!imageData?.b64_json && !imageData?.url) { throw new Error('No image data returned from OpenAI'); } let imageBuffer: Buffer; if (imageData.b64_json) { ... (clipped 14 lines)
	SSRF via arbitrary URL Description: Export service downloads images and audio from arbitrary URLs provided in page data without allowlisting, authentication, or size limits besides a 30s timeout, exposing the server to SSRF and potentially large downloads leading to DoS. export.service.ts [34-58] Referred Code try { const response = await axios.get(url, { responseType: 'arraybuffer', timeout: 30000, // 30 second timeout }); return Buffer.from(response.data); } catch (error) { console.error('Failed to download image:', url, error); const errorMessage = error instanceof Error ? error.message : 'Unknown error'; throw new Error(`Failed to download image: ${errorMessage}`); } } private async downloadAudio(url: string): Promise<Buffer> { try { const response = await axios.get(url, { responseType: 'arraybuffer', timeout: 30000, }); return Buffer.from(response.data); } catch (error) { ... (clipped 4 lines)
	Sensitive event leakage Description: Worker publishes JSON-serialized events from job data directly to Redis Pub/Sub without redaction, potentially leaking sensitive episode metadata or user-provided content to subscribers if channels are shared or misconfigured. generate.worker.ts [52-60] Referred Code const eventPublisher = new Redis(REDIS_URL); async function emitEvent(event: EventPayload): Promise<void> { try { await eventPublisher.publish('worker:events', JSON.stringify(event)); } catch (error) { console.error('[worker] Failed to publish event:', error); } }
	Unvalidated data persistence Description: Prisma operations serialize and persist entire seed and outline objects cast as any without field-level validation or redaction, risking storage of sensitive or unexpectedly large user-provided data that could later be exposed via APIs. episodes.service.ts [51-116] Referred Code try { // Use transaction to ensure episode, pages, and characters are created atomically const created = await withPrismaTransaction( this.prisma.client, 'planEpisode', async (tx) => { // Create episode with pages in a single transaction const episode = await tx.episode.create({ data: { id, seedInput: seed as any, outline: outline as any, rendererModel: rendererModel, pages: { create: Array.from({ length: 10 }).map((_, idx) => ({ pageNumber: idx + 1, status: 'queued', version: 0, })), }, }, ... (clipped 45 lines)
	Sensitive logging Description: The API wrapper logs request headers and errors to console and sends them to Sentry, which may include sensitive values (e.g., Authorization, cookies) since there is no explicit header redaction before logging. api-wrapper.ts [91-121] Referred Code // Capture error in Sentry if (process.env.NEXT_PUBLIC_ENABLE_OBSERVABILITY === 'true') { Sentry.captureException(error, { tags: { correlation_id: correlationId, api_route: req.url || 'unknown', }, contexts: { request: { method: req.method, url: req.url, headers: req.headers, }, }, }); } // Log error if (typeof window === 'undefined') { console.error( JSON.stringify({ ... (clipped 10 lines)
	Error log leakage Description: Worker 'failed' event logs include err.message without scrubbing; coupled with upstream errors that might include API keys or prompts, this can expose sensitive data in logs. generate.worker.ts [467-474] Referred Code pageWorker.on('ready', () => console.log('[worker:page] Ready to process jobs')); pageWorker.on('failed', (job, err) => console.error('[worker:page] Job failed:', job?.id, err.message)); pageWorker.on('completed', (job) => console.log('[worker:page] Job completed:', job.id)); characterWorker.on('ready', () => console.log('[worker:character] Ready to process jobs')); characterWorker.on('failed', (job, err) => console.error('[worker:character] Job failed:', job?.id, err.message)); characterWorker.on('completed', (job) => console.log('[worker:character] Job completed:', job.id));
	Excessive diagnostic logging Description: Planner metrics and logs print detailed retry and error information to console, potentially including fragments of AI responses or validation details that may contain sensitive user input without redaction. planner.utils.ts [241-311] Referred Code */ export function formatZodError(error: ZodError): string { const issues = error.issues.map(issue => { const path = issue.path.join('.'); return ` - ${path || 'root'}: ${issue.message}`; }); return `Validation failed:\n${issues.join('\n')}`; } /** * Metrics tracker for planner operations */ export class PlannerMetrics { private successCount = 0; private failureCount = 0; private totalAttempts = 0; private validationErrors = 0; private jsonExtractionErrors = 0; private apiErrors = 0; private retrySuccesses = 0; ... (clipped 50 lines)
	Unvalidated binary write Description: Gemini response parsing trusts inlineData parts and writes decoded base64 directly to storage without verifying content-type or validating the image, allowing malformed/binary payload storage which could be abused if upstream is compromised. generate.worker.ts [116-170] Referred Code private get geminiClient() { if (!this.geminiApiKey) throw new Error('GEMINI_API_KEY not set'); return new GoogleGenerativeAI(this.geminiApiKey); } private get openaiClient() { if (!this.openaiApiKey) throw new Error('OPENAI_API_KEY not set'); return new OpenAI({ apiKey: this.openaiApiKey }); } async generatePageImage( prompt: string, seed: number, episodeTitle: string, pageNumber: number, ): Promise<{ imageUrl: string; seed: number }> { if (this.provider === 'openai') { return this.generateWithOpenAI(prompt, seed, episodeTitle, pageNumber); } else { return this.generateWithGemini(prompt, seed, episodeTitle, pageNumber); } ... (clipped 34 lines)
Ticket Compliance
⚪	🎫 No ticket provided Create ticket/issue
Codebase Duplication Compliance
⚪	Codebase context is not defined Follow the guide to enable codebase context checks.
Custom Compliance
🟢	Generic: Meaningful Naming and Self-Documenting Code Objective: Ensure all identifiers clearly express their purpose and intent, making code self-documenting Status: Passed Learn more about managing compliance generic rules or creating your own custom rules
🔴	Generic: Secure Error Handling Objective: To prevent the leakage of sensitive system information through error messages while providing sufficient detail for internal debugging. Status: Sensitive error logs: The worker logs full error objects and stack traces to console (including external provider errors and DB messages), which could expose internal details if surfaced to users or shared logs. Referred Code } catch (error: any) { console.error(`[worker:page] Failed page ${pageNumber}:`, error); // Update database with error if (prisma) { await prisma.page.update({ where: { id: pageId }, data: { status: 'failed', error: error.message || String(error), }, }); } // Emit failure event await emitEvent({ type: 'page_failed', episodeId, page: pageNumber, error: error.message || String(error), }); ... (clipped 35 lines) Learn more about managing compliance generic rules or creating your own custom rules
⚪	Generic: Comprehensive Audit Trails Objective: To create a detailed and reliable record of critical system actions for security analysis and compliance. Status: Action logging gaps: New code performs critical actions (DB updates, queue job processing, exports) with mostly console logging and without consistently logging user identity or full action context, making audit reconstruction uncertain. Referred Code const { episodeId, pageId, pageNumber, seed, styleRefUrls, editPrompt, baseImageUrl, dialogueTextOverride } = job.data; console.log(`[worker:page] Processing page ${pageNumber} for episode ${episodeId}`); try { // Emit progress start await emitEvent({ type: 'page_progress', episodeId, page: pageNumber, pct: 5, }); // Update page status to in_progress if (prisma) { await prisma.page.update({ where: { id: pageId }, data: { status: 'in_progress' }, }); } ... (clipped 91 lines) Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Robust Error Handling and Edge Case Management Objective: Ensure comprehensive error handling that provides meaningful context and graceful degradation Status: Partial error handling: While many errors are caught and logged, exports and worker paths still use generic console logs and may swallow actionable context or continue without clear reporting, potentially missing edge cases like missing DB/storage configuration. Referred Code const { episodeTitle, pages } = options; // Create a new PDF document const pdfDoc = await PDFDocument.create(); // Set metadata pdfDoc.setTitle(episodeTitle); pdfDoc.setAuthor('MangaFusion'); pdfDoc.setSubject('AI-Generated Manga Episode'); pdfDoc.setKeywords(['manga', 'ai-generated', 'comic']); pdfDoc.setProducer('MangaFusion Platform'); pdfDoc.setCreator('MangaFusion'); pdfDoc.setCreationDate(new Date()); pdfDoc.setModificationDate(new Date()); // Add each page image to the PDF for (const page of pages) { if (!page.imageUrl) { console.warn(`Page ${page.pageNumber} has no image, skipping`); continue; } ... (clipped 56 lines) Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Secure Logging Practices Objective: To ensure logs are useful for debugging and auditing without exposing sensitive information like PII, PHI, or cardholder data. Status: Console logging used: The hardened planner and worker heavily use console logging, potentially unstructured and including dynamic content (provider, titles), and may risk leaking sensitive data depending on seed contents. Referred Code const startTime = Date.now(); console.log('=== Starting Planner Request ==='); console.log('Provider:', this.provider); console.log('Seed title:', seed.title); try { // Step 1: Validate input this.validateInput(seed); // Step 2: Generate outline with retries const output = await this.generateOutlineWithRetry(seed); // Step 3: Log success const duration = Date.now() - startTime; console.log(`=== Planner Success (${duration}ms) ===`); return output; } catch (error) { const duration = Date.now() - startTime; console.error(`=== Planner Failed (${duration}ms) ===`); console.error('Error:', error); ... (clipped 18 lines) Learn more about managing compliance generic rules or creating your own custom rules
	Generic: Security-First Input Validation and Data Handling Objective: Ensure all data inputs are validated, sanitized, and handled securely to prevent vulnerabilities Status: Unsafe filename build: Worker builds storage filenames from episode titles without full sanitization/normalization and downloads external URLs without explicit validation, which may risk path or content handling issues. Referred Code const imageBuffer = Buffer.from(imagePart.inlineData.data, 'base64'); const padded = String(pageNumber).padStart(2, '0'); const filename = `episodes/${episodeTitle.replace(/[^a-zA-Z0-9]/g, '_')}/page_${padded}_${seed}.png`; const imageUrl = await storage.uploadImage(imageBuffer, filename, 'image/png'); return { imageUrl, seed }; } private async generateWithOpenAI( prompt: string, seed: number, episodeTitle: string, pageNumber: number, ): Promise<{ imageUrl: string; seed: number }> { console.log(`[renderer] Generating with OpenAI ${this.openaiModel}`); const response = await this.openaiClient.images.generate({ model: this.openaiModel, prompt: prompt.slice(0, 32000), n: 1, size: '1024x1792', ... (clipped 23 lines) Learn more about managing compliance generic rules or creating your own custom rules

[qodo-code-review]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Impact
High-level	Unify the backend architecture The PR's dual-backend architecture, where Next.js API routes import NestJS services, is causing build failures. The suggestion is to unify the backend by having the Next.js frontend communicate with the NestJS backend exclusively via HTTP API calls. Examples: ARCHITECTURE_VERIFICATION_REPORT.md [21-40] **Status:** 🔴 **CRITICAL BUILD FAILURE** - Frontend build blocked by architectural issue --- ## 🔴 Critical Issues (Build Blockers) ### CRITICAL-001: Frontend Build Failure - NestJS Decorator Incompatibility **Severity:** CRITICAL **Impact:** Cannot build or deploy the application ... (clipped 10 lines) ARCHITECTURE_VERIFICATION_REPORT.md [69-90] **Severity:** HIGH **Impact:** Architectural inconsistency, maintenance burden **Problem:** The system runs TWO separate server implementations: 1. **NestJS Backend** (Port 4000) - Path: `/home/user/mangafusion/backend/src/` - Features: Full DI, all 5 new features, proper module structure ... (clipped 12 lines) Solution Walkthrough: Before: // In a hypothetical Next.js API route, as described in the report // This pattern causes a build failure due to NestJS decorators. // Direct import from backend source code import { EpisodesService } from '../../backend/src/episodes/episodes.service'; import { PlannerService } from '../../backend/src/planner/planner.service'; // ... other services // Manual dependency injection, creating a second instance of services const planner = new PlannerService(...); // This container is missing the QueueService, leading to inconsistent behavior. const episodesService = new EpisodesService(..., planner, ...); export default async function handler(req, res) { // Directly calling service methods, bypassing the NestJS server const result = await episodesService.planEpisode(req.body); res.status(200).json(result); } After: // In a Next.js API route, acting as a proxy to the NestJS backend export default async function handler(req, res) { // The Next.js API route now acts as a simple proxy. // It calls the single, unified NestJS backend via HTTP. const nestJsBackendUrl = 'http://localhost:4000/api/episodes'; try { const response = await fetch(nestJsBackendUrl, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify(req.body), }); const data = await response.json(); res.status(response.status).json(data); } catch (error) { res.status(500).json({ message: 'Internal Server Error' }); } } Suggestion importance[1-10]: 10 __ Why: The suggestion correctly identifies a critical architectural flaw, confirmed by the PR's own ARCHITECTURE_VERIFICATION_REPORT.md, which causes a build failure and makes the system un-deployable.	High
Possible issue	✅ Use a singleton Redis client Suggestion Impact: The commit implemented a singleton Redis publisher with getPublisher, added error handling, replaced per-call creation in emitWorkerEvent, and added a closePublisher method. code diff: + * Singleton Redis publisher for worker events (prevents connection overhead) + */ + private static publisher: Redis | null = null; + + private static getPublisher(redisUrl: string): Redis { + if (!this.publisher) { + this.publisher = new Redis(redisUrl, { + maxRetriesPerRequest: null, + enableReadyCheck: false, + }); + + // Handle connection errors + this.publisher.on('error', (err) => { + console.error('Redis publisher error:', err); + // Reset publisher on critical errors + if (this.publisher?.status === 'end') { + this.publisher = null; + } + }); + } + return this.publisher; + } + + /** + * Gracefully close the singleton publisher + */ + static async closePublisher(): Promise<void> { + if (this.publisher) { + await this.publisher.quit(); + this.publisher = null; + } + } + + /** * Helper for workers to publish events to this bridge. * Workers should call this via a Redis publisher. */ static async emitWorkerEvent(redisUrl: string, event: EventPayload): Promise<void> { - const publisher = new Redis(redisUrl); - try { - await publisher.publish('worker:events', JSON.stringify(event)); - } finally { - await publisher.quit(); - } + const publisher = this.getPublisher(redisUrl); + await publisher.publish('worker:events', JSON.stringify(event)); } To improve performance and reduce resource usage, replace the per-call Redis connection with a shared, singleton Redis client for publishing events. backend/src/queue/queue-events-bridge.service.ts [109-116] +private static publisher: Redis | null = null; + +private static getPublisher(redisUrl: string): Redis { + if (!this.publisher) { + this.publisher = new Redis(redisUrl, { + maxRetriesPerRequest: null, + enableReadyCheck: false, + }); + // It's good practice to handle connection errors + this.publisher.on('error', (err) => { + console.error('Redis publisher error:', err); + // On critical errors, you might want to reset the publisher + if (this.publisher?.status === 'end') { + this.publisher = null; + } + }); + } + return this.publisher; +} + static async emitWorkerEvent(redisUrl: string, event: EventPayload): Promise<void> { - const publisher = new Redis(redisUrl); - try { - await publisher.publish('worker:events', JSON.stringify(event)); - } finally { - await publisher.quit(); + const publisher = this.getPublisher(redisUrl); + await publisher.publish('worker:events', JSON.stringify(event)); +} + +// Consider adding a static method to gracefully close the publisher on worker shutdown. +static async closePublisher(): Promise<void> { + if (this.publisher) { + await this.publisher.quit(); + this.publisher = null; } } [To ensure code accuracy, apply this suggestion manually] Suggestion importance[1-10]: 8 __ Why: This suggestion correctly identifies a critical performance anti-pattern and provides a robust solution using a singleton pattern, which will prevent resource exhaustion and significantly improve performance under load.	Medium
	✅ Add null check for public URL Suggestion Impact: The commit added the suggested null checks: it throws an error if the upload returns no data and if the public URL is missing, aligning with the recommendation. code diff: if (error) throw new Error(`Storage upload failed: ${error.message}`); + if (!data) throw new Error('Storage upload returned no data.'); const { data: publicData } = this.supabase.storage.from(this.bucket).getPublicUrl(data.path); + if (!publicData?.publicUrl) { + throw new Error('Failed to get public URL for uploaded image.'); + } return publicData.publicUrl; Add null checks after Supabase storage upload and getPublicUrl calls to prevent potential runtime errors from null data. backend/src/worker/generate.worker.ts [94-101] const { data, error } = await this.supabase.storage .from(this.bucket) .upload(filename, buffer, { contentType, upsert: true }); if (error) throw new Error(`Storage upload failed: ${error.message}`); +if (!data) throw new Error('Storage upload returned no data.'); const { data: publicData } = this.supabase.storage.from(this.bucket).getPublicUrl(data.path); +if (!publicData?.publicUrl) { + throw new Error('Failed to get public URL for uploaded image.'); +} return publicData.publicUrl; [To ensure code accuracy, apply this suggestion manually] Suggestion importance[1-10]: 7 __ Why: The suggestion correctly identifies a potential null reference error that could crash the worker process and adds necessary checks to prevent it.	Medium
	✅ Improve error handling for character jobs Suggestion Impact: The commit enhanced processCharacterJob error handling by emitting character_done and character_failed events and adjusting success comment, partially addressing the suggestion’s intent to improve failure handling. However, it did not add DB status/error updates as proposed. code diff: } catch (error: any) { console.error(`[worker:character] Failed character "${name}":`, error); - throw error; + + // Emit character_failed event for real-time updates + await emitEvent({ + type: 'character_failed', + episodeId, + characterId, + name, + error: error.message || String(error), + } as any); + + throw error; // Re-throw to mark job as failed } Align processCharacterJob error handling with processPageJob by updating the database with a 'failed' status and error message when a job fails. backend/src/worker/generate.worker.ts [418-447] async function processCharacterJob(job: Job<GenerateCharacterJobData>) { const { episodeId, characterId, name, description, assetFilename, visualStyle, episodeTitle } = job.data; console.log(`[worker:character] Processing character "${name}" for episode ${episodeId}`); try { + // Update status to in_progress + if (prisma) { + await (prisma as any).character.update({ + where: { id: characterId }, + data: { status: 'in_progress' }, + }); + } + // Generate character image const result = await renderer.generateCharacterImage( name, description, visualStyle, episodeTitle, assetFilename, ); // Update database if (prisma) { await (prisma as any).character.update({ where: { id: characterId }, - data: { imageUrl: result.imageUrl }, + data: { imageUrl: result.imageUrl, status: 'done', error: null }, }); } + + // TODO: Emit a 'character_done' event if needed for real-time updates. console.log(`[worker:character] Completed character "${name}" for episode ${episodeId}`); return result; } catch (error: any) { console.error(`[worker:character] Failed character "${name}":`, error); + + if (prisma) { + await (prisma as any).character.update({ + where: { id: characterId }, + data: { + status: 'failed', + error: error.message || String(error), + }, + }); + } + + // TODO: Emit a 'character_failed' event if needed for real-time updates. + throw error; } } [To ensure code accuracy, apply this suggestion manually] Suggestion importance[1-10]: 7 __ Why: The suggestion correctly identifies inconsistent error handling between processPageJob and processCharacterJob and proposes a fix that improves application state management on job failure.	Medium
	Prevent NaN in AI cost calculations Refactor the AI cost calculation logic to handle different pricing structures for text (token-based) and image (per-unit) models to prevent incorrect metric reporting. OBSERVABILITY.md [483-492] // In instrumentation-helpers.ts export const AI_COSTS = { openai: { - 'gpt-5-mini': { input: 0.0001, output: 0.0002 }, + 'gpt-5-mini': { input: 0.0001, output: 0.0002 }, // Per 1k tokens 'gpt-image-1': { per_image: 0.04 }, }, gemini: { - 'gemini-2.5-flash': { input: 0.00001, output: 0.00003 }, + 'gemini-2.5-flash': { input: 0.00001, output: 0.00003 }, // Per 1k tokens }, }; +// In a function like calculateAICost +const modelInfo = AI_COSTS[provider]?.[model]; +if (!modelInfo) return 0; + +let cost = 0; +if ('input' in modelInfo && 'output' in modelInfo) { + cost = ((promptTokens / 1000) * modelInfo.input) + ((completionTokens / 1000) * modelInfo.output); +} else if ('per_image' in modelInfo) { + // Assuming 1 image per call, or pass image count to function + cost = modelInfo.per_image; +} +return cost; + Apply / Chat Suggestion importance[1-10]: 7 __ Why: The suggestion correctly identifies a potential bug where the cost calculation logic might not handle different pricing structures for text and image models, leading to incorrect cost metrics.	Medium
General	Parallelize downloads to speed up exports Improve export performance and reliability by parallelizing image and audio file downloads using Promise.all. EXPORT_FEATURE.md [33-42] -#### 1. Export Service (`/backend/src/export/export.service.ts`) +// In export.service.ts, within a method like exportAsCBZ -The core service that handles file generation: +// ... +const imageDownloadPromises = pages.map(page => + this.downloadImage(page.imageUrl).then(buffer => ({ + name: `page_${String(page.pageNumber).padStart(3, '0')}.png`, + data: buffer, + })) +); -**Key Methods:** -- `exportAsPDF(options)`: Generates PDF files using pdf-lib -- `exportAsCBZ(options)`: Creates CBZ archives using archiver -- `downloadImage(url)`: Downloads images from Supabase storage -- `downloadAudio(url)`: Downloads audio files from storage -- `generateComicInfoXml()`: Creates metadata for CBZ files +const audioDownloadPromises = includeAudio + ? pages + .filter(p => p.audioUrl) + .map(page => + this.downloadAudio(page.audioUrl).then(buffer => ({ + name: `audio/page_${String(page.pageNumber).padStart(3, '0')}.mp3`, + data: buffer, + })) + ) + : []; +const [imageAssets, audioAssets] = await Promise.all([ + Promise.all(imageDownloadPromises), + Promise.all(audioDownloadPromises), +]); + +imageAssets.forEach(asset => archive.append(asset.data, { name: asset.name })); +audioAssets.forEach(asset => archive.append(asset.data, { name: asset.name })); +// ... + [To ensure code accuracy, apply this suggestion manually] Suggestion importance[1-10]: 8 __ Why: This is a high-impact performance optimization that directly addresses the long generation times and timeout risks mentioned in the documentation by suggesting parallel downloads.	Medium
Update

[coderabbitai]

Actionable comments posted: 19

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (2)

backend/src/episodes/episodes.service.ts (2)

369-406: Guard queue-based page generation on Prisma to avoid misconfigured deployments

Right now startGeneration uses the queue whenever this.queue.enabled is true, even if Prisma is disabled. Since queued workers rely on DB state, enabling Redis without a database would enqueue jobs that can’t be processed, while this service assumes work is happening.

To make this more robust, gate queue usage on both Redis and Prisma being enabled, and fall back to in‑process generation otherwise:

-    // Use queue if enabled, otherwise fall back to in-process generation
-    if (this.queue.enabled) {
-      this.logger.log(`Using background queue for episode ${episodeId} page generation`);
+    // Use queue only when both Redis and Prisma are enabled; otherwise fall back to in-process generation
+    if (this.queue.enabled && this.prisma.enabled) {
+      this.logger.log(`Using background queue for episode ${episodeId} page generation`);
@@
-    } else {
-      this.logger.log(`Using in-process generation for episode ${episodeId} (queue disabled)`);
+    } else {
+      this.logger.log(`Using in-process generation for episode ${episodeId} (queue or Prisma disabled)`);

This avoids “successfully” enqueuing work that cannot complete in configurations without a DB.

---

572-679: Apply the same Prisma+queue guard to character generation

generateCharacters also branches on this.queue.enabled, but then assumes Prisma is enabled to look up or create character rows before enqueueing jobs. If Redis is configured but Prisma is not, the current code falls into the queue branch yet immediately continues for each character (due to if (this.prisma.enabled) { ... } else { continue; }), effectively doing nothing.

It would be clearer and safer to align the condition with startGeneration and only use the queue when Prisma is enabled:

-    // Use queue if enabled, otherwise fall back to in-process generation
-    if (this.queue.enabled) {
+    // Use queue only when both Redis and Prisma are enabled; otherwise fall back to in-process generation
+    if (this.queue.enabled && this.prisma.enabled) {

This ensures that in deployments with Redis but no DB, characters are still generated via the in‑process path.

🧹 Nitpick comments (58)

.env.observability.example (1)

64-83: Consider centralizing planner configuration.

The planner configuration here duplicates values from backend/.env.example (lines 33-40). This duplication could lead to inconsistencies if these values are updated in only one location.

Consider one of these approaches:

1. Reference backend/.env.example in a comment and remove the duplication
2. Add a note indicating these values should match backend/.env.example
3. Document that this file is meant to be a comprehensive reference that includes all relevant config

Apply this diff to add a clarifying comment:

 # ===========================================
 # PLANNER SERVICE CONFIGURATION (for observability)
 # ===========================================
+# Note: These values should match backend/.env.example planner settings
 
 # Enable stub fallback if planner fails (default: true)
 PLANNER_ENABLE_STUB_FALLBACK=true

backend/src/instrumentation.ts (3)

50-56: Harden OTLP headers parsing to avoid startup crashes

OTEL_EXPORTER_OTLP_HEADERS is parsed with a bare JSON.parse. Any typo in the env value will throw and prevent the backend from starting when observability is enabled.

Consider wrapping this in a small try/catch and falling back to {} with a warning:

-  const traceExporter = new OTLPTraceExporter({
-    url: process.env.OTEL_EXPORTER_OTLP_ENDPOINT || 'http://localhost:4318/v1/traces',
-    headers: process.env.OTEL_EXPORTER_OTLP_HEADERS
-      ? JSON.parse(process.env.OTEL_EXPORTER_OTLP_HEADERS)
-      : {},
-  });
+  let otlpHeaders: Record<string, string> = {};
+  const rawHeaders = process.env.OTEL_EXPORTER_OTLP_HEADERS;
+  if (rawHeaders) {
+    try {
+      otlpHeaders = JSON.parse(rawHeaders);
+    } catch (err) {
+      console.warn('Invalid OTEL_EXPORTER_OTLP_HEADERS JSON, ignoring value:', err);
+    }
+  }
+
+  const traceExporter = new OTLPTraceExporter({
+    url: process.env.OTEL_EXPORTER_OTLP_ENDPOINT || 'http://localhost:4318/v1/traces',
+    headers: otlpHeaders,
+  });

---

28-32: Make health‑endpoint filters consistent between Sentry and OTel

Sentry’s beforeSend uses event.request?.url?.includes('/health'), while the HTTP instrumentation’s ignoreIncomingRequestHook uses strict equality on req.url (=== '/api/health' || '/health').

This means /health?check=1 will be ignored by Sentry but still traced by OTel. If the intent is to fully drop health traffic, consider switching the OTel side to startsWith or a similar prefix check.

Also applies to: 68-73

---

78-88: Check interaction between SIGTERM handler and NestJS shutdown

The SIGTERM handler calls sdk.shutdown() and then process.exit(0) in finally. If Nest is also using enableShutdownHooks / beforeApplicationShutdown, this explicit process.exit can short‑circuit other cleanup logic.

Recommend verifying how this behaves in your deployment (e.g., Ctrl‑C in dev, container stop in prod) and, if needed, moving sdk.shutdown() into Nest’s shutdown path instead of exiting the process here.

backend/src/export/export.module.ts (1)

1-8: Confirm ExportService dependencies are satisfied by module imports

Module wiring is clean and minimal. One thing to double‑check: if ExportService injects things like PrismaService, storage, or observability services, those providers must either:

• Come from modules imported here (e.g., imports: [PrismaModule, StorageModule, ObservabilityModule]), or
• Be provided by a @Global() module.

If any of its dependencies are only imported in AppModule or EpisodesModule, you may hit “Nest can’t resolve dependencies of ExportService” at runtime.

OBSERVABILITY_FILES_INDEX.md (3)

8-76: Optional: Add blank lines around tables for better Markdown compatibility.

Static analysis flagged that tables should be surrounded by blank lines per MD058. While many renderers handle this gracefully, adding blank lines improves compatibility across parsers.

Apply this pattern to all tables:

 ### Core Instrumentation
+
 | File | Lines | Purpose |
 |------|-------|---------|
 | `/backend/src/instrumentation.ts` | 92 | OpenTelemetry + Sentry initialization (loaded first) |
+
 ### Observability Module

---

81-115: Specify language for fenced code blocks.

The file structure tree at lines 81-115 is in a fenced code block without a language identifier. Adding text or plaintext improves syntax highlighting and accessibility.

-```
+```text
 mangafusion/
 ├── backend/

---

148-157: Git status section may become stale over time.

The git status instructions reference "17 new files" and "4 modified files" which are specific to this PR. This content will become outdated as the repository evolves.

Consider either:

• Removing the git-specific instructions
• Moving them to the PR description instead
• Adding a note that numbers are specific to the initial implementation

 ## Git Status

-All files are ready to commit:
+All files from the initial observability implementation are ready to commit:
 
 ```bash
 git add .
 git status
-# Should show:
+# Initial implementation shows:
 # - 17 new files
 # - 4 modified files

</blockquote></details>
<details>
<summary>backend/prisma/seed.ts (1)</summary><blockquote>

`80-146`: **Consider using consistent pattern for creating pages.**

Episode 1 pages (lines 80-146) are created with explicit individual objects, while Episode 2 pages (lines 237-244) use `Array.from` with a generator. The latter is more concise and maintainable.



Consider refactoring Episode 1 page creation for consistency:

```diff
-  const pages = await prisma.page.createMany({
-    data: [
-      {
-        episodeId: episode.id,
-        pageNumber: 1,
-        status: 'done',
-        imageUrl: 'https://placehold.co/1024x1536/000/FFF?text=Page+1',
-        seed: 123456,
-        version: 1,
-      },
-      // ... 9 more individual objects
-    ],
-  });
+  const pages = await prisma.page.createMany({
+    data: [
+      {
+        episodeId: episode.id,
+        pageNumber: 1,
+        status: 'done',
+        imageUrl: 'https://placehold.co/1024x1536/000/FFF?text=Page+1',
+        seed: 123456,
+        version: 1,
+      },
+      ...Array.from({ length: 9 }, (_, i) => ({
+        episodeId: episode.id,
+        pageNumber: i + 2,
+        status: 'queued' as const,
+        version: 0,
+      })),
+    ],
+  });

backend/src/planner/README.md (2)

165-174: Specify language for fenced code block.

The error messages example at lines 165-174 would benefit from a language specifier for better rendering.

-```
+```text
 Input validation failed:
   - title: Title is required

---

200-222: Specify language for monitoring log example.

The monitoring logs example would benefit from a language specifier (e.g., text or log).

-```
+```text
 === Starting Planner Request ===

OBSERVABILITY_QUICK_START.md (2)

44-50: Optional: Format bare URLs as Markdown links.

Static analysis flagged bare URLs at lines 44, 48, and 50. While functional, Markdown links provide better semantics.

-- **Traces**: http://localhost:16686 (Jaeger UI)
+- **Traces**: [Jaeger UI](http://localhost:16686)
 - **Logs**: Check terminal output (structured JSON in production)
-- **Sentry**: https://sentry.io (if configured)
+- **Sentry**: [Sentry Dashboard](https://sentry.io) (if configured)

---

134-151: Specify language for file structure tree.

The key files structure would benefit from a language specifier for better rendering.

-```
+```text
 ├── backend/src/

backend/prisma/migrations/20250117000000_init/migration.sql (2)

1-14: LGTM! Schema foundation is solid.

The enum and Episode table structure are well-designed. The use of JSONB for seedInput and outline provides flexibility for evolving schemas.

Consider these optional enhancements for future iterations:

1. Add CHECK constraint to validate UUID format for id fields if using UUIDs
2. Consider creating an enum for rendererModel if values are constrained (e.g., 'gemini', 'openai')
3. Add JSONB schema validation using CHECK constraints if specific fields in seedInput/outline are always required

---

46-74: Index strategy is solid for initial deployment.

The indexes cover common query patterns effectively:

• Episode lookups by time range (createdAt, updatedAt)
• Page filtering by episode and status
• Unique constraints prevent data integrity issues

For future optimization, consider adding indexes based on actual query patterns:

1. Page(createdAt) or Page(updatedAt) if querying pages by time
2. Character(name) if searching characters by name
3. Consider partial indexes like CREATE INDEX ON Page(episodeId) WHERE status = 'failed' for monitoring failed pages

Monitor query performance in production and add indexes as needed.

backend/src/observability/correlation.interceptor.ts (2)

1-34: Correlation ID logic is correct and well-implemented.

The interceptor properly:

• Checks multiple common headers for correlation IDs
• Generates a secure UUID fallback
• Attaches the ID to both request and response for end-to-end tracking

Consider adding TypeScript type augmentation for request.correlationId to improve type safety:

Create a file backend/src/observability/types.ts:

import { Request } from 'express';

declare module 'express' {
  interface Request {
    correlationId?: string;
  }
}

Then import it in this file or in a global types file.

---

52-71: Error logging is robust with good defensive programming.

The error handler correctly:

• Logs errors without suppressing them (tap doesn't catch)
• Uses fallback status code (500) when not set
• Captures stack traces for debugging

For extra safety, add null-check for response object in case of early-stage errors:

  error: (error) => {
    const latency = Date.now() - startTime;
+   const statusCode = response?.statusCode || 500;
    this.logger.logStructured(
      'error',
      {
        correlation_id: correlationId,
        http_method: method,
        http_url: url,
-       http_status: response.statusCode || 500,
+       http_status: statusCode,
        latency_ms: latency,
        request_type: 'http_request',
        error: error.message,
        error_stack: error.stack,
      },
      `${method} ${url} ERROR - ${latency}ms`,
    );
  },

observability-alerts.yml (1)

86-145: Cost and business alerts provide good operational visibility.

The alerts cover key business metrics effectively. The success rate threshold (95%) establishes a clear SLO.

Customize the HighAICost threshold based on your actual budget:

  - alert: HighAICost
    expr: |
      (
        rate(ai_cost_usd_total[1h]) * 3600 * 24
-     ) > 100
+     ) > YOUR_DAILY_BUDGET  # e.g., 50, 200, 500, etc.
    for: 1h

Also consider adding tiered cost alerts:

• Warning at 50% of budget
• Critical at 80% of budget
• Page at 100% of budget

backend/package.json (1)

10-21: Scripts and dependency wiring look coherent with new Prisma/observability stack

The added Prisma scripts, prisma seed entry, and new telemetry/queue/export-related dependencies are consistent with the rest of the PR (worker, queue, export, observability). Nothing blocking here.

If you end up adding more TS-based CLIs, consider centralizing ts-node/ts-node-dev options (e.g., via a shared env or small wrapper) to avoid drift across scripts.

Also applies to: 27-52, 54-60

backend/src/worker/generate.worker.ts (6)

30-44: Hard failure on missing REDIS_URL is appropriate, but consider logging env overview

Exiting when REDIS_URL is missing is reasonable for a pure worker process. If you later add more env-based behavior (e.g., optional queues), consider logging a brief “worker disabled” vs process.exit(1) in dev/local to make misconfiguration less abrupt.

---

48-49: Prisma gating is mostly explicit, but page processing strictly requires DB

prisma is only instantiated when DATABASE_URL is set, and processPageJob correctly throws if !prisma before DB access. That makes page generation strictly dependent on DB being configured, which is consistent but slightly different from the character path (which just skips DB updates when !prisma).

If you want a clearer contract, you could either:

• Fail startup up-front when DATABASE_URL is missing but workers are expected to be used, or
• Log a clear warning at startup that page jobs will fail without DB, instead of discovering it at runtime inside each job.

Also applies to: 292-303, 367-381

---

109-137: Renderer service: good provider abstraction; think about client reuse and error context

The provider switch and separation between Gemini/OpenAI methods is clean. Two small improvements you might consider:

• Reuse clients instead of constructing a new Gemini/OpenAI client on each call (cache them in private fields after first access).
• Add more context to thrown errors (e.g., include episodeId/pageNumber passed in) to make logs more actionable when debugging generation failures.

Also applies to: 139-170, 172-210

---

212-270: Character image generation mirrors page flow; DB write is guarded but errors always rethrown

The character job processor correctly:

• Uses renderer.generateCharacterImage.
• Conditionally updates Prisma when available.
• Rethrows errors after logging, letting BullMQ handle retries.

Given page jobs emit rich SSE events on failure, you might eventually want analogous event emission for character jobs so the frontend can reflect character generation status too.

---

277-416: Page job: good progress events and DB updates; minor prompt/outline robustness

The page processor has a solid flow: progress events, outline lookup, prompt building, renderer call, DB update, final page_done event, and error path updating status + page_failed event.

Two minor robustness ideas:

• Guard against outline.pages not being an array (e.g., invalid JSON or unexpected shape) before find, and log a clearer error if so.
• When pageOutline.key_actions isn’t an array, join will throw; consider coercing to array or defaulting to '' more defensively.

---

451-459: Worker lifecycle and graceful shutdown look solid

You correctly:

• Instantiate independent workers for page/character queues with configurable concurrency.
• Attach basic lifecycle logging.
• On shutdown, close workers, QueueEvents, Redis publisher, and Prisma.

One small improvement: wrap shutdown body in a try/catch and avoid calling process.exit(0) from inside the handler so Nest/bullmq can finish any in-flight work if you ever integrate this into a larger process; here, since it’s a standalone worker, this is acceptable.

Also applies to: 461-474, 477-494

backend/src/episodes/episodes.controller.ts (2)

74-80: Export endpoint uses POST; consider whether GET would be more REST‑like

Using POST /episodes/:id/export for a read-only file generation is acceptable, especially if export has side effects (e.g., caching, logging). If it’s purely deterministic and side‑effect free, you might consider GET for better alignment with HTTP semantics and easier browser use.

---

81-102: Input validation and early error responses look good

Format/episode/pages validation with clear 4xx responses is solid. Using includeAudio as a string flag is fine; if this grows, you might eventually formalize query validation (e.g., with pipes/zod), but nothing blocking.

backend/src/queue/queue-events-bridge.service.ts (4)

31-59: Redis subscription and message forwarding look correct; minor robustness nits

You correctly:

• Use a dedicated subscriber connection.
• Subscribe to worker:events.
• Parse JSON and forward to EventsService only when episodeId and type exist.

Two small robustness improvements you might consider:

• Narrow the JSON.parse type to Partial<EventPayload> (or a lightweight shape) before casting, to avoid accidental runtime mismatches.
• Add a guard/log when the payload is structurally invalid but JSON parses (e.g., missing episodeId), so those messages aren’t silently ignored.

---

60-83: QueueEvents lifecycle listeners provide useful observability

Attaching active/completed/failed/progress listeners for both queues with the setupJobEventListeners helper is straightforward and keeps logging concerns centralized. Looks good.

If logs get noisy under load, you might later gate progress logging behind a debug flag.

---

87-103: Job event logging could benefit from structured context rather than concatenated strings

Logging with template strings is fine, but using structured logging (fields for queueType, jobId, status) would integrate better with pino/observability tooling introduced elsewhere in the PR.

---

105-116: Static emitWorkerEvent helper duplicates worker‑side publisher logic

The static helper is a nice utility, but generate.worker.ts currently instantiates its own Redis publisher instead of calling this. That’s okay, but it does mean two patterns for emitting worker events.

If you want to DRY things up, consider:

• Importing QueueEventsBridgeService into the worker and using emitWorkerEvent, or
• Extracting a tiny shared worker-events-publisher module that both the worker and this service use.

backend/src/planner/planner.fallback.ts (3)

77-100: Consider centralizing page-count constant and enriching prompts (optional)

The stub outline assumes exactly 10 pages in both the generator and mergeWithStub. This matches the rest of the codebase today but is implicitly duplicated here. If you ever support variable episode lengths, this will be an easy place to forget to update.

Optional improvements:

• Extract a shared TOTAL_PAGES = 10 constant used by planner, episodes service, and UI.
• Optionally tailor key_actions / beat more per page index to produce slightly richer stub output (not required for correctness).

Also applies to: 103-106

---

112-129: Avoid duplicating filename sanitization logic (optional)

sanitizeFilename here is very similar to the helper in backend/src/episodes/episodes.service.ts, but with slightly different underscore/extension handling. This can drift over time and produce mismatched asset filenames between planner output and episode logic.

If feasible, consider extracting a shared utility for character asset filename sanitization and reusing it from both places, so planner and episodes/export all agree on filename rules.

---

135-181: mergeWithStub behavior is sensible; consider minimal page validation extensions (optional)

The merge logic cleanly:

• Prefers AI characters when present, otherwise uses stub characters.
• Validates AI pages for core fields and falls back to stub pages when missing/invalid.
• Always returns a full 10-page outline.

You might optionally tighten validation (e.g., ensure aiPage.page_number matches pageNumber, or validate layout_hints.panels / dialogue array contents) to avoid accepting structurally inconsistent AI pages, but the current minimum required fields are a reasonable baseline for now.

pages/episodes/[id].tsx (1)

193-230: Export flow is robust; minor filename fallback nit

The export handler:

• Validates id shape.
• Handles non‑OK responses by attempting to parse a { error } payload and surfacing a meaningful message.
• Safely extracts a filename from Content-Disposition, falling back to a sensible default.
• Performs the blob download via a temporary <a> element and revokes the object URL afterward.
• Correctly manages isExporting and closes the modal on success.

This is solid. One tiny nit: the fallback episode_${exportFormat}.${exportFormat} leads to names like episode_pdf.pdf; using episode.${exportFormat} would read slightly more naturally, but the current behavior is functionally fine.

backend/DATABASE_SETUP.md (1)

126-129: Add languages to fenced code blocks to satisfy markdownlint and improve readability

A few code fences are missing language specifiers (e.g., the connection string example and the error message snippets under “Connection Refused”, “Authentication Failed”, “Migration Conflicts”, “Out of Connections”). This triggers MD040 and slightly degrades syntax highlighting.

Suggested fixes:

• For the connection string format: use something like text or bash.
• For error message snippets: use ```text.
• For any SQL examples: use ```sql (already used elsewhere, but ensure consistency).

Applying language tags to all fenced blocks will clear the lint warnings and make the guide more readable.

Also applies to: 338-341, 349-352, 360-363, 371-373

backend/src/queue/queue.service.ts (1)

173-185: Consider closing BullMQ queues on shutdown (optional lifecycle refactor)

cleanQueues, pauseQueues, and resumeQueues are implemented sensibly and gated by enabled. One lifecycle enhancement to consider:

• Implement OnModuleDestroy in QueueService and call await this.pageQueue?.close() / await this.characterQueue?.close() to ensure connections are released cleanly on app shutdown, especially in environments where the NestJS process is frequently recycled.

Not critical, but it can prevent lingering connections in long-running or frequently-restarted deployments.

Also applies to: 189-205

ARCHITECTURE_VERIFICATION_REPORT.md (1)

278-283: Tighten markdown formatting for tables and fenced blocks

The content is solid; a couple of small markdown issues flagged by tooling would be easy wins:

• Several tables (for integrations, feature flags, health scores, etc.) are not surrounded by blank lines, which triggers MD058 and can affect some renderers.
• Some fenced code blocks (e.g., ASCII diagrams / shell snippets) lack an explicit language, which triggers MD040. Adding ts, bash, or text where appropriate will quiet linters and improve highlighting.

This is purely cosmetic but will keep markdownlint/CI green.

Also applies to: 379-385, 421-435, 471-483, 610-621

backend/src/observability/instrumentation-helpers.ts (1)

11-24: Harden helpers against edge cases and improve attribute handling

The helpers look good overall; a few small changes would make them more robust:

• In calculateAICost, unknown providers/models silently return 0. That’s fine as a fallback, but consider logging or tagging these cases so you can detect misconfigurations instead of quietly under-reporting cost.

• In addMangaAttributes, the pattern ...(data.pageNumber && { 'manga.page_number': data.pageNumber }) will drop pageNumber = 0. If you ever use 0-based numbering, prefer an explicit null check:

-    ...(data.pageNumber && { 'manga.page_number': data.pageNumber }),
+    ...(data.pageNumber !== undefined && { 'manga.page_number': data.pageNumber }),

• categorizeError assumes error.message is a string and calls .toLowerCase() directly. If something non-Error is thrown, this will itself throw. You can defensively guard:

-  const message = error.message.toLowerCase();
+  const msg = typeof (error as any).message === 'string' ? (error as any).message : String(error);
+  const message = msg.toLowerCase();

• In extractErrorMetadata, JSON.stringify(error.response) can throw if the payload is very large or circular. Wrapping it in a try/catch and truncating on success (as you already do) would avoid logging-time failures.

These are all non-breaking tweaks that make observability paths safer under unexpected errors.

Also applies to: 29-60, 65-81, 115-153, 158-181

lib/observability/api-wrapper.ts (1)

17-23: Modernize correlation ID generation (avoid substr)

getCorrelationId uses Math.random().toString(36).substr(2, 9). substr is deprecated; switching to slice avoids deprecation warnings and keeps behavior:

-    `web-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`
+    `web-${Date.now()}-${Math.random().toString(36).slice(2, 11)}`

Functionally identical, but more future-proof.

backend/src/export/export.service.ts (1)

147-249: Refactor exportAsCBZ to avoid async Promise executor

exportAsCBZ currently does:

return new Promise(async (resolve, reject) => {
  try {
    // await inside...
  } catch (error) {
    reject(error);
  }
});

Using async on a Promise executor is a common anti-pattern and is flagged by Biome (noAsyncPromiseExecutor). It can make control-flow harder to reason about and isn’t needed here.

You can keep the same behavior by using a non-async executor and moving the await logic into an inner IIFE:

-  async exportAsCBZ(options: ExportOptions): Promise<ExportResult> {
-    const { episodeTitle, pages, includeAudio } = options;
-
-    return new Promise(async (resolve, reject) => {
-      try {
+  async exportAsCBZ(options: ExportOptions): Promise<ExportResult> {
+    const { episodeTitle, pages, includeAudio } = options;
+
+    return new Promise<ExportResult>((resolve, reject) => {
+      const tempDir = path.join(
+        os.tmpdir(),
+        `cbz_${Date.now()}_${Math.random().toString(36).slice(2)}`,
+      );
+      fs.mkdirSync(tempDir, { recursive: true });
+
+      const archive = archiver('zip', { zlib: { level: 9 } });
+      const chunks: Buffer[] = [];
+
+      archive.on('data', (chunk: Buffer) => {
+        chunks.push(chunk);
+      });
+
+      archive.on('end', () => {
+        const buffer = Buffer.concat(chunks);
+        const sanitizedTitle = this.sanitizeFilename(episodeTitle);
+        const filename = `${sanitizedTitle}_manga.cbz`;
+        this.cleanupTempDir(tempDir);
+        resolve({
+          buffer,
+          filename,
+          mimeType: 'application/x-cbz',
+          size: buffer.length,
+        });
+      });
+
+      archive.on('error', (err: Error) => {
+        this.cleanupTempDir(tempDir);
+        reject(err);
+      });
+
+      (async () => {
+        try {
+          const comicInfo = this.generateComicInfoXml(episodeTitle, pages.length);
+          archive.append(comicInfo, { name: 'ComicInfo.xml' });
+
+          for (const page of pages) {
+            if (!page.imageUrl) {
+              console.warn(`Page ${page.pageNumber} has no image, skipping`);
+              continue;
+            }
+
+            try {
+              const imageBytes = await this.downloadImage(page.imageUrl);
+              const ext =
+                page.imageUrl.match(/\.(png|jpg|jpeg|webp)(\?|$)/i)?.[1] || 'png';
+              const paddedNumber = String(page.pageNumber).padStart(3, '0');
+              const imageName = `page_${paddedNumber}.${ext}`;
+              archive.append(imageBytes, { name: imageName });
+              console.log(`Added ${imageName} to CBZ`);
+            } catch (error) {
+              console.error(
+                `Error adding page ${page.pageNumber} to CBZ:`,
+                error,
+              );
+            }
+          }
+
+          if (includeAudio) {
+            const audioDir = 'audio/';
+            let hasAudio = false;
+            for (const page of pages) {
+              if (!page.audioUrl) continue;
+              try {
+                const audioBytes = await this.downloadAudio(page.audioUrl);
+                const paddedNumber = String(page.pageNumber).padStart(3, '0');
+                const audioName = `${audioDir}page_${paddedNumber}.mp3`;
+                archive.append(audioBytes, { name: audioName });
+                hasAudio = true;
+                console.log(`Added ${audioName} to CBZ`);
+              } catch (error) {
+                console.error(
+                  `Error adding audio for page ${page.pageNumber}:`,
+                  error,
+                );
+              }
+            }
+            if (hasAudio) {
+              const audioReadme = `Audio Files for ${episodeTitle}\n\nThis CBZ archive includes audiobook narration for each page.\nAudio files are located in the 'audio/' directory.\n\nFile naming: page_XXX.mp3 corresponds to page_XXX.png\n`;
+              archive.append(audioReadme, { name: 'audio/README.txt' });
+            }
+          }
+
+          archive.finalize();
+        } catch (error) {
+          this.cleanupTempDir(tempDir);
+          reject(error as Error);
+        }
+      })();
-      } catch (error) {
-        reject(error);
-      }
-    });
+    });
   }

This satisfies the linter and keeps the control flow explicit around archive events and cleanup.

OBSERVABILITY.md (1)

28-72: Tighten Markdown linting: add languages to fences and avoid bare URLs

The content is excellent; a few small tweaks will keep markdownlint happy and improve readability:

• Add explicit languages to the “unstyled” fenced blocks (ASCII diagram, .env snippets, log snippets), e.g. ```text, ```bash, or ```env at lines like 28, 234, 243, 253, 272, 528, 563.
• Replace bare URLs (e.g. Jaeger http://localhost:16686, OpenAI/Google pricing links) with markdown links like [Jaeger UI](http://localhost:16686) and [OpenAI pricing](https://openai.com/pricing) to satisfy MD034.

Example (illustrative):

-```
+```text
 ┌─────────────────────────────────────────────────────────────┐
 ...
 └─────────────────────────────────────────────────────────────┘
-```
+```
@@
-OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4318/v1/traces
-```
+OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4318/v1/traces
+```bash
@@
-For Jaeger: Visit http://localhost:16686
+For Jaeger: Visit [http://localhost:16686](http://localhost:16686)

Also applies to: 234-247, 253-256, 272-276, 280-283, 496-497, 528-531, 563-566

backend/src/episodes/episodes.service.ts (3)

572-679: Consider replacing console logging with structured logging in character generation

Within generateCharacters, character generation failures and progress are logged via console.warn (in the in‑process branch). For consistency with the observability stack (Pino + LoggerService) and better correlation with traces, it would be preferable to use the injected logger (or the shared LoggerService) instead of raw console calls.

This is non‑blocking but will help keep logs centralized and structured.

---

409-411: Sleep helper duplicates planner.utils.sleep

EpisodesService defines a local private sleep(ms: number) helper, while backend/src/planner/planner.utils.ts exports a similar sleep utility. Not critical, but you might consider moving sleep to a shared utility module and reusing it here to avoid duplication.

---

721-755: Dialogue retrieval prioritization (override → DB overlays → planner outline) is sensible

getPageDialogue prioritizes in‑memory overrides, then persisted overrides in the page’s overlays JSON, and finally falls back to the planner outline dialogues. The parseDialogueLines helper cleanly supports “name: text” and narration lines.

One minor note: parseDialogueLines returns character: null for narration, which differs from the PanelDialogueSchema’s character?: string (string or undefined). This doesn’t break runtime behavior, but if you start validating these lines with Zod, you may want to normalize narration to use undefined instead of null.

backend/src/planner/planner.utils.ts (4)

13-78: Retry utilities are functionally sound

RetryConfig, calculateBackoff, and withRetry implement a straightforward exponential backoff with a max delay and proper propagation of the last error. The behavior on success-after-retries and final failure is clear.

You may eventually want to swap console.log/error for the shared LoggerService and/or TracingService so retries show up in structured logs and traces, but the current implementation is correct.

---

83-193: Multi-strategy JSON extraction is robust for LLM responses

The layered strategies in extractJson (direct parse, trimmed parse, {...} slice, code fences, balanced braces, cleaned braces) cover most malformed AI response shapes, with clear error aggregation when all strategies fail. This is a good balance of resilience and debuggability for planner outputs.

---

198-237: JSON repair heuristics are reasonable but aggressive—monitor for false positives

repairJson’s transformations (removing trailing commas, stripping comments, converting single‑quoted strings) are a pragmatic way to rescue common AI mistakes before re‑parsing. They can, in theory, mis-handle valid payloads with embedded single quotes or comment‑like text, but since they only run after initial extraction fails, the tradeoff seems acceptable.

It might be worth logging the original vs repaired snippets somewhere (with truncation) via structured logging if you need to debug repair behavior in production.

---

254-311: PlannerMetrics gives useful high-level stats

PlannerMetrics cleanly tracks successes/failures, retry successes, and error categories, and exposes both a structured getStats and a simple logStats. This should be handy for planner tuning. Later, you could feed these metrics into your observability stack (e.g., LoggerService or custom metrics) in addition to console.log.

backend/src/planner/planner.service.ts (4)

59-65: Validate retry config from env and fall back to sane defaults

parseInt/parseFloat on the PLANNER_* env vars can yield NaN or non‑positive values, which would make withRetry behave oddly (e.g., loop never running when maxAttempts is NaN or <= 0). Consider validating each value and falling back to DEFAULT_RETRY_CONFIG (or clamped bounds) when parsing fails instead of trusting raw envs. A small helper to build a safe RetryConfig from env would keep this robust.

---

87-122: Clarify stub fallback semantics for callers (EpisodesService, SSE)

generateOutline now performs an internal stub fallback and returns a valid outline when enableStubFallback is true, rather than propagating failures. EpisodesService.planEpisode still wraps planner.generateOutline in a try/catch and reports “Using fallback story template...” on error. With this new behavior, callers can’t distinguish “real AI outline” from “stub fallback” and may never emit that progress event.

If you care about surfacing fallback usage to clients, consider:

• Returning metadata (e.g., { outline, usedFallback: boolean }) or
• Letting errors bubble and moving stub fallback up into EpisodesService.

Right now the behavior is logically correct but slightly opaque for downstream observability/UX.

---

56-57: Align metrics logging with LoggerService instead of raw console

PlannerMetrics.logStats() currently writes directly to console.log, and generateOutline calls it in finally. Given you already depend on LoggerService, this bypasses your structured logging/observability stack.

Two options:

• Inject LoggerService (or a generic logger) into PlannerMetrics and log via logger.debug/info, or
• Stop calling logStats() here and rely on getMetrics() + higher‑level logging/export instead.

Either way, consolidating on a single logging mechanism will make metrics easier to consume and control.

Also applies to: 124-125, 393-395

---

310-356: Make the example schema JSON syntactically valid to avoid confusing the model

The schema string in buildPrompt includes non‑JSON syntax ("panels": 3-6 and the // up to page 10 comment). It’s only used as instructional text, but you also emphasize “STRICT JSON” in the prompt. Cleaning this up (e.g., use "panels": 3 with a separate bullet explaining “3–6 panels” and remove the // comment) will keep the example consistent with the constraints you’re asking the model to follow.

Also applies to: 371-375

EXPORT_FEATURE.md (1)

114-126: Add languages to fenced code blocks for markdownlint and readability

The CBZ directory structure block uses a bare triple‑backtick fence. To satisfy markdownlint (MD040) and aid rendering, consider tagging it with a language (e.g., ```text) and doing the same wherever you have anonymous fences in this doc.

QUEUE_FILES_SUMMARY.txt (1)

5-39: Prefer repo‑relative paths over local absolute paths in the summary

The file lists paths like /home/user/mangafusion/backend/src/queue/queue.service.ts. For collaborators and CI environments these are misleading; switching to repo‑relative paths (e.g., backend/src/queue/queue.service.ts) would make this summary more portable and future‑proof.

backend/src/planner/IMPLEMENTATION_SUMMARY.md (1)

62-68: Tidy up markdown fences and paths in the implementation summary

A few code fences here (e.g., the retry sequence and example log output) use bare ``` fences, which markdownlint flags (MD040). Tagging them with an appropriate language like bash, `ts`, or `text` will clear the warnings and improve rendering. Also, consider converting absolute paths such as `/home/user/mangafusion/backend/src/planner/...` to repo‑relative paths so the doc stays accurate for all environments.

Also applies to: 146-152, 303-323

backend/src/planner/planner.service.hardened.ts (1)

20-386: Verifying additional edge cases for imports and confirming the file's intended status:

Now checking if the codebase intentionally maintains reference implementations:

Based on verification, the script output and documentation review show:

1. No imports detected: The hardened variant is not imported anywhere in runtime code
2. Correct DI wiring: planner.module.ts imports the canonical ./planner.service (not the hardened variant)
3. Explicitly labeled: The file is documented as "Reference implementation" in FEATURES_IMPLEMENTATION_SUMMARY.md and IMPLEMENTATION_SUMMARY.md
4. Clear intent: The .hardened.ts suffix and documentation label make the non-runtime status apparent

The original concern about accidental imports is unfounded given the current import patterns. However, keeping reference implementations within src/ alongside active code is still suboptimal by NestJS best practices.

---

Move planner.service.hardened.ts outside src/ or add TSDoc disclaimer

This file is labeled as a reference implementation in documentation but stored in src/ where code is expected to be active. While no imports currently target this variant, the location creates maintenance ambiguity. Either:

• Move to docs/examples/ or a non-runtime directory, or
• Add a prominent TSDoc comment: /** @deprecated Reference implementation only. Use planner.service.ts instead. */

This clarifies intent for future contributors and aligns with NestJS conventions.

IMPLEMENTATION_SUMMARY.md (1)

97-102: Environment variable documentation is minimal.

The DATABASE_URL example is helpful, but the summary should clarify:

• What happens if DATABASE_URL is not set? (Falls back to in-memory mode?)
• Are there other environment variables required (e.g., for connection pooling, SSL, timeouts)?
• Should DATABASE_URL be treated as a secret (no logging, no commits)?
• Are there validation or format requirements for the connection string?

Consider expanding this section or cross-referencing more detailed environment setup documentation.

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

Pages mapping assumes pageNumber and audioUrl shape; consider type tightening

The mapping to { pageNumber, imageUrl, audioUrl } with (p as any).audioUrl will break silently if the Prisma model or DTO changes.

Consider:

• Defining an explicit DTO/interface for exportable pages including audioUrl?, and
• Letting EpisodesService expose pages already in that shape instead of casting to any here.

🤖 Prompt for AI Agents

In backend/src/episodes/episodes.controller.ts around lines 104 to 123, the
current mapping uses (p as any).audioUrl and assumes pageNumber/imageUrl exist
which is brittle; define an explicit ExportablePage interface (pageNumber:
number, imageUrl: string, audioUrl?: string) and update EpisodesService to
return pages typed as ExportablePage[] (or provide a conversion method there).
Replace the inline cast and mapping with a typed value from EpisodesService (or
map from a strongly-typed source) so the controller no longer uses any and the
compiler will catch missing fields or shape changes.

[coderabbitai]

⚠️ Potential issue | 🔴 Critical

🧩 Analysis chain

Fix LoggerService constructor to avoid NestJS DI resolution errors

LoggerService is marked @Injectable() and used as a Nest provider, but its constructor takes a primitive string (context?: string) with no @Inject/@Optional decorator. Nest will attempt to resolve a provider for String, which typically results in a runtime error when instantiating the service.

Given the current usage (consumers call logger.child({ context: 'PlannerService' })), you don’t need constructor-based context injection. A parameterless constructor keeps DI simple and preserves the child-logger pattern.

Suggested change:

-  constructor(context?: string) {
+  constructor() {
     this.logger = pino({
       level: process.env.LOG_LEVEL || (this.isProduction ? 'info' : 'debug'),
       formatters: {
         level: (label) => {
           return { level: label };
         },
       },
       ...(this.isProduction
         ? {
             // Production: JSON output
             timestamp: pino.stdTimeFunctions.isoTime,
           }
         : {
             // Development: Pretty output
             transport: {
               target: 'pino-pretty',
               options: {
                 colorize: true,
                 translateTime: 'HH:MM:ss.l',
                 ignore: 'pid,hostname',
               },
             },
           }),
     });
-
-    if (context) {
-      this.logger = this.logger.child({ context });
-    }
   }

   /**
    * Create a child logger with additional context
    */
   child(bindings: Record<string, any>): LoggerService {
-    const childLogger = new LoggerService();
-    childLogger.logger = this.logger.child(bindings);
-    return childLogger;
+    const childLogger = new LoggerService();
+    childLogger.logger = this.logger.child(bindings);
+    return childLogger;
   }

This avoids DI issues while preserving the existing child() behavior.

Also applies to: 60-64

---

🏁 Script executed:

#!/bin/bash
# Inspect how LoggerService is provided and injected to confirm DI wiring.
rg -n "LoggerService" backend/src/observability -C5

Length of output: 7812

---

I need to verify if there are any non-test files that directly instantiate LoggerService with the context parameter:

Fix LoggerService constructor to avoid NestJS DI resolution errors

NestJS requires the @optional decorator on constructor parameters to properly handle optional dependencies. LoggerService has a constructor parameter context?: string without any DI decorator. NestJS scans each class to find injection tokens, and without @Optional or @Inject, it will attempt to resolve a String provider, which doesn't exist. This causes DI instantiation failure when CorrelationInterceptor (line 14 in correlation.interceptor.ts) tries to inject the service.

The child() method already calls new LoggerService() parameterlessly (line 61), so removing the constructor parameter preserves the child-logger pattern while avoiding the DI error.

Suggested change:

-  constructor(context?: string) {
+  constructor() {
     this.logger = pino({
       level: process.env.LOG_LEVEL || (this.isProduction ? 'info' : 'debug'),
       formatters: {
         level: (label) => {
           return { level: label };
         },
       },
       ...(this.isProduction
         ? {
             // Production: JSON output
             timestamp: pino.stdTimeFunctions.isoTime,
           }
         : {
             // Development: Pretty output
             transport: {
               target: 'pino-pretty',
               options: {
                 colorize: true,
                 translateTime: 'HH:MM:ss.l',
                 ignore: 'pid,hostname',
               },
             },
           }),
     });
-
-    if (context) {
-      this.logger = this.logger.child({ context });
-    }
   }

🤖 Prompt for AI Agents

backend/src/observability/logger.service.ts lines 1-39: Remove the constructor
parameter "context?: string" so Nest's DI won't try to resolve a string token;
make the constructor parameterless and instead implement/adjust the class's
child-creation logic so callers that need a contextual logger call a method like
child(context: string) that returns a new LoggerService instance whose internal
pino logger is created via this.logger.child({ context }) (i.e., keep
constructor parameterless for DI, move context handling into a dedicated
child(...) method and ensure all call sites use that method or create instances
without constructor args).

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

🧩 Analysis chain

Excellent documentation structure and completeness.

The implementation report provides a comprehensive overview with clear sections, file inventory, and line counts. The production-ready status claim is well-supported by the extensive documentation.

Verify that all 22 listed files actually exist and contain the expected functionality:

---

🏁 Script executed:

#!/bin/bash
# Verify existence of key observability files
echo "Checking backend observability files..."
for file in \
  "backend/src/instrumentation.ts" \
  "backend/src/observability/logger.service.ts" \
  "backend/src/observability/tracing.service.ts" \
  "backend/src/observability/correlation.interceptor.ts" \
  "backend/src/observability/observability.module.ts" \
  "backend/src/observability/instrumentation-helpers.ts" \
  "backend/src/observability/test-observability.ts"; do
  if [ -f "$file" ]; then
    echo "✓ $file exists ($(wc -l < "$file") lines)"
  else
    echo "✗ $file MISSING"
  fi
done

echo -e "\nChecking frontend observability files..."
for file in \
  "sentry.client.config.ts" \
  "sentry.server.config.ts" \
  "sentry.edge.config.ts" \
  "lib/observability/api-wrapper.ts" \
  "pages/api/observability-test.ts"; do
  if [ -f "$file" ]; then
    echo "✓ $file exists"
  else
    echo "✗ $file MISSING"
  fi
done

Length of output: 729

---

Partial verification complete. All 12 checked backend/frontend files exist, but with inaccurate line counts in the report. Need to verify remaining 10 files (documentation and modified files).

---

🏁 Script executed:

#!/bin/bash
echo "Checking documentation files..."
for file in \
  "OBSERVABILITY.md" \
  "OBSERVABILITY_QUICK_START.md" \
  "OBSERVABILITY_IMPLEMENTATION_SUMMARY.md" \
  "OBSERVABILITY_FILES_INDEX.md" \
  ".env.observability.example" \
  "observability-alerts.yml"; do
  if [ -f "$file" ]; then
    echo "✓ $file exists ($(wc -l < "$file") lines)"
  else
    echo "✗ $file MISSING"
  fi
done

echo -e "\nChecking modified files..."
for file in \
  "backend/src/main.ts" \
  "backend/src/app.module.ts" \
  "backend/src/planner/planner.service.ts"; do
  if [ -f "$file" ]; then
    echo "✓ $file exists"
  else
    echo "✗ $file MISSING"
  fi
done

echo -e "\nChecking dashboard config..."
if [ -f "backend/observability-dashboard.json" ]; then
  echo "✓ backend/observability-dashboard.json exists"
else
  echo "✗ backend/observability-dashboard.json MISSING"
fi

Length of output: 540

---

Update line counts in the documentation to reflect actual implementation.

All 22 claimed files exist and are in place. However, the line counts in the report contain inaccuracies:

• Created files have variances ranging from -4 to +49 lines (e.g., logger.service.ts: 160 vs 145, tracing.service.ts: 205 vs 156)
• observability-alerts.yml: 286 vs 259 lines (+27)
• OBSERVABILITY_IMPLEMENTATION_SUMMARY.md: 842 lines (claimed "500+", understated)

Update the line counts in OBSERVABILITY_IMPLEMENTATION_REPORT.txt lines 17–47 to match the actual file sizes to ensure documentation accuracy.

🤖 Prompt for AI Agents

In OBSERVABILITY_IMPLEMENTATION_REPORT.txt around lines 17 to 47, the documented
line counts for created/modified files are inaccurate; update those counts to
the actual file sizes by computing each file's current line count (e.g., use wc
-l or your editor's line count) and replace the reported numbers for the listed
files (backend/src/observability/logger.service.ts,
backend/src/observability/tracing.service.ts, observability-alerts.yml,
OBSERVABILITY_IMPLEMENTATION_SUMMARY.md and any other entries in that range) so
the report reflects the real counts and the total lines/files summary is
adjusted accordingly.

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

Platform-specific command could cause confusion.

The database setup command sudo -u postgres createdb mangafusion is Linux-specific and won't work on macOS (which uses a different user model) or Windows (which doesn't have sudo).

Consider adding a note about platform differences or providing alternatives:

 4. **(Optional) Set up PostgreSQL Database:**
    ```bash
-   # Create database
+   # Create database (Linux)
    sudo -u postgres createdb mangafusion
+   
+   # Or on macOS/Windows, use psql:
+   # psql -U postgres -c "CREATE DATABASE mangafusion;"

Alternatively, reference platform-specific instructions in the DATABASE_SETUP.md guide.

🤖 Prompt for AI Agents

In README.md around lines 68 to 85, the database creation command is
Linux-specific (uses sudo -u postgres) and may confuse macOS/Windows users;
update the section to note platform differences and provide alternative commands
or refer to backend/DATABASE_SETUP.md for platform-specific instructions:
explicitly label the shown command as Linux, add an alternative using psql to
create the database for macOS/Windows (with a brief example invocation), and/or
link to a detailed platform-specific subsection in DATABASE_SETUP.md so users on
non-Linux systems have clear steps.

[coderabbitai]

Actionable comments posted: 6

🧹 Nitpick comments (6)

backend/src/queue/queue-events-bridge.service.ts (3)

23-59: Redis bridge initialization and SSE forwarding are solid; consider stronger payload validation

The gating on REDIS_URL, scoped subscriber, and forwarding into EventsService look good. To harden this path, you might:

• Add a small runtime validator/type guard for the parsed event before casting to EventPayload (e.g., ensure episodeId is a string and type is one of the known event types), so malformed worker messages can be detected explicitly instead of silently dropped.
• Split parsing vs. forwarding errors so the catch block can log a more accurate message (e.g., "Failed to handle worker event" vs. "Failed to parse worker event"), which helps when debugging downstream eventsService.emit failures.

---

74-85: Consider defensive shutdown around Redis and QueueEvents teardown

onModuleDestroy correctly quits the Redis subscriber and closes both QueueEvents instances. To make shutdown more robust, you could wrap each quit/close call in a small try/catch (with debug-level logging) so transient network errors during shutdown don’t bubble up and interfere with NestJS’s module teardown sequence.

---

105-147: Promote channel constant to static field and adopt consistent logging in static methods

The singleton pattern is solid. Two refinements improve maintainability:

• Channel name 'worker:events' appears hard-coded in three places (line 145, generate.worker.ts line 56, and line 19 as an instance field). Promote to a static constant at class or module level to ensure single source of truth and prevent drift across the codebase.
• The static getPublisher() error handler uses console.error while instance methods consistently use the Nest Logger. Add a static logger instance to maintain logging consistency throughout the service.

backend/src/worker/generate.worker.ts (1)

317-318: Define types for JSON fields to improve type safety.

The outline field is cast to any and then accessed with optional chaining, which eliminates type safety. Since the structure is known (pages array with page_number, beat, setting, etc.), define a proper TypeScript interface.

Create a type definition file or add to the worker file:

interface PageOutline {
  page_number: number;
  beat?: string;
  setting?: string;
  key_actions?: string[];
  visual_style?: string;
}

interface EpisodeOutline {
  pages?: PageOutline[];
}

// Then use it:
const outline = episode.outline as EpisodeOutline;
const pageOutline = outline?.pages?.find((p) => p.page_number === pageNumber);

Also applies to: 331-334

backend/src/export/export.service.ts (2)

182-189: Consider memory implications for large exports.

The entire CBZ archive is buffered in memory via the chunks array before being returned. For episodes with many high-resolution images (e.g., 50+ pages at 1024x1536), this could consume 100MB+ of memory per export operation.

For future optimization, consider:

1. Streaming the archive directly to the response (requires controller changes)
2. Writing to a temporary file and streaming from disk
3. Implementing a maximum size limit with appropriate error messages

This is acceptable for the initial implementation but may need optimization for production scale.

---

173-174: Unused temporary directory - consider removing.

A temporary directory is created (line 173) and cleaned up (lines 194, 205), but it's never actually used. The archive appends data directly from memory buffers without writing to the filesystem.

If the temp directory isn't needed, remove its creation and cleanup:

-   const tempDir = path.join(os.tmpdir(), `cbz_${Date.now()}_${Math.random().toString(36).slice(2)}`);
-   fs.mkdirSync(tempDir, { recursive: true });

    return new Promise<ExportResult>((resolve, reject) => {
      // ... archive setup ...

      archive.on('end', () => {
        const buffer = Buffer.concat(chunks);
        const sanitizedTitle = this.sanitizeFilename(episodeTitle);
        const filename = `${sanitizedTitle}_manga.cbz`;

-       this.cleanupTempDir(tempDir);

        resolve({
          buffer,
          filename,
          mimeType: 'application/x-cbz',
          size: buffer.length,
        });
      });

      archive.on('error', (err: Error) => {
-       this.cleanupTempDir(tempDir);
        reject(err);
      });

Alternatively, if you plan to use it for intermediate file storage in the future, keep it but add a comment explaining the intention.

Also applies to: 194-194, 205-205

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 9dcaf71 and 85eb13e.

📒 Files selected for processing (3)

• backend/src/export/export.service.ts (1 hunks)
• backend/src/queue/queue-events-bridge.service.ts (1 hunks)
• backend/src/worker/generate.worker.ts (1 hunks)

🧰 Additional context used

🧬 Code graph analysis (2)

backend/src/worker/generate.worker.ts (2)

backend/src/events/events.service.ts (1)

• EventPayload (5-11)

backend/src/queue/queue.service.ts (2)

• GeneratePageJobData (4-13)
• GenerateCharacterJobData (15-23)

backend/src/queue/queue-events-bridge.service.ts (2)

backend/src/queue/queue.service.ts (1)

• Injectable (25-206)

backend/src/events/events.service.ts (1)

• EventPayload (5-11)

🪛 Biome (2.1.2)

backend/src/export/export.service.ts

[error] 170-269: Promise executor functions should not be async.

(lint/suspicious/noAsyncPromiseExecutor)

🔇 Additional comments (7)

backend/src/worker/generate.worker.ts (3)

396-419: Good error handling pattern with comprehensive cleanup.

The error handling properly updates database state, emits failure events to consumers, logs the error, and re-throws to mark the job as failed in BullMQ. This ensures both persistence and real-time notification of failures.

---

503-524: LGTM! Comprehensive graceful shutdown.

The shutdown handler properly closes all workers, queue events, Redis connections, and Prisma client in the correct order. Listening to both SIGINT and SIGTERM ensures clean termination in various environments (development Ctrl+C, container orchestration, etc.).

---

37-38: LGTM! Sensible concurrency defaults with environment configurability.

The concurrency settings (2 for pages, 1 for characters) align with the documented priority model where character generation has higher priority. Making these configurable via environment variables enables tuning for different deployment environments.

Also applies to: 477-485

backend/src/export/export.service.ts (4)

33-45: LGTM! Robust download error handling with timeouts.

Both download methods implement:

• Reasonable 30-second timeouts to prevent hanging on slow/unresponsive endpoints
• Proper error logging with context (URL included)
• Typed error handling that preserves the error message
• Appropriate error propagation to callers

Also applies to: 47-59

---

85-150: LGTM! Optimal parallel download with ordered processing.

The implementation correctly:

1. Downloads all images in parallel (line 105) for better performance
2. Processes them sequentially (line 108) to preserve page order in the PDF
3. Handles individual page failures gracefully without aborting the entire export (lines 95-102, 146-149)

This pattern balances performance and correctness.

---

117-128: Good format fallback for image embedding.

The try-catch cascade (PNG → JPEG) handles images where the actual format may not match the URL extension. This is practical for handling real-world data where content-type headers or file extensions may be incorrect.

---

301-308: LGTM! Proper XML entity escaping.

The escapeXml function correctly handles all five XML entities (&, <, >, ", '), preventing XML injection vulnerabilities when embedding user-provided episode titles in ComicInfo.xml metadata.

[coderabbitai]

⚠️ Potential issue | 🟠 Major

Refactor to avoid async Promise executor anti-pattern.

Using an async function as a Promise executor is problematic because:

1. Unhandled rejections in async code before the first await won't be caught by the Promise
2. Makes error handling inconsistent (some errors throw, some reject)
3. Static analysis tools flag this pattern as suspicious

Refactor to use a standard async function:

  async exportAsCBZ(options: ExportOptions): Promise<ExportResult> {
    const { episodeTitle, pages, includeAudio } = options;

-   return new Promise(async (resolve, reject) => {
-     try {
        // Create a temporary directory for the CBZ contents
        const tempDir = path.join(os.tmpdir(), `cbz_${Date.now()}_${Math.random().toString(36).slice(2)}`);
        fs.mkdirSync(tempDir, { recursive: true });

+       return new Promise<ExportResult>((resolve, reject) => {
        // CBZ is essentially a ZIP file containing images
        // Standard naming convention: page_001.png, page_002.png, etc.
        const archive = archiver('zip', {
          zlib: { level: 9 }, // Maximum compression
        });

        const chunks: Buffer[] = [];

        archive.on('data', (chunk: Buffer) => {
          chunks.push(chunk);
        });

        archive.on('end', () => {
          const buffer = Buffer.concat(chunks);
          const sanitizedTitle = this.sanitizeFilename(episodeTitle);
          const filename = `${sanitizedTitle}_manga.cbz`;

          // Clean up temp directory
          this.cleanupTempDir(tempDir);

          resolve({
            buffer,
            filename,
            mimeType: 'application/x-cbz',
            size: buffer.length,
          });
        });

        archive.on('error', (err: Error) => {
          this.cleanupTempDir(tempDir);
          reject(err);
        });

        // Add metadata file (ComicInfo.xml) for comic readers
        const comicInfo = this.generateComicInfoXml(episodeTitle, pages.length);
        archive.append(comicInfo, { name: 'ComicInfo.xml' });

        // Download and add each page image
-       for (const page of pages) {
+       (async () => {
+         try {
+           for (const page of pages) {
          if (!page.imageUrl) {
            console.warn(`Page ${page.pageNumber} has no image, skipping`);
            continue;
          }

          try {
            const imageBytes = await this.downloadImage(page.imageUrl);

            // Determine file extension from URL or content
            const ext = page.imageUrl.match(/\.(png|jpg|jpeg|webp)(\?|$)/i)?.[1] || 'png';
            const paddedNumber = String(page.pageNumber).padStart(3, '0');
            const imageName = `page_${paddedNumber}.${ext}`;

            archive.append(imageBytes, { name: imageName });
            console.log(`Added ${imageName} to CBZ`);
          } catch (error) {
            console.error(`Error adding page ${page.pageNumber} to CBZ:`, error);
            // Continue with next page
          }
-       }
+         }

        // Optionally include audio files
        if (includeAudio) {
          const audioDir = 'audio/';
          let hasAudio = false;

          for (const page of pages) {
            if (!page.audioUrl) continue;

            try {
              const audioBytes = await this.downloadAudio(page.audioUrl);
              const paddedNumber = String(page.pageNumber).padStart(3, '0');
              const audioName = `${audioDir}page_${paddedNumber}.mp3`;

              archive.append(audioBytes, { name: audioName });
              hasAudio = true;
              console.log(`Added ${audioName} to CBZ`);
            } catch (error) {
              console.error(`Error adding audio for page ${page.pageNumber}:`, error);
            }
          }

          // Add a README for audio files if any were included
          if (hasAudio) {
            const audioReadme = `Audio Files for ${episodeTitle}\n\nThis CBZ archive includes audiobook narration for each page.\nAudio files are located in the 'audio/' directory.\n\nFile naming: page_XXX.mp3 corresponds to page_XXX.png\n`;
            archive.append(audioReadme, { name: 'audio/README.txt' });
          }
        }

        // Finalize the archive
        archive.finalize();
-     } catch (error) {
-       reject(error);
-     }
+         } catch (error) {
+           this.cleanupTempDir(tempDir);
+           reject(error);
+         }
+       })();
    });
  }

🧰 Tools

🪛 Biome (2.1.2)

[error] 170-269: Promise executor functions should not be async.

(lint/suspicious/noAsyncPromiseExecutor)

🤖 Prompt for AI Agents

In backend/src/export/export.service.ts around lines 170 to 269, the code uses
an async function as the Promise executor (new Promise(async (resolve, reject)
=> { ... })), which is an anti-pattern; refactor by making the enclosing method
async and remove the new Promise wrapper: perform synchronous setup (tempDir,
archiver, chunks array), then create a small non-async Promise that listens to
archive 'end' and 'error' events (resolve with the buffer/metadata on 'end',
reject on 'error'), call archive.finalize(), await that Promise, and return the
result object; ensure try/catch/finally surrounds the await so tempDir cleanup
happens in finally and all errors are thrown (not implicitly unhandled) so
callers receive rejections consistently.

[coderabbitai]

⚠️ Potential issue | 🟠 Major

🧩 Analysis chain

QueueEvents wiring works; add error listener and tighten typing around optional fields

The QueueEvents setup and lifecycle logging for page and character queues are helpful for observability. Two improvements to consider:

• Attach an 'error' listener on each QueueEvents instance so issues in the BullMQ event stream (e.g., lost Redis connection) are surfaced clearly in logs rather than failing silently.
• Since pageQueueEvents/characterQueueEvents are declared as optional, either:
  • Make them non-optional once initialization succeeds, or
  • Guard before calling setupJobEventListeners
    to keep TypeScript happy and avoid any future refactors accidentally calling this helper with undefined.

Also applies to: 87-103

---

🌐 Web query:

In BullMQ v5.x, what events does `QueueEvents` emit (especially `error`), and are there recommended patterns for handling them in long-lived services?

💡 Result:

Short answer:

• QueueEvents emits the global queue events listed in the QueueEventsListener interface (examples: added, waiting, active, progress, completed, failed, delayed, stalled, removed, cleaned, drained, paused/resumed, duplicated/deduplicated/debounced, "retries-exhausted", "waiting-children", plus an error event and the low-level "ioredis:close"). See the API reference for the full list. [1][2]

• The QueueEvents "error" is a normal EventEmitter event (signature: error: (args: Error) => void). If you don't listen for errors on event emitters you risk unhandled exceptions bringing down your Node process. Attach an error handler to QueueEvents the same way you do for Workers. [2][3]

Recommended patterns for long‑lived services

• Always attach an error handler:

  • queueEvents.on('error', err => { /* log, alert, maybe restart */ });. This prevents unhandled exceptions. [2][3]

• Handle Redis connection lifecycle:

  • Use waitUntilReady()/run() or check the instance is ready before relying on events.
  • Listen for low-level connection events (e.g. "ioredis:close") and implement retries / reconnect/backoff. [4][2]

• Use resilient connection options:

  • Pass an explicit connection (mandatory in v5) with retry strategy / enableOfflineQueue as appropriate so the QueueEvents client can reconnect automatically. [3]

• Decide how to resume after interruptions:

  • If you must not miss historical events, use lastEventId: '0-0' (or store/restore the last event ID) to resume from a known stream position; otherwise start from the current stream to avoid replays. Use the QueueEvents option lastEventId carefully. [5][1]

• Monitor & self‑heal:

  • Log/emit alerts from the error handler; consider supervising QueueEvents (restart it on persistent failures) or run it under a process supervisor (systemd, k8s, pm2).
  • Combine QueueEvents with QueueScheduler/Workers and health checks so your service recovers cleanly. [3][6]

References

1. Events guide (examples, custom events).
2. QueueEventsListener / QueueEvents API reference (full event list, includes error and ioredis:close).
3. Workers guide (advice to attach error listeners; v5 connection requirement).
4. QueueEvents class docs (waitUntilReady/run/constructor).
5. Discussion / advice about lastEventId and replay semantics.

If you want, I can paste the exact event names (copied from the QueueEventsListener interface) and example code snippets for robust error/reconnect handling.

---

Now I need to check the actual code in the repository to verify the concerns:

---

🏁 Script executed:

```shell
#!/bin/bash
cat backend/src/queue/queue-events-bridge.service.ts

Length of output: 4962

---

Add missing error listener and fix optional typing inconsistency in QueueEvents setup

The code creates QueueEvents instances without attaching error listeners, which can cause unhandled exceptions to crash the service. Additionally, the fields are declared optional but used without guards in initialization (lines 65–67), while properly guarded in the destroy logic (lines 73–82)—creating a type-safety gap.

Required fixes:

• Attach an error listener in setupJobEventListeners() to handle connection failures and event stream errors (e.g., lost Redis connection).
• Either make the fields non-optional after successful initialization or guard both calls on lines 65–67 with null checks to maintain consistency with the destroy pattern.

Example error handler pattern (per BullMQ v5 guidance):

queueEvents.on('error', (err) => {
  this.logger.error(`[${type}] QueueEvents error:`, err);
});

Also applies to: 87–103 (destroy logic already correctly guards; ensure initialization follows the same pattern).

[coderabbitai]

⚠️ Potential issue | 🔴 Critical

🧩 Analysis chain

Verify model names for renderer providers.

The default model names may be incorrect or outdated:

• gemini-2.0-flash-exp suggests an experimental model that may not be stable for production
• gpt-image-1 doesn't match known OpenAI image generation models (typically dall-e-2 or dall-e-3)

Verify the correct model identifiers:

---

🌐 Web query:

What are the current image generation model names for Google Gemini and OpenAI DALL-E APIs?

💡 Result:

Short answer:

• Google (Gemini/Imagen): imagen-3.0-generate-002 (Imagen 3) and imagen-4.0-generate-001 / imagen-4.0-ultra-generate-001 (Imagen 4 variants); plus Gemini Flash image models (e.g., gemini-2.0-flash-preview-image-generation / nano‑banana / gemini-2.5-flash variants). [1][2][3]

• OpenAI (DALL·E / Images API): the current API image model is gpt-image-1 (newer GPT-native image model); older DALL·E names still appear (dall-e-3, dall-e-2) but gpt-image-1 is the primary image model in the API. [4][5]

Sources:

• Google Gemini / Imagen model docs. [1][2]
• Google developers forum (Nano Banana / Gemini Flash naming). [3]
• OpenAI / coverage of gpt-image-1 and Images API. [4][5]

---

Correct the Gemini model name; OpenAI model is valid.

The gpt-image-1 model is correct and is the primary OpenAI image generation API model, so no change needed there.

However, gemini-2.0-flash-exp appears to be incorrect. Current Gemini image generation models include gemini-2.0-flash-preview-image-generation and other Imagen variants, but no documented model uses the -exp suffix. Update line 117 to use a valid model identifier, such as gemini-2.0-flash-preview-image-generation or consult your Gemini API documentation for the correct model name if it differs.

🤖 Prompt for AI Agents

In backend/src/worker/generate.worker.ts around lines 117 to 118, the Gemini
model identifier is incorrect: replace 'gemini-2.0-flash-exp' with a valid
Gemini image-generation model name (e.g.,
'gemini-2.0-flash-preview-image-generation' or the correct identifier from your
Gemini API docs) while leaving the OpenAI default ('gpt-image-1') unchanged;
update the environment variable default so process.env.RENDERER_GEMINI_MODEL
falls back to the valid model string.

[coderabbitai]

⚠️ Potential issue | 🟠 Major

Database check contradicts optional database design.

The code throws an error if DATABASE_URL is not configured, but the worker's design (line 8 comment, line 48 conditional instantiation) explicitly supports running without a database. This prevents the worker from functioning in "database-optional" mode.

If the database is truly optional, consider one of these approaches:

• Allow jobs to proceed without persistence (ephemeral mode)
• Skip database operations gracefully and only emit events
• Or remove the "optional database" claim from documentation if persistence is actually required

Apply this diff to fail the job gracefully when database is unavailable:

-    if (!prisma) {
-      throw new Error('Database not configured - cannot retrieve episode data');
-    }
-
-    const episode = await prisma.episode.findUnique({
+    const episode = prisma ? await prisma.episode.findUnique({
       where: { id: episodeId },
       include: { characters: true },
-    });
+    }) : null;
 
     if (!episode) {
-      throw new Error(`Episode ${episodeId} not found`);
+      throw new Error(prisma ? `Episode ${episodeId} not found` : 'Database not configured');
     }

Committable suggestion skipped: line range outside the PR's diff.

🤖 Prompt for AI Agents

In backend/src/worker/generate.worker.ts around lines 304 to 306, the current
code throws an error when prisma (the database) is not configured which
contradicts the worker's documented "database-optional" design; instead, change
this branch to handle absence of the DB gracefully by not throwing: log a
warning about running in ephemeral/no-DB mode, skip any DB-specific retrievals
or persistence, and return/mark the job as handled (or emit the same events) so
the job can continue without persistence; ensure subsequent code paths check for
prisma before calling DB functions.

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

🧩 Analysis chain

Type assertion suggests Prisma schema mismatch.

Casting prisma to any to access the character model indicates the Character model is either missing from the Prisma schema or the client hasn't been regenerated after schema changes. This bypasses all type safety for character updates.

Verify that:

1. The Character model exists in backend/prisma/schema.prisma
2. Prisma client has been regenerated (npx prisma generate)
3. The Character model includes the imageUrl field

Run this script to check the schema:

---

🏁 Script executed:

#!/bin/bash
# Check if Character model exists in Prisma schema and has imageUrl field
rg -A 10 'model Character' backend/prisma/schema.prisma

Length of output: 344

---

---

🏁 Script executed:

#!/bin/bash
# Check if Prisma client types include Character model
fd -type f -name "*.d.ts" backend | xargs rg "character" -i -A 2 2>/dev/null || echo "No .d.ts files found"

# Also check the imports in the worker file
rg -B 5 -A 2 "import.*prisma" backend/src/worker/generate.worker.ts

Length of output: 97487

---

🏁 Script executed:

#!/bin/bash
# Check if Character is accessible in generated Prisma client
fd -type f -path "*node_modules/.prisma/client*" -name "index.d.ts" 2>/dev/null | head -1 | xargs rg "character:" 2>/dev/null | head -5

Length of output: 596

---

---

🏁 Script executed:

#!/bin/bash
# Check prisma import and initialization in worker file
rg -n -A 5 "import.*prisma" backend/src/worker/generate.worker.ts | head -20

# Also check if there's a prisma client file
fd -type f -name "client.ts" -o -name "index.ts" backend/src | grep -i prisma | head -5

Length of output: 500

---

🏁 Script executed:

#!/bin/bash
# Check the prisma setup/initialization in the worker
rg -n "const prisma|new PrismaClient" backend/src/worker/generate.worker.ts

Length of output: 64

---

---

🏁 Script executed:

#!/bin/bash
# Check the prisma variable type and context around line 442
rg -n -B 10 -A 3 'prisma as any.*character.update' backend/src/worker/generate.worker.ts

Length of output: 404

---

🏁 Script executed:

#!/bin/bash
# Check if prisma is properly typed or if there's a type issue
rg -n -B 2 'const prisma = DATABASE_URL' backend/src/worker/generate.worker.ts

Length of output: 130

---

Remove unnecessary any type assertion—Prisma client is properly typed.

The Character model exists in the schema with all required fields. The any cast on line 442 is unnecessary because:

• Character model is defined and properly included in the generated Prisma types
• PrismaClient is correctly initialized at line 48
• The if (prisma) check narrows the type from PrismaClient | undefined to PrismaClient, enabling direct access to typed methods

Change to:

if (prisma) {
  await prisma.character.update({
    where: { id: characterId },
    data: { imageUrl: result.imageUrl },
  });
}

This maintains type safety without needing schema regeneration or schema changes.

🤖 Prompt for AI Agents

In backend/src/worker/generate.worker.ts around lines 442 to 445, remove the
unnecessary `as any` type assertion on `prisma` and call the typed Prisma client
directly; wrap the update in the existing `if (prisma)` branch (or ensure
`prisma` is a `PrismaClient` before use) and call `await
prisma.character.update({ where: { id: characterId }, data: { imageUrl:
result.imageUrl } })` so the code uses the generated Prisma types instead of
casting to `any`.

[coderabbitai]

⚠️ Potential issue | 🟠 Major

Event types not defined in EventPayload union.

The worker emits character_done and character_failed events (lines 455, 469), but these types are not present in the EventPayload union type imported from events.service.ts. This will cause type errors in consumers expecting the defined EventPayload types.

Add the missing event types to the EventPayload union in backend/src/events/events.service.ts:

export type EventPayload =
  | { type: 'planning_started'; episodeId: string; message?: string }
  | { type: 'planning_progress'; episodeId: string; message?: string }
  | { type: 'planning_complete'; episodeId: string; message?: string }
  | { type: 'page_progress'; episodeId: string; page: number; pct: number }
  | { type: 'page_done'; episodeId: string; page: number; imageUrl: string; seed: number; version: number }
  | { type: 'page_failed'; episodeId: string; page: number; error: string }
  | { type: 'character_done'; episodeId: string; characterId: string; name: string; imageUrl: string }
  | { type: 'character_failed'; episodeId: string; characterId: string; name: string; error: string };

Also applies to: 463-469

🤖 Prompt for AI Agents

In backend/src/events/events.service.ts (add entries corresponding to worker
emits referenced around backend/src/worker/generate.worker.ts lines 449-455 and
463-469), the EventPayload union is missing the 'character_done' and
'character_failed' variants; update the EventPayload type to include | { type:
'character_done'; episodeId: string; characterId: string; name: string;
imageUrl: string } and | { type: 'character_failed'; episodeId: string;
characterId: string; name: string; error: string } so consumers accept the
worker-emitted events.

[coderabbitai]

Actionable comments posted: 2

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 85eb13e and 434c7c8.

📒 Files selected for processing (5)

• DOCUMENTATION.md (0 hunks)
• agent.md (1 hunks)
• implementation_status.md (0 hunks)
• public/words.md (0 hunks)
• warp.md (0 hunks)

💤 Files with no reviewable changes (4)

• public/words.md
• warp.md
• DOCUMENTATION.md
• implementation_status.md

🧰 Additional context used

🪛 markdownlint-cli2 (0.18.1)

agent.md

70-70: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

310-310: Bare URL used

(MD034, no-bare-urls)

---

380-380: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

534-534: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

605-605: Bare URL used

(MD034, no-bare-urls)

---

606-606: Bare URL used

(MD034, no-bare-urls)

---

790-790: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

847-847: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

1236-1236: Bare URL used

(MD034, no-bare-urls)

---

1237-1237: Bare URL used

(MD034, no-bare-urls)

---

1238-1238: Bare URL used

(MD034, no-bare-urls)

---

1239-1239: Bare URL used

(MD034, no-bare-urls)

---

1240-1240: Bare URL used

(MD034, no-bare-urls)

---

1241-1241: Bare URL used

(MD034, no-bare-urls)

---

1244-1244: Bare URL used

(MD034, no-bare-urls)

---

1245-1245: Bare URL used

(MD034, no-bare-urls)

---

1246-1246: Bare URL used

(MD034, no-bare-urls)

---

1249-1249: Bare URL used

(MD034, no-bare-urls)

---

1250-1250: Bare URL used

(MD034, no-bare-urls)

---

1251-1251: Bare URL used

(MD034, no-bare-urls)

🔇 Additional comments (2)

agent.md (2)

53-54: Verify AI model names against current API documentation.

The guide references specific AI model identifiers (e.g., gpt-5-mini, gpt-image-1, gemini-2.5-flash-image-preview, eleven_flash_v2_5) which may have changed or be inaccurate relative to current provider APIs. Confirm these model names are valid and currently available.

Lines affected: 53-54 (OpenAI/Gemini overview), 237-238 (OpenAI config), 244-245 (Gemini config).

Please search for and confirm:

1. Current OpenAI model names for planning and image generation
2. Current Gemini model names for planning and image generation
3. Current ElevenLabs TTS model name

Also applies to: 237-238, 244-245

---

1-1267: Guide is comprehensive and well-structured; good alignment with PR features.

The developer guide provides clear documentation of the new observability stack, queueing system, export functionality, and Prisma persistence. Architecture diagrams, request flows, API reference, and deployment instructions are well-presented and helpful for onboarding.

[coderabbitai]

🛠️ Refactor suggestion | 🟠 Major

Add language identifiers to fenced code blocks.

Several code blocks lack language specifications, which affects readability and syntax highlighting in rendered markdown. Apply language identifiers to all code blocks (e.g., ```sql, ```typescript, ```bash).

Affected lines: 70, 380, 534, 790, 847 (and potentially others).

Example fix for line 70:

-```
+```
 ┌─────────────────────────────────────────────────────────────┐

Also applies to: 380-380, 534-534, 790-790, 847-847

🧰 Tools

🪛 markdownlint-cli2 (0.18.1)

70-70: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

🤖 Prompt for AI Agents

In agent.md around lines 70, 380, 534, 790, and 847 (and other fenced blocks),
several fenced code blocks lack language identifiers; update each
triple-backtick fence to include the appropriate language tag (for example
```sql, ```typescript, ```bash, or ```text as appropriate) so rendered markdown
shows proper syntax highlighting, ensuring both opening and closing fences
remain and that the chosen language matches the code content.

[coderabbitai]

🛠️ Refactor suggestion | 🟠 Major

Wrap bare URLs in markdown link syntax.

Several URLs are listed as bare text instead of proper markdown links, which reduces usability. Wrap URLs with [text](url) syntax for consistent documentation rendering.

Affected lines: 310, 605-606, 1236-1251.

Example fix:

-1. Create project at https://supabase.com
+1. Create project at [Supabase](https://supabase.com)

-**Sentry**: https://sentry.io (errors, performance, session replay)
-**Jaeger**: http://localhost:16686 (distributed traces)
+**Sentry**: [https://sentry.io](https://sentry.io) (errors, performance, session replay)
+**Jaeger**: [http://localhost:16686](http://localhost:16686) (distributed traces)

Also applies to: 605-606, 1236-1251

🧰 Tools

🪛 markdownlint-cli2 (0.18.1)

310-310: Bare URL used

(MD034, no-bare-urls)

🤖 Prompt for AI Agents

In agent.md around lines 310, 605-606, and 1236-1251, several bare URLs are
present; replace each bare URL with markdown link syntax [text](url). For each
URL choose concise, descriptive link text (e.g., "Supabase" for
https://supabase.com or the page title), update all occurrences at the listed
line ranges to the [label](https://...) format, and ensure spacing and
punctuation around the new links are preserved for consistent rendering across
the document.

[coderabbitai]

Actionable comments posted: 17

🧹 Nitpick comments (16)

COLLABORATION_QUICK_REFERENCE.md (2)

1-482: Strong quick-reference structure with practical patterns.

This quick-reference guide effectively distills collaboration implementation into actionable decisions and patterns. The decision matrices, code templates, and common pitfalls sections provide valuable guidance for developers implementing real-time features. The separation of state sync from presence updates (visible in templates and schemas) aligns well with the queueing and observability infrastructure being added in this PR.

Suggested optional refinement: Consider adding a "When to Use" section near line 60 that explicitly maps decision matrix outcomes to specific use cases (e.g., "Choose custom hybrid + WebSocket if: , , "). This would further accelerate decision-making for new developers.

---

416-478: Observability tie-in opportunity.

The "Performance Tips" and "Monitoring Checklist" sections (lines 416–456) define metrics to track (sync latency p50/p95/p99, message throughput, conflict frequency, etc.). Consider cross-referencing the observability infrastructure added in this PR (Sentry, OpenTelemetry, structured logging) so implementers know how to instrument these metrics within the new observability stack.

COLLABORATION_ARCHITECTURE.md (2)

317-581: Tool analysis section is thorough but could be deferred.

Lines 317–581 (Analysis of Collaboration Tools) provide detailed deep-dives into Figma, tldraw, Excalidraw, and Miro with architecture code examples. While valuable, this level of detail may be better suited to a separate technical research doc or wiki, leaving this document focused on actionable recommendations for MangaFusion. Current PR doesn't require these tools as dependencies; they're purely reference material.

Consider distilling this section to a 50–100 line summary table (tool name, core approach, key trade-offs, suitable-for) and linking to detailed analysis in a companion doc or reference section.

---

821-873: Architecture diagram and tech choices are well-justified.

The recommended architecture for MangaFusion (lines 821–873) clearly separates state sync from presence tracking, leverages the queue infrastructure being added in this PR, and proposes sensible technology choices (WebSocket + Socket.IO, custom hybrid sync, server-as-source-of-truth). The ASCII diagram effectively communicates the frontend/backend/storage layers.

Note: The diagram suggests MongoDB/PostgreSQL at line 866. The PR adds Prisma with PostgreSQL schema changes (per AI summary). Consider updating line 866 to reference "PostgreSQL (via Prisma ORM)" for alignment with current PR infrastructure.

AI_SKETCH_REFINEMENT_WORKFLOWS.md (2)

1748-1811: Good optimization strategies for refinement caching and batch processing.

Hash-based cache keys and Promise.allSettled for fault tolerance are solid patterns. Consider making batchSize configurable to adapt to different API rate limits.

-    const batchSize = 5; // Adjust based on API limits
+    const batchSize = options.batchSize ?? 5; // Configurable, defaults to 5

---

1967-1992: Comprehensive and current references.

The mix of official API documentation, academic papers, and community resources is appropriate for a technical implementation guide. Consider adding link validation to your CI/CD pipeline to catch any broken references.

CANVAS_RESEARCH_COMPILATION.md (1)

81-81: Fix redundant acronym reference.

Line 81 contains "PNG images" where "PNGs" is more concise (PNG already stands for "Portable Network Graphics", so adding "images" is redundant). Consider: "Extract layers as PNGs".

This is a minor grammar improvement for documentation clarity.

CANVAS_LIBRARIES_COMPARISON.md (2)

26-26: Consider alternative wording to reduce reliance on intensifiers like "very".

Lines 26 and 29 use "Very easy" and "Very large" multiple times. Consider:

• "Very easy" → "Straightforward" or "Minimal learning curve"
• "Very large" → "Extensive" or "Major" community

This improves documentation clarity and readability.

Also applies to: 29-29

---

143-143: Apply consistent hyphenation for compound modifiers.

Line 143: "280+ open source contributors" should be "280+ open-source contributors" for proper grammar.

ACCESSIBILITY_RESEARCH_INDEX.md (2)

424-443: Wrap bare URLs in markdown link format.

Lines 424-443 list external resources as bare URLs, which violates markdown best practices (MD034). Wrap these in markdown link syntax for consistency and better rendering.

-**W3C WCAG 2.1:** https://www.w3.org/WAI/WCAG21/quickref/
+**W3C WCAG 2.1:** [https://www.w3.org/WAI/WCAG21/quickref/](https://www.w3.org/WAI/WCAG21/quickref/)

Apply similarly to all URLs in this section (lines 424-443).

---

495-495: Use proper heading syntax instead of emphasis.

Line 495 uses **End of Index** as emphasis, but this appears to be a document boundary marker. Either use a proper heading (## End of Index) or remove the emphasis formatting.

CANVAS_ANALYSIS_INDEX.md (1)

46-46: Specify language for fenced code blocks.

Five code blocks lack language identifiers (MD040). While these appear to be ASCII diagrams rather than executable code, adding language specs improves documentation rendering:

-```
+```text
[ASCII diagram here]
-```
+```

Apply to lines 46, 183, 266, 306, and 317. Use `text` for ASCII diagrams or `plaintext`.

Also applies to: 183-183, 266-266, 306-306, 317-317

ACCESSIBILITY_TOOLS_COMPARISON.md (1)

424-443: Wrap bare URLs in markdown link format for consistency.

Similar to other documentation files, bare URLs in the resources section (lines 424-443) should be wrapped per markdown conventions.

ACCESSIBILITY_DRAWING_APPS_RESEARCH.md (1)

424-443: Wrap bare URLs in markdown link format.

Multiple sections contain bare URLs that should be wrapped per markdown conventions (MD034). Apply similar fix to the references section as suggested in other documentation files.

Also applies to: 1510-1562

CANVAS_FEATURE_INTEGRATION.md (2)

35-35: Add language identifiers to all fenced code blocks.

Multiple code fences are missing language specifiers, which impacts documentation rendering and syntax highlighting. All fenced code blocks should include a language identifier (e.g., ```typescript, ```sql, ```bash).

Affected lines: 35 (ASCII diagram), 210 (data flow), 391 (canvas use cases), 539 (operation flow diagram), 565 (database schema), 845 (TypeScript options), 922 (bash curl examples).

For example:

- ```
+ ```
  ┌────────────────────────────────────────────────────────────────────┐
  │                        FRONTEND LAYER (Next.js:3000)              │

For TypeScript and SQL sections, use the appropriate language identifiers:

• TypeScript code: ```typescript
• SQL schemas: ```sql
• Bash commands: ```bash
• ASCII diagrams: ` ```
• Plain text/data flows: ` ```

Also applies to: 210-210, 391-391, 539-539, 565-565, 845-845, 922-922

---

200-210: Convert emphasis-as-headings to proper markdown heading syntax.

Several section labels use bold emphasis (**Label:**) instead of proper heading levels. For consistency and better markdown parsing, these should be converted to heading syntax using ### or ####.

Examples to refactor:

• Line 203: **Data Flow:** → ### Data Flow
• Line 354: **Persistence Points:** → ### Persistence Points
• Line 539: **Events:** → ### Events
• Line 551: **Canvas Operation Flow** → ### Canvas Operation Flow

This improves document structure and enables proper table-of-contents generation.

Also applies to: 340-380, 490-510, 530-565

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 434c7c8 and f5f209f.

⛔ Files ignored due to path filters (1)

• package-lock.json is excluded by !**/package-lock.json

📒 Files selected for processing (23)

• ACCESSIBILITY_CODE_EXAMPLES.md (1 hunks)
• ACCESSIBILITY_DRAWING_APPS_RESEARCH.md (1 hunks)
• ACCESSIBILITY_IMPLEMENTATION_CHECKLIST.md (1 hunks)
• ACCESSIBILITY_RESEARCH_INDEX.md (1 hunks)
• ACCESSIBILITY_TOOLS_COMPARISON.md (1 hunks)
• AI_SKETCH_REFINEMENT_WORKFLOWS.md (1 hunks)
• BENCHMARK_ANALYSIS.md (1 hunks)
• CANVAS_ANALYSIS_INDEX.md (1 hunks)
• CANVAS_EXPLORATION_SUMMARY.md (1 hunks)
• CANVAS_FEATURE_INTEGRATION.md (1 hunks)
• CANVAS_FEATURE_README.md (1 hunks)
• CANVAS_INTEGRATION_ARCHITECTURE.txt (1 hunks)
• CANVAS_INTEGRATION_QUICK_START.md (1 hunks)
• CANVAS_LIBRARIES_COMPARISON.md (1 hunks)
• CANVAS_PERFORMANCE_OPTIMIZATION_GUIDE.md (1 hunks)
• CANVAS_RESEARCH_COMPILATION.md (1 hunks)
• CANVAS_STORAGE_IMPLEMENTATION.md (1 hunks)
• CANVAS_STORAGE_INDEX.md (1 hunks)
• CANVAS_STORAGE_QUICK_START.md (1 hunks)
• CANVAS_STORAGE_RESEARCH.md (1 hunks)
• COLLABORATION_ARCHITECTURE.md (1 hunks)
• COLLABORATION_QUICK_REFERENCE.md (1 hunks)
• COLLABORATION_RESEARCH_SUMMARY.md (1 hunks)

✅ Files skipped from review due to trivial changes (2)

• COLLABORATION_RESEARCH_SUMMARY.md
• CANVAS_PERFORMANCE_OPTIMIZATION_GUIDE.md

🧰 Additional context used

🪛 LanguageTool

CANVAS_INTEGRATION_ARCHITECTURE.txt

[grammar] ~147-~147: Ensure spelling is correct
Context: ... │ │ 2. Get current page imageUrl ...

(QB_NEW_EN_ORTHOGRAPHY_ERROR_IDS_1)

CANVAS_RESEARCH_COMPILATION.md

[style] ~81-~81: This phrase is redundant (‘G’ stands for ‘graphic’). Use simply “PNGs”.
Context: ...on + kra-py library - Extract layers as PNG images - Import into web editor for refinement...

(ACRONYM_TAUTOLOGY)

COLLABORATION_ARCHITECTURE.md

[style] ~311-~311: It’s more common nowadays to write this noun as one word.
Context: ...s need sync) - Color-coded cursors with user names improve UX - Throttling prevents networ...

(RECOMMENDED_COMPOUNDS)

---

[style] ~386-~386: Consider a different adjective to strengthen your wording.
Context: ...y**: HIGH (custom solution requires deep understanding) --- ### 2. tldraw (Pro...

(DEEP_PROFOUND)

---

[style] ~1072-~1072: To elevate your writing, try using a synonym here.
Context: ...IUM | 4-6 days | HIGH | Race conditions hard to test | ### Complexity Score Breakdo...

(HARD_TO)

ACCESSIBILITY_DRAWING_APPS_RESEARCH.md

[uncategorized] ~415-~415: If this is a compound adjective that modifies the following noun, use a hyphen.
Context: ...Accessible 1. Toolbar & Controls - Full screen reader support 2. Menus & Dialogs -...

(EN_COMPOUND_ADJECTIVE_INTERNAL)

---

[style] ~1683-~1683: To elevate your writing, try using a synonym here.
Context: ... Contrast Problem: Text or graphics hard to read Solution: ```typescript co...

(HARD_TO)

ACCESSIBILITY_TOOLS_COMPARISON.md

[grammar] ~278-~278: Use a hyphen to join words.
Context: ...sibility #### Issues - No explicit high contrast CSS - Colors not tested in high...

(QB_NEW_EN_HYPHEN)

---

[style] ~507-~507: In American English, abbreviations like “etc.” require a period.
Context: ...-------------| | Select tool | ✓ (R, C, etc) | ✓ (R, C, etc) | ⚠️ Menu-based | | Dr...

(ETC_PERIOD)

---

[style] ~507-~507: In American English, abbreviations like “etc.” require a period.
Context: ... Select tool | ✓ (R, C, etc) | ✓ (R, C, etc) | ⚠️ Menu-based | | Draw shape | ✓ (Co...

(ETC_PERIOD)

---

[grammar] ~643-~643: Use a hyphen to join words.
Context: ...hensive keyboard support - Explicit high contrast CSS - Better screen reader anno...

(QB_NEW_EN_HYPHEN)

CANVAS_ANALYSIS_INDEX.md

[style] ~431-~431: Some style guides suggest that commas should set off the year in a month-day-year date.
Context: ...nance - Last Updated: November 17, 2025 - Status: Ready for implementation ...

(MISSING_COMMA_AFTER_YEAR)

CANVAS_LIBRARIES_COMPARISON.md

[style] ~26-~26: As an alternative to the over-used intensifier ‘very’, consider replacing this phrase.
Context: ...Moderate | Easy | Steep (vector math) | Very easy | Moderate | | Mobile/Touch | Good ...

(EN_WEAK_ADJECTIVE)

---

[style] ~29-~29: As an alternative to the over-used intensifier ‘very’, consider replacing this phrase.
Context: ...Pointer Events | | Community Size | Very large | Large | Small/declining | Very large ...

(EN_WEAK_ADJECTIVE)

---

[style] ~29-~29: As an alternative to the over-used intensifier ‘very’, consider replacing this phrase.
Context: ... Very large | Large | Small/declining | Very large | Large | | Last Major Release | 20...

(EN_WEAK_ADJECTIVE)

---

[grammar] ~143-~143: Use a hyphen to join words.
Context: ...eScript migration ongoing) - 280+ open source contributors - 400+ open issues...

(QB_NEW_EN_HYPHEN)

CANVAS_STORAGE_IMPLEMENTATION.md

[grammar] ~1134-~1134: Ensure spelling is correct
Context: ...ith compression) - Large file save: 100-300ms (with Supabase upload) - Size reduction...

(QB_NEW_EN_ORTHOGRAPHY_ERROR_IDS_1)

CANVAS_STORAGE_INDEX.md

[style] ~15-~15: Consider a different adjective to strengthen your wording.
Context: ...CANVAS_STORAGE_RESEARCH.md Purpose: Deep research into storage strategies **Leng...

(DEEP_PROFOUND)

COLLABORATION_QUICK_REFERENCE.md

[style] ~80-~80: Consider using a different verb to strengthen your wording.
Context: ...dates - [ ] Add user color coding - [ ] Create selection awareness - [ ] Handle user j...

(CREATE_AWARENESS)

🪛 markdownlint-cli2 (0.18.1)

ACCESSIBILITY_IMPLEMENTATION_CHECKLIST.md

10-10: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

90-90: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

210-210: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

249-249: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

316-316: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

343-343: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

398-398: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

509-509: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

CANVAS_FEATURE_INTEGRATION.md

35-35: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

203-203: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

210-210: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

354-354: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

360-360: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

366-366: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

391-391: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

539-539: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

551-551: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

565-565: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

CANVAS_STORAGE_QUICK_START.md

730-730: Bare URL used

(MD034, no-bare-urls)

---

731-731: Bare URL used

(MD034, no-bare-urls)

---

732-732: Bare URL used

(MD034, no-bare-urls)

---

733-733: Bare URL used

(MD034, no-bare-urls)

---

734-734: Bare URL used

(MD034, no-bare-urls)

ACCESSIBILITY_DRAWING_APPS_RESEARCH.md

424-424: Bare URL used

(MD034, no-bare-urls)

---

425-425: Bare URL used

(MD034, no-bare-urls)

---

426-426: Bare URL used

(MD034, no-bare-urls)

---

429-429: Bare URL used

(MD034, no-bare-urls)

---

430-430: Bare URL used

(MD034, no-bare-urls)

---

431-431: Bare URL used

(MD034, no-bare-urls)

---

434-434: Bare URL used

(MD034, no-bare-urls)

---

435-435: Bare URL used

(MD034, no-bare-urls)

---

436-436: Bare URL used

(MD034, no-bare-urls)

---

437-437: Bare URL used

(MD034, no-bare-urls)

---

441-441: Bare URL used

(MD034, no-bare-urls)

---

443-443: Bare URL used

(MD034, no-bare-urls)

---

495-495: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

CANVAS_FEATURE_README.md

35-35: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

203-203: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

210-210: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

ACCESSIBILITY_TOOLS_COMPARISON.md

424-424: Bare URL used

(MD034, no-bare-urls)

---

425-425: Bare URL used

(MD034, no-bare-urls)

---

426-426: Bare URL used

(MD034, no-bare-urls)

---

429-429: Bare URL used

(MD034, no-bare-urls)

---

430-430: Bare URL used

(MD034, no-bare-urls)

---

431-431: Bare URL used

(MD034, no-bare-urls)

---

434-434: Bare URL used

(MD034, no-bare-urls)

---

435-435: Bare URL used

(MD034, no-bare-urls)

---

436-436: Bare URL used

(MD034, no-bare-urls)

---

437-437: Bare URL used

(MD034, no-bare-urls)

---

441-441: Bare URL used

(MD034, no-bare-urls)

---

443-443: Bare URL used

(MD034, no-bare-urls)

---

495-495: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

CANVAS_ANALYSIS_INDEX.md

46-46: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

183-183: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

266-266: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

306-306: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

317-317: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

ACCESSIBILITY_RESEARCH_INDEX.md

424-424: Bare URL used

(MD034, no-bare-urls)

---

425-425: Bare URL used

(MD034, no-bare-urls)

---

426-426: Bare URL used

(MD034, no-bare-urls)

---

429-429: Bare URL used

(MD034, no-bare-urls)

---

430-430: Bare URL used

(MD034, no-bare-urls)

---

431-431: Bare URL used

(MD034, no-bare-urls)

---

434-434: Bare URL used

(MD034, no-bare-urls)

---

435-435: Bare URL used

(MD034, no-bare-urls)

---

436-436: Bare URL used

(MD034, no-bare-urls)

---

437-437: Bare URL used

(MD034, no-bare-urls)

---

441-441: Bare URL used

(MD034, no-bare-urls)

---

443-443: Bare URL used

(MD034, no-bare-urls)

---

495-495: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

AI_SKETCH_REFINEMENT_WORKFLOWS.md

48-48: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

135-135: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

215-215: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

1712-1712: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

1724-1724: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

1918-1918: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

1925-1925: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

1932-1932: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

1939-1939: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

1946-1946: Emphasis used instead of a heading

(MD036, no-emphasis-as-heading)

---

1955-1955: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

CANVAS_LIBRARIES_COMPARISON.md

25-25: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

44-44: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

146-146: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

191-191: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

205-205: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

218-218: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

234-234: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

265-265: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

280-280: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

295-295: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

313-313: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

322-322: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

333-333: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

342-342: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

355-355: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

362-362: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

373-373: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

381-381: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

394-394: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

407-407: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

443-443: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

CANVAS_STORAGE_INDEX.md

199-199: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

297-297: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

321-321: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

413-413: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

425-425: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

442-442: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

452-452: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

---

496-496: Bare URL used

(MD034, no-bare-urls)

---

497-497: Bare URL used

(MD034, no-bare-urls)

---

498-498: Bare URL used

(MD034, no-bare-urls)

---

499-499: Bare URL used

(MD034, no-bare-urls)

---

502-502: Bare URL used

(MD034, no-bare-urls)

---

529-529: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

COLLABORATION_QUICK_REFERENCE.md

37-37: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

🔇 Additional comments (21)

BENCHMARK_ANALYSIS.md (1)

1-40: Establish sources and citations for benchmark data.

The document provides specific performance metrics (e.g., "Canvas to JPEG blob: 30-50ms," ImageBitmap creation "10-20ms"). These benchmarks lack citations or methodology notes. Are these derived from published research (Excalidraw/tldraw repos, performance APIs), internal testing, or estimates?

To strengthen credibility, either:

• Link to source repositories or published benchmarks (e.g., Excalidraw's renderer.tsx performance tests)
• Document the testing methodology used (browser versions, device specs, test harness)
• Clearly label extrapolated estimates vs. empirically verified measurements

For example:

- Canvas to JPEG blob | 30-50ms | All | Quality 0.85
+ Canvas to JPEG blob | 30-50ms | All | Quality 0.85 [*empirically measured on Chrome 120, 2021 MacBook Pro]

COLLABORATION_ARCHITECTURE.md (1)

1131-1219: Excellent pragmatic recommendations for MangaFusion.

The "Recommendations for MangaFusion" section clearly aligns with current PR priorities: document-first approach, phased implementation, and explicit NOT recommended guidance (CRDTs, WebRTC, custom OT, multi-server setup). The recommendation to start with WebSocket + basic sync + last-writer-wins is pragmatic and well-justified. Integration points with existing code (lines 1174–1217) directly tie to the queue/observability infrastructure being added.

Strong point: Acknowledgment that "Current implementation does not include multiplayer collaboration" (line 1232) keeps scope clear and future-focused.

AI_SKETCH_REFINEMENT_WORKFLOWS.md (7)

284-325: Good provider selection strategy.

The fallback logic and scenario-based routing (fast/budget-conscious, balanced, quality-focused) aligns well with the PR's multi-provider approach and provides clear decision paths for different use cases.

---

874-1037: Well-designed style consistency framework.

The multi-method approach (guide analysis, character reference extraction, consistency validation) provides a solid foundation for maintaining visual coherence across pages. The use of Gemini Vision for semantic analysis is appropriate and aligns with the PR's AI strategy.

---

1103-1259: Excellent manga-specific prompt engineering utilities.

The prompt builder provides comprehensive style templates, quality tiers, and LoRA integration. The examples span multiple manga genres and demonstrate professional-grade prompt crafting. This is well-suited for the refinement workflow.

---

1297-1385: Solid API endpoint design.

The RefinementController provides clear request/response contracts and appropriate error handling. Endpoint naming (/api/refine/sketch, /api/refine/inpaint) is intuitive and aligned with the PR's architecture.

---

1500-1519: Correct NestJS module integration pattern.

The module import follows standard NestJS composition and fits well with the existing architecture described in the PR.

---

1580-1639: Well-designed schema for refinement tracking.

The RefinementVersion and InpaintOperation models properly capture refinement history with metadata, enabling rollback and A/B testing capabilities. Cascade deletes maintain referential integrity.

---

1815-1910: Solid QA framework with clear scoring criteria.

The multi-dimensional scoring (structure, manga quality, artifacts, consistency) with weighted thresholds provides a good foundation for automated quality gates. Note that placeholder implementations (marked // Placeholder) will need integration with actual image analysis libraries or vision APIs.

Verify that the actual implementation (outside this document) will include real image analysis for checkStructureMatch, checkMangaCharacteristics, and checkForArtifacts, likely using OpenCV, TensorFlow, or cloud vision APIs.

CANVAS_FEATURE_README.md (1)

290-296: Cross-reference research documentation consistently.

The "Research Documentation" section references research files but should verify these match the actual file names provided elsewhere in the PR (e.g., CANVAS_STORAGE_RESEARCH.md, CANVAS_RESEARCH_COMPILATION.md). Ensure all referenced documents exist and are accessible from the repository structure.

CANVAS_RESEARCH_COMPILATION.md (1)

1-50: Verify alignment between research recommendations and actual implementation documents.

This compilation references extensive research across 20 agents and recommends specific choices (Fabric.js, Segmind, PostgreSQL+Supabase hybrid storage). Ensure the implementation-focused documents (CANVAS_STORAGE_IMPLEMENTATION.md, CANVAS_FEATURE_README.md, etc.) consistently follow these recommendations.

CANVAS_STORAGE_INDEX.md (1)

1-50: Document is well-organized and provides excellent navigation guidance.

The index file successfully provides multiple reading paths (Project Managers, Architects, Backend Developers, Frontend Developers) with realistic time estimates. The document map at the end clearly shows the relationship between all four main documents. This is a good reference implementation for documentation navigation.

ACCESSIBILITY_RESEARCH_INDEX.md (1)

1-495: Comprehensive accessibility research index—well structured and valuable.

The document provides an excellent navigation framework for the four companion accessibility documents. Cross-references are clear, success criteria are measurable, and the role-based guidance (designers, developers, QA, PMs) is practical. Structure with quick-start paths, WCAG mappings, and tool recommendations will help teams implement accessibility effectively.

CANVAS_INTEGRATION_ARCHITECTURE.txt (1)

1-607: Excellent architecture documentation with clear visual workflows.

The diagrams effectively contrast current vs. proposed architecture, the CanvasService methods are well-documented with step-by-step breakdowns, and the database schema changes are comprehensive with proper indexing. Request/response examples with realistic data make the API contract clear. The phased timeline with checklists provides actionable implementation guidance.

CANVAS_STORAGE_RESEARCH.md (1)

1-1290: Comprehensive storage architecture research with practical implementation paths.

The document systematically explores serialization formats (JSON, binary, hybrid), compression techniques (delta, RLE, GZIP, point reduction), and save strategies. The database schema options (PostgreSQL JSONB, Supabase + DB, hybrid) are well-analyzed with pros/cons. Phased implementation recommendations and cost estimation ($1/month for typical usage) make this actionable. Code examples and benchmarks support decision-making effectively.

CANVAS_INTEGRATION_QUICK_START.md (1)

1-400: Effective quick-start guide with clear phase breakdown and design rationale.

The executive summary efficiently captures architecture, integration points, and phases. Design decisions (Canvas as separate entity, stroke serialization, image compositing, optional per-page) are well-justified. Example API calls and schema summaries provide concrete reference points. The week-by-week rollout plan with clear MVP→Extended→Production progression helps with planning.

CANVAS_ANALYSIS_INDEX.md (1)

1-457: Clear navigation index bridging Canvas feature documentation suite.

The index effectively cross-references the four companion documents (Feature Integration, Quick Start, Architecture, Exploration Summary) and provides quick-lookup tables for readers at different levels (Executives, Architects, Developers). Success criteria, risk mitigation, and tech stack recommendations are concisely summarized. File organization section clearly shows how all documents relate.

ACCESSIBILITY_TOOLS_COMPARISON.md (1)

1-661: Thorough accessibility comparison providing actionable recommendations.

The side-by-side analysis of Figma, Excalidraw, and Google Drawings is comprehensive and fair, with clear ratings for each accessibility dimension. Strengths and critical limitations (e.g., "Cannot draw shapes using keyboard alone" in Excalidraw) are well-documented with GitHub issue references. Assessment tables and use-case recommendations (accessibility-first → Figma, quick diagramming → Excalidraw, Google integration → Google Drawings) provide practical guidance. Known issues and improvement paths are valuable for teams considering each tool.

ACCESSIBILITY_DRAWING_APPS_RESEARCH.md (1)

1-1792: Comprehensive accessibility implementation guide—excellent reference for drawing apps.

The 13-part structure methodically covers keyboard navigation (with 20+ essential shortcuts), screen reader strategies (ARIA implementation, canvas fallbacks, live regions), high contrast mode detection and CSS, colorblind-friendly palettes (blue/orange base, pattern textures), and zoom accessibility. The WCAG criterion-by-criterion breakdown (Part 2, 12-13) maps abstract standards to concrete drawing-app scenarios. Code examples in HTML/TypeScript and testing checklists throughout make this immediately actionable. Common pitfalls section (Part 11) captures real issues teams encounter.

Readability note: At 1,792 lines, this is a reference tome rather than a learning document. The table of contents helps navigation, but consider whether team members will discover relevant sections or need section-specific quick guides.

CANVAS_EXPLORATION_SUMMARY.md (1)

1-380: Effective executive summary setting context for Canvas feature integration.

The document successfully bridges stakeholders and detailed documentation, with clear phase breakdown (4 phases, 44-60 hours total), integration points across database/API/service/frontend/storage layers, and tech stack recommendations. The architecture diagrams show current vs. proposed workflow. Estimated effort enables realistic planning (2-3 weeks full-time, 4-6 weeks half-time). Inclusion of dependencies, prerequisites, and open questions facilitates kickoff discussions.

CANVAS_FEATURE_INTEGRATION.md (1)

1-50: LGTM — Well-structured canvas feature integration plan.

The document provides a comprehensive and well-organized integration plan that aligns clearly with the backend systems introduced in this PR (Prisma schema, QueueService, ExportService, ObservabilityModule, StorageService). The architecture diagrams, workflows, database schema changes, API endpoints, and implementation roadmap are detailed and coherent. The integration points table (section 13) clearly maps dependencies to the existing infrastructure. The risk assessment is thoughtful, and the estimated effort (~1 week) appears reasonable for a feature of this scope.

[coderabbitai]

🛠️ Refactor suggestion | 🟠 Major

Systematically add language identifiers to all fenced code blocks.

This file contains 25+ code blocks (HTML, CSS, TypeScript) without language specifications. Examples: lines 9 (HTML), 52 (CSS), 111 (TypeScript), 173 (HTML), 327 (CSS), 487 (TypeScript), etc.

Impact: Missing identifiers affect syntax highlighting, accessibility for screen readers, and documentation rendering quality. This pattern appears across multiple documentation files in the PR.

Recommendation: Use a find-replace or script to systematically add language identifiers:

• html for HTML snippets
• css for CSS snippets
• typescript for TypeScript snippets

Also applies to: 52-107, 111-167, 124-139, 173-323, 327-485, 487-653, 661-822, 825-964, 966-1026, 1038-1090, 1210-1435, 1322-1435

🤖 Prompt for AI Agents

In ACCESSIBILITY_CODE_EXAMPLES.md around lines 9 to 48 (and across the other
ranges listed), the fenced code blocks are missing language identifiers; update
each triple-backtick fence to include the appropriate language (e.g., ```html,
```css, ```typescript) so syntax highlighting and rendering work correctly.
Systematically scan the file (or run a script) to replace all opening fences
with the correct language tag for each snippet category (HTML snippets like the
canvas example -> ```html, CSS snippets -> ```css, TypeScript snippets ->
```typescript), ensuring every fenced block in the ranges provided is updated
and preserved exactly otherwise.

[coderabbitai]

🛠️ Refactor suggestion | 🟠 Major

Add language specifications to fenced code blocks for proper syntax highlighting.

Multiple code blocks are missing language identifiers (e.g., css, html, typescript). This affects both documentation rendering and accessibility for screen readers. The linter flagged 10 instances across the file.

Example fix:

-```
+```css
 /* Must have visible focus for all interactive elements */
 button:focus-visible,

This should be applied to all code blocks to ensure consistent formatting and proper code highlighting.

Also applies to: 89-107, 124-139, 149-174, 272-309, 512-521

🧰 Tools

🪛 markdownlint-cli2 (0.18.1)

90-90: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

🤖 Prompt for AI Agents

In ACCESSIBILITY_IMPLEMENTATION_CHECKLIST.md around lines 76-95 (and also at the
other flagged ranges 89-107, 124-139, 149-174, 272-309, 512-521), several fenced
code blocks are missing language identifiers; update each fenced block opening
(``` ) to include the correct language tag (e.g., ```css, ```html,
```typescript) that matches the snippet so the renderer and screen readers can
provide proper syntax highlighting and accessibility; ensure you apply this
consistently to every fenced block in those ranges and run the linter to verify
no missing language identifiers remain.

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

Add language identifier to ASCII diagram fences.

Lines 48, 135, 215, 1712, 1724, and 1955 have fenced code blocks without language specifications. Per markdownlint (MD040), all fenced code blocks should declare their language.

For ASCII diagrams and plain-text boxes, use the language identifier text or remove the fence and use indentation instead.

Suggested fix: Add language identifier to all affected code blocks:

-```
+```text
 ┌─────────────────────────────────────────────────────────────┐
 │ SKETCH-TO-MANGA REFINEMENT USER FLOW                       │

Apply the same pattern to lines 135–211, 215–265, 1712–1744, and 1955–1963.

🧰 Tools

🪛 markdownlint-cli2 (0.18.1)

48-48: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

🤖 Prompt for AI Agents

In AI_SKETCH_REFINEMENT_WORKFLOWS.md around the fenced blocks at lines 48–83,
135–211, 215–265, 1712–1744, 1724 (inside that range), and 1955–1963, the ASCII
diagram/code fences are missing a language identifier which violates MD040; for
each fenced block either add the language tag ```text on the opening fence (and
keep the closing fence) or remove the fence and convert the block to indented
plain text, ensuring all previously fenced diagrams now declare a language to
satisfy markdownlint.

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

Fix typo in variable name; verify storage dependency injection.

Line 394 has a typo: imageBas64 should be imageBase64. Additionally, the constructor references this.storageService but the constructor isn't shown — ensure this dependency is properly injected in the full implementation.

-      const imageBas64 = response.data.images[0];
-      const imageBuffer = Buffer.from(imageBas64, 'base64');
+      const imageBase64 = response.data.images[0];
+      const imageBuffer = Buffer.from(imageBase64, 'base64');

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	```typescript
	// backend/src/refinement/segmind.service.ts
	import axios from 'axios';
	interface SketchRefinementRequest {
	sketchImage: string; // Base64 PNG
	prompt: string;
	guidanceScale?: number;
	controlStrength?: number;
	numOutputs?: number;
	}
	@Injectable()
	export class SegmindRefinementService {
	private readonly apiKey = process.env.SEGMIND_API_KEY;
	private readonly baseUrl = 'https://api.segmind.com/v1';
	/**
	* Refine sketch using Segmind ControlNet SDXL
	* Recommended: SDXL Scribble for best sketch fidelity
	*/
	async refineSketch(request: SketchRefinementRequest): Promise<{
	imageUrl: string;
	seed: number;
	processingTimeMs: number;
	}> {
	const startTime = Date.now();
	try {
	// Endpoint: SDXL Scribble ControlNet
	const response = await axios.post(
	`${this.baseUrl}/sd-controlnet-scribble-sdxl`,
	{
	sketch_image: request.sketchImage,
	prompt: request.prompt,
	negative_prompt: 'blurry, low quality, distorted, watermark',
	guidance_scale: request.guidanceScale ?? 7.5,
	control_strength: request.controlStrength ?? 0.9,
	num_outputs: request.numOutputs ?? 1,
	model: 'sdxl', // SDXL for best quality
	num_inference_steps: 30,
	seed: Math.floor(Math.random() * 1_000_000),
	},
	{
	headers: {
	'x-api-key': this.apiKey,
	'Content-Type': 'application/json',
	},
	},
	);
	if (!response.data?.images?.[0]) {
	throw new Error('No image returned from Segmind');
	}
	const imageBas64 = response.data.images[0];
	const imageBuffer = Buffer.from(imageBas64, 'base64');
	const uploadUrl = await this.storageService.uploadImage(
	imageBuffer,
	`refinement/${Date.now()}.png`,
	);
	return {
	imageUrl: uploadUrl,
	seed: response.data.seed,
	processingTimeMs: Date.now() - startTime,
	};
	} catch (error) {
	this.logger.error('Segmind refinement failed:', error);
	throw error;
	}
	}
	/**
	* Refine specific areas using ControlNet Inpainting
	*/
	async refineInpaintRegion(request: {
	originalImage: string; // Base64 PNG
	maskImage: string; // White area = inpaint, black = preserve
	prompt: string;
	inpaintStrength?: number; // 0-1, default 0.8
	}): Promise<{ imageUrl: string }> {
	const response = await axios.post(
	`${this.baseUrl}/sd-controlnet-inpaint-sdxl`,
	{
	image: request.originalImage,
	mask: request.maskImage,
	prompt: request.prompt,
	inpaint_strength: request.inpaintStrength ?? 0.8,
	guidance_scale: 7.5,
	num_outputs: 1,
	},
	{
	headers: {
	'x-api-key': this.apiKey,
	},
	},
	);
	const imageBuffer = Buffer.from(response.data.images[0], 'base64');
	const uploadUrl = await this.storageService.uploadImage(imageBuffer, '...');
	return { imageUrl: uploadUrl };
	}
	/**
	* Canny edge detection variant
	* Better for preserving precise structure
	*/
	async refineWithCannyEdges(request: {
	sketchImage: string;
	prompt: string;
	cannyThresholdLow?: number; // Default 100
	cannyThresholdHigh?: number; // Default 200
	}): Promise<{ imageUrl: string; seed: number }> {
	// Segmind automatically applies Canny preprocessing
	const response = await axios.post(
	`${this.baseUrl}/sd-controlnet-canny-sdxl`,
	{
	sketch_image: request.sketchImage,
	prompt: request.prompt,
	guidance_scale: 8.0, // Canny usually needs higher guidance
	control_strength: 0.95,
	num_outputs: 1,
	},
	{
	headers: {
	'x-api-key': this.apiKey,
	},
	},
	);
	const imageBuffer = Buffer.from(response.data.images[0], 'base64');
	const uploadUrl = await this.storageService.uploadImage(imageBuffer, '...');
	return { imageUrl: uploadUrl, seed: response.data.seed };
	}
	}
	```

🤖 Prompt for AI Agents

In AI_SKETCH_REFINEMENT_WORKFLOWS.md around lines 338 to 475, there's a typo on
line 394 where imageBas64 should be imageBase64; rename the variable and all its
uses to imageBase64, and use Buffer.from(imageBase64, 'base64') accordingly.
Also ensure the class has the storageService dependency injected (e.g., add a
constructor param like private readonly storageService: YourStorageServiceType)
and that logger (this.logger) and any other services used are declared and
injected so uploadImage and logging calls compile.

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

Improve type safety in Fabric.js integration.

Line 496 initializes sketchCanvas: null but the type annotation declares Canvas (non-nullable). Update the type to Canvas | null, or ensure initialization is proper. Additionally, the error case on line 543 silently swallows the error—consider logging or notifying the user of refinement failures.

-interface RefinementState {
-  sketchCanvas: Canvas;
+interface RefinementState {
+  sketchCanvas: Canvas | null;

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	// pages/studio/refinement-panel.tsx
	import React, { useState } from 'react';
	import { Canvas } from 'fabric';
	interface RefinementState {
	sketchCanvas: Canvas;
	refinedImageUrl: string | null;
	prompt: string;
	guidanceScale: number;
	isProcessing: boolean;
	processingTime: number;
	}
	export function SketchRefinementPanel() {
	const [state, setState] = useState<RefinementState>({
	sketchCanvas: null,
	refinedImageUrl: null,
	prompt: 'manga illustration, clean linework, detailed, professional',
	guidanceScale: 7.5,
	isProcessing: false,
	processingTime: 0,
	});
	const handleRefineSketch = async () => {
	if (!state.sketchCanvas) return;
	setState(prev => ({ ...prev, isProcessing: true }));
	const startTime = Date.now();
	try {
	// Export sketch as PNG
	const sketchBlob = await new Promise<Blob>(resolve =>
	state.sketchCanvas.toBlob(resolve, 'image/png'),
	);
	const sketchBase64 = await blobToBase64(sketchBlob);
	// Call backend API
	const response = await fetch('/api/refine/sketch', {
	method: 'POST',
	headers: { 'Content-Type': 'application/json' },
	body: JSON.stringify({
	sketch: sketchBase64,
	prompt: state.prompt,
	guidanceScale: state.guidanceScale,
	strength: 0.9,
	}),
	});
	if (!response.ok) {
	throw new Error(`API error: ${response.statusText}`);
	}
	const result = await response.json();
	setState(prev => ({
	...prev,
	refinedImageUrl: result.imageUrl,
	processingTime: Date.now() - startTime,
	isProcessing: false,
	}));
	} catch (error) {
	console.error('Refinement failed:', error);
	setState(prev => ({ ...prev, isProcessing: false }));
	}
	};
	return (
	<div className="refinement-panel">
	{/* Sketch Canvas */}
	<div className="sketch-section">
	<h3>Sketch Input</h3>
	<SketchCanvas
	onChange={(canvas) => setState(prev => ({ ...prev, sketchCanvas: canvas }))}
	/>
	</div>
	{/* Controls */}
	<div className="controls-section">
	<div className="control-group">
	<label>Prompt</label>
	<textarea
	value={state.prompt}
	onChange={(e) => setState(prev => ({ ...prev, prompt: e.target.value }))}
	placeholder="Describe desired style and details"
	rows={4}
	/>
	</div>
	<div className="control-group">
	<label>Guidance Scale: {state.guidanceScale.toFixed(1)}</label>
	<input
	type="range"
	min="0.5"
	max="15"
	step="0.5"
	value={state.guidanceScale}
	onChange={(e) =>
	setState(prev => ({ ...prev, guidanceScale: parseFloat(e.target.value) }))
	}
	/>
	<small>Higher = stricter adherence to sketch structure</small>
	</div>
	<button
	onClick={handleRefineSketch}
	disabled={state.isProcessing}
	className="btn btn-primary"
	>
	{state.isProcessing ? 'Refining...' : 'Refine Sketch'}
	</button>
	{state.processingTime > 0 && (
	<p className="processing-info">
	Processed in {state.processingTime}ms
	</p>
	)}
	</div>
	{/* Comparison Viewer */}
	{state.refinedImageUrl && (
	<ComparisonViewer
	originalImage={state.sketchCanvas.toDataURL('image/png')}
	refinedImage={state.refinedImageUrl}
	mode="split" // or "slider", "fade", "overlay"
	/>
	)}
	</div>
	);
	}
	async function blobToBase64(blob: Blob): Promise<string> {
	return new Promise((resolve, reject) => {
	const reader = new FileReader();
	reader.onloadend = () => resolve(reader.result as string);
	reader.onerror = reject;
	reader.readAsDataURL(blob);
	});
	}
	```
	// pages/studio/refinement-panel.tsx
	import React, { useState } from 'react';
	import { Canvas } from 'fabric';
	interface RefinementState {
	sketchCanvas: Canvas | null;
	refinedImageUrl: string | null;
	prompt: string;
	guidanceScale: number;
	isProcessing: boolean;
	processingTime: number;
	}
	export function SketchRefinementPanel() {
	const [state, setState] = useState<RefinementState>({
	sketchCanvas: null,
	refinedImageUrl: null,
	prompt: 'manga illustration, clean linework, detailed, professional',
	guidanceScale: 7.5,
	isProcessing: false,
	processingTime: 0,
	});
	const handleRefineSketch = async () => {
	if (!state.sketchCanvas) return;
	setState(prev => ({ ...prev, isProcessing: true }));
	const startTime = Date.now();
	try {
	// Export sketch as PNG
	const sketchBlob = await new Promise<Blob>(resolve =>
	state.sketchCanvas.toBlob(resolve, 'image/png'),
	);
	const sketchBase64 = await blobToBase64(sketchBlob);
	// Call backend API
	const response = await fetch('/api/refine/sketch', {
	method: 'POST',
	headers: { 'Content-Type': 'application/json' },
	body: JSON.stringify({
	sketch: sketchBase64,
	prompt: state.prompt,
	guidanceScale: state.guidanceScale,
	strength: 0.9,
	}),
	});
	if (!response.ok) {
	throw new Error(`API error: ${response.statusText}`);
	}
	const result = await response.json();
	setState(prev => ({
	...prev,
	refinedImageUrl: result.imageUrl,
	processingTime: Date.now() - startTime,
	isProcessing: false,
	}));
	} catch (error) {
	console.error('Refinement failed:', error);
	setState(prev => ({ ...prev, isProcessing: false }));
	}
	};
	return (
	<div className="refinement-panel">
	{/* Sketch Canvas */}
	<div className="sketch-section">
	<h3>Sketch Input</h3>
	<SketchCanvas
	onChange={(canvas) => setState(prev => ({ ...prev, sketchCanvas: canvas }))}
	/>
	</div>
	{/* Controls */}
	<div className="controls-section">
	<div className="control-group">
	<label>Prompt</label>
	<textarea
	value={state.prompt}
	onChange={(e) => setState(prev => ({ ...prev, prompt: e.target.value }))}
	placeholder="Describe desired style and details"
	rows={4}
	/>
	</div>
	<div className="control-group">
	<label>Guidance Scale: {state.guidanceScale.toFixed(1)}</label>
	<input
	type="range"
	min="0.5"
	max="15"
	step="0.5"
	value={state.guidanceScale}
	onChange={(e) =>
	setState(prev => ({ ...prev, guidanceScale: parseFloat(e.target.value) }))
	}
	/>
	<small>Higher = stricter adherence to sketch structure</small>
	</div>
	<button
	onClick={handleRefineSketch}
	disabled={state.isProcessing}
	className="btn btn-primary"
	>
	{state.isProcessing ? 'Refining...' : 'Refine Sketch'}
	</button>
	{state.processingTime > 0 && (
	<p className="processing-info">
	Processed in {state.processingTime}ms
	</p>
	)}
	</div>
	{/* Comparison Viewer */}
	{state.refinedImageUrl && (
	<ComparisonViewer
	originalImage={state.sketchCanvas.toDataURL('image/png')}
	refinedImage={state.refinedImageUrl}
	mode="split" // or "slider", "fade", "overlay"
	/>
	)}
	</div>
	);
	}
	async function blobToBase64(blob: Blob): Promise<string> {
	return new Promise((resolve, reject) => {
	const reader = new FileReader();
	reader.onloadend = () => resolve(reader.result as string);
	reader.onerror = reject;
	reader.readAsDataURL(blob);
	});
	}

🤖 Prompt for AI Agents

In AI_SKETCH_REFINEMENT_WORKFLOWS.md around lines 480–620 (notably lines ~496
and ~543), the RefinementState declares sketchCanvas as Canvas but initializes
it to null and the catch block only console.errors without surfacing the
failure; change the type to Canvas | null (or otherwise ensure non-null
initialization) so state typing matches initialization and update the catch
handler to log the error and set a user-visible error flag/message in state
(e.g., set an error string or toast trigger) so failures are not silently
swallowed and the UI can reflect the failure.

[coderabbitai]

🛠️ Refactor suggestion | 🟠 Major

Consistently specify language identifiers in all fenced code blocks.

Code blocks throughout this file lack language identifiers, affecting syntax highlighting and accessibility. Examples: bash (lines 29-32, 36-47, 142-156, 206-216, 325-328), typescript (lines 68-80, 104-138), and others.

Also applies to: 68-80, 104-138, 142-156, 206-216, 253-294, 298-313, 325-328, 334-339, 472-480

🤖 Prompt for AI Agents

In CANVAS_STORAGE_QUICK_START.md around lines 28-47, 68-80, 104-138, 142-156,
206-216, 253-294, 298-313, 325-328, 334-339 and 472-480: update every fenced
code block to include the correct language identifier (e.g., ```bash for shell
snippets, ```typescript or ```ts for TS snippets, etc.), ensuring each block
uses the appropriate language tag and all code fences are consistent across the
file for proper syntax highlighting and accessibility.

[coderabbitai]

🛠️ Refactor suggestion | 🟠 Major

Wrap bare URLs in link markup for proper documentation rendering.

Lines 730-734 contain bare URLs that should be wrapped in Markdown link syntax. This improves both visual clarity and accessibility.

Example fix:

-- **Prisma Docs:** https://www.prisma.io/docs/
+- **Prisma Docs:** [https://www.prisma.io/docs/](https://www.prisma.io/docs/)

Apply similar formatting to all 5 URLs in the Support & Resources section.

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	- **Prisma Docs:** https://www.prisma.io/docs/
	- **Supabase Docs:** https://supabase.com/docs/
	- **NestJS Docs:** https://docs.nestjs.com/
	- **Socket.io Docs:** https://socket.io/docs/
	- **Compression:** https://github.com/nodeca/pako
	- **Prisma Docs:** [https://www.prisma.io/docs/](https://www.prisma.io/docs/)
	- **Supabase Docs:** [https://supabase.com/docs/](https://supabase.com/docs/)
	- **NestJS Docs:** [https://docs.nestjs.com/](https://docs.nestjs.com/)
	- **Socket.io Docs:** [https://socket.io/docs/](https://socket.io/docs/)
	- **Compression:** [https://github.com/nodeca/pako](https://github.com/nodeca/pako)

🧰 Tools

🪛 markdownlint-cli2 (0.18.1)

730-730: Bare URL used

(MD034, no-bare-urls)

---

731-731: Bare URL used

(MD034, no-bare-urls)

---

732-732: Bare URL used

(MD034, no-bare-urls)

---

733-733: Bare URL used

(MD034, no-bare-urls)

---

734-734: Bare URL used

(MD034, no-bare-urls)

🤖 Prompt for AI Agents

In CANVAS_STORAGE_QUICK_START.md around lines 730 to 735 the Support & Resources
list contains bare URLs; convert each into Markdown link syntax by replacing
each plain URL with [label](url) form (e.g., use descriptive labels like "Prisma
Docs", "Supabase Docs", "NestJS Docs", "Socket.io Docs", "Compression (pako)"
and link them to their respective URLs) so the links render properly and improve
accessibility.

[coderabbitai]

⚠️ Potential issue | 🟠 Major

Document scope and priority mismatch.

The document is marked as "Research Documentation (Lower Priority - Future Implementation)" yet spans 1,262 lines with extensive tool analysis, implementation patterns, and architectural blueprints. This thoroughness is commendable for future reference, but the depth may not be proportional to current PR priorities (which focus on queues, observability, export, and persistence infrastructure).

Recommendation: Consider whether this research documentation should be condensed into a concise decision summary (200–300 lines) referencing external resources, or deferred to a dedicated research/design doc repo. The current PR adds foundational infrastructure (queues, observability, Prisma) that enables future collaboration features; detailed collaboration patterns could follow once those layers stabilize.

Would you like me to suggest a condensed version focusing on the top 3–5 key decisions and deferring detailed tool analysis?

🤖 Prompt for AI Agents

In COLLABORATION_ARCHITECTURE.md around lines 1 to 6, the document's status
label ("Research Documentation (Lower Priority - Future Implementation)")
conflicts with its very large, detailed contents; condense or relocate it:
create a short 200–300 line decision summary in this repo that captures the top
3–5 architectural decisions, rationale, and next steps, add links to external
references and tooling analysis hosted in a new dedicated research/design-docs
repo (or a docs/research directory) for deep dives, update the header/status to
clearly indicate where the detailed material now lives and mark the remaining
details as deferred until core infra (queues, observability, persistence)
stabilizes, and leave a brief TOC/README in this file pointing to the full
research doc location.

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

🧩 Analysis chain

Verify external reference links are current and accessible.

The "References and Resources" section cites academic papers, tools (Yjs, Automerge, Socket.IO, Figma), and blogs. To ensure long-term utility of this documentation:

1. Verify the Figma, tldraw, and Excalidraw blog links (lines 1250–1252) are still active.
2. Add version pinning for library recommendations (e.g., "Yjs v13.x+") to avoid stale guidance.
3. Consider adding a "Last Reviewed" date for each external reference.

Run the following quick check on reference URLs:

---

🏁 Script executed:

#!/bin/bash
# Verify external documentation links
curl -s -o /dev/null -w "%{http_code}" "https://www.figma.com/blog/how-figmas-multiplayer-technology-works/"
curl -s -o /dev/null -w "%{http_code}" "https://tldraw.dev/docs/collaboration"
curl -s -o /dev/null -w "%{http_code}" "https://blog.excalidraw.com/building-excalidraw-p2p-collaboration-feature/"
curl -s -o /dev/null -w "%{http_code}" "https://crdt.tech/"

Length of output: 12

---

Update reference links and add version guidance for long-term accuracy.

Link verification found 3 of 4 references are directly accessible (200), but the Excalidraw blog link returns HTTP 308 (permanent redirect)—manually verify it resolves to the intended article before or after merge. Additionally:

• Add version guidance for library recommendations (e.g., "Yjs v13.x+", "Automerge v2.x+") to prevent outdated advice.
• Optionally include a "Last Reviewed" date in the References section to signal documentation freshness.

🤖 Prompt for AI Agents

In COLLABORATION_ARCHITECTURE.md around lines 1236 to 1253, the References
section contains a link that redirects (Excalidraw blog returns HTTP 308) and
lacks version guidance and a revision date; verify and replace the Excalidraw
URL with the final resolved URL (follow the redirect to ensure it points to the
intended article), add explicit recommended version ranges for libraries (e.g.,
"Yjs v13.x+", "Automerge v2.x+") next to the Tools & Libraries entries, and add
a "Last Reviewed: YYYY-MM-DD" line to the References header to indicate when the
links and versions were validated.

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

Missing language identifier for fenced code block (MD040).

The code block starting at line 37 should specify a language for proper syntax highlighting. Change the opening delimiter from ``` to ```bash or ```text.

-```
+```bash
 Backend:
 ├── Node.js + Express

🧰 Tools

🪛 markdownlint-cli2 (0.18.1)

37-37: Fenced code blocks should have a language specified

(MD040, fenced-code-language)

🤖 Prompt for AI Agents

In COLLABORATION_QUICK_REFERENCE.md around lines 37 to 57, the fenced code block
lacks a language identifier causing MD040; update the opening fence from ``` to
a language-labeled fence such as ```bash or ```text (choose whichever best fits)
so the block becomes ```bash (or ```text) and keep the rest of the block
unchanged to enable proper syntax highlighting.