feat: add CoStrict AI assistant support

[mini2s]

Add support for Costrict AI tool with slash commands and configuration template. Includes configurator, registry entries, templates, and comprehensive test coverage.

Openspec and CoStrict work together like magic. 👍👍👍 @TabishB

Summary by CodeRabbit

• New Features
  • Added Costrict as an available AI tool with OpenSpec slash command support, project configuration scaffolding, and README entry linking to its docs.
• Tests
  • Added comprehensive tests covering Costrict creation and update of slash command templates and config file, marker-preserving updates, error handling, and extend-mode behavior.

[coderabbitai]

Walkthrough

Adds first-class support for the CoStrict AI tool: README entry, AI_TOOLS config entry, CoStrictConfigurator, CoStrict slash-command configurator, template export and TemplateManager accessor, registry registrations, and comprehensive init/update tests exercising marker-bounded file updates and error cases.

Changes

Cohort / File(s)	Summary
Docs README.md	Adds CoStrict to the Supported Native Slash Commands table with OpenSpec slash commands and docs link.
Core config src/core/config.ts	Inserts { name: 'CoStrict', value: 'costrict', available: true, successLabel: 'CoStrict' } into exported AI_TOOLS.
Tool configurator src/core/configurators/costrict.ts, src/core/configurators/registry.ts	Adds CoStrictConfigurator (implements ToolConfigurator) that writes/updates COSTRICT.md using TemplateManager.getCostrictTemplate() and FileSystemUtils.updateFileWithMarkers; registers instance under key 'costrict'.
Slash command configurator src/core/configurators/slash/costrict.ts, src/core/configurators/slash/registry.ts	Adds CostrictSlashCommandConfigurator (extends SlashCommandConfigurator) with toolId = 'costrict', availability flag, per-command FILE_PATHS and FRONTMATTER mappings; registers it in slash configurator registry.
Templates src/core/templates/costrict-template.ts, src/core/templates/index.ts	Re-exports agentsRootStubTemplate as costrictTemplate, and adds TemplateManager.getCostrictTemplate() returning that template.
Tests test/core/init.test.ts, test/core/update.test.ts	Adds init and update tests for CoStrict/Costrict: creation and update of slash command files under .cospec/openspec/commands, creation/update/preservation of COSTRICT.md, marker-bounded updates, error/permission and update-edge-case scenarios.

Sequence Diagram(s)

sequenceDiagram
  participant CLI as CLI (init/update)
  participant Registry as Configurators Registry
  participant Template as TemplateManager
  participant FS as FileSystemUtils
  Note right of CLI: Init/Update invoked with CoStrict selected
  CLI->>Registry: lookup configurator 'costrict'
  Registry->>CLI: return CoStrictConfigurator / CostrictSlashConfigurator
  CLI->>Template: getCostrictTemplate()
  Template-->>CLI: costrictTemplate
  CLI->>FS: updateFileWithMarkers(path: COSTRICT.md, markers, template)
  alt file writable
    FS-->>CLI: write success
    CLI->>CLI: mark tool configured
  else write/read error
    FS-->>CLI: error logged (no throw)
  end

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Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~30 minutes

• Pay extra attention to:
  • test/core/update.test.ts — many edge cases and assertions.
  • src/core/configurators/slash/costrict.ts — ensure FILE_PATHS/FRONTMATTER align with other tools.
  • Registry entries consistency across src/core/config.ts, configurators/registry.ts, and slash/registry.ts.

Possibly related PRs

• feat: add CodeBuddy Code support to configuration and documentation #217 — Adds support for a new native slash-command tool with config and configurator registration (similar pattern).

Suggested reviewers

• TabishB

Poem

🐰 I hopped a trail of markers bright,

CoStrict templates stitched just right,
Registries hum and tests applaud,
Files updated—no rabbit fraud,
Tiny hop, big launch tonight! 🥕

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title Check	✅ Passed	The PR title "feat: add CoStrict AI assistant support" accurately and specifically summarizes the primary objective of the changeset. The entire PR is focused on introducing CoStrict as a new AI tool throughout the codebase, including configurators, slash commands, templates, registry entries, and comprehensive test coverage. The title is concise, clear, and directly reflects the main change without vague language or unnecessary noise, making it easy for teammates to understand the core purpose of this PR.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[coderabbitai]

Actionable comments posted: 0

🧹 Nitpick comments (4)

src/core/configurators/slash/costrict.ts (2)

4-8: Lock in key coverage with satisfies/as const

Use TS satisfies + as const to guarantee compile-time exhaustiveness and avoid accidental mutation.

Apply:

-const FILE_PATHS: Record<SlashCommandId, string> = {
-  proposal: '.cospec/openspec/commands/openspec-proposal.md',
-  apply: '.cospec/openspec/commands/openspec-apply.md',
-  archive: '.cospec/openspec/commands/openspec-archive.md'
-};
+const FILE_PATHS = {
+  proposal: '.cospec/openspec/commands/openspec-proposal.md',
+  apply: '.cospec/openspec/commands/openspec-apply.md',
+  archive: '.cospec/openspec/commands/openspec-archive.md',
+} as const satisfies Record<SlashCommandId, string>;

If your TS version < 4.9, drop satisfies and keep as const, or keep the original typing.

---

10-23: Same for FRONTMATTER map

Harden typing/immutability for the frontmatter map.

-const FRONTMATTER: Record<SlashCommandId, string> = {
+const FRONTMATTER = {
   proposal: `---
 description: "Scaffold a new OpenSpec change and validate strictly."
 argument-hint: feature description or request
 ---`,
   apply: `---
 description: "Implement an approved OpenSpec change and keep tasks in sync."
 argument-hint: change-id
 ---`,
   archive: `---
 description: "Archive a deployed OpenSpec change and update specs."
 argument-hint: change-id
 ---`
-};
+} as const satisfies Record<SlashCommandId, string>;

test/core/update.test.ts (2)

822-861: Good parity test for Costrict slash refresh

Covers marker-only updates and expected log lines. Matches path and guardrail content.

Consider extracting a shared helper (e.g., assertSlashUpdateBetweenMarkers(tool, file)) to reduce duplication across tools.

---

966-1005: Make error-path test OS-agnostic

chmod(0o444) can be flaky on Windows. Rely on the writeFile mock alone to simulate EACCES and keep the test portable.

-    await fs.chmod(costrictPath, 0o444); // Read-only
@@
-    // Restore permissions for cleanup
-    await fs.chmod(costrictPath, 0o644);

The mock already throws for COSTRICT.md, so behavior is preserved without filesystem permission fiddling.

If you want to keep chmod, guard it:

if (os.platform() !== 'win32') { await fs.chmod(costrictPath, 0o444); }

📜 Review details

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between fb1d37e and 4020ce1.

📒 Files selected for processing (10)

• README.md (1 hunks)
• src/core/config.ts (1 hunks)
• src/core/configurators/costrict.ts (1 hunks)
• src/core/configurators/registry.ts (2 hunks)
• src/core/configurators/slash/costrict.ts (1 hunks)
• src/core/configurators/slash/registry.ts (3 hunks)
• src/core/templates/costrict-template.ts (1 hunks)
• src/core/templates/index.ts (2 hunks)
• test/core/init.test.ts (1 hunks)
• test/core/update.test.ts (1 hunks)

🧰 Additional context used

🧬 Code graph analysis (8)

src/core/configurators/slash/registry.ts (1)

src/core/configurators/slash/costrict.ts (1)

• CostrictSlashCommandConfigurator (25-36)

src/core/templates/costrict-template.ts (2)

src/core/init.ts (1)

• configureRootAgentsStub (788-803)

src/core/configurators/agents.ts (1)

• AgentsStandardConfigurator (7-23)

src/core/config.ts (1)

src/core/init.ts (3)

• formatToolNames (919-934)
• promptForAITools (559-630)
• displaySuccessMessage (805-917)

src/core/configurators/costrict.ts (4)

src/core/configurators/base.ts (1)

• ToolConfigurator (1-6)

src/core/templates/index.ts (1)

• TemplateManager (14-47)

src/utils/file-system.ts (1)

• FileSystemUtils (44-187)

src/core/config.ts (1)

• OPENSPEC_MARKERS (3-6)

test/core/init.test.ts (1)

src/utils/file-system.ts (1)

• fileExists (76-86)

src/core/configurators/registry.ts (2)

src/core/configurators/costrict.ts (1)

• CostrictConfigurator (7-23)

src/core/configurators/agents.ts (1)

• AgentsStandardConfigurator (7-23)

test/core/update.test.ts (1)

src/utils/file-system.ts (2)

• FileSystemUtils (44-187)
• fileExists (76-86)

src/core/configurators/slash/costrict.ts (1)

src/core/templates/index.ts (1)

• SlashCommandId (50-50)

🔇 Additional comments (15)

src/core/configurators/slash/registry.ts (1)

15-15: LGTM! Clean integration following established patterns.

The Costrict slash command configurator is properly imported, instantiated, and registered following the same pattern as existing tools.

Also applies to: 34-34, 49-49

src/core/config.ts (1)

24-24: LGTM! Proper tool configuration.

The Costrict entry is correctly positioned alphabetically and includes all required fields with consistent naming conventions.

README.md (1)

95-95: LGTM! Clear and consistent documentation.

The Costrict entry follows the established documentation pattern with correct command names, directory path, and reference link.

src/core/configurators/registry.ts (1)

5-5: LGTM! Proper registry integration.

The CostrictConfigurator is correctly imported, instantiated, and registered with the appropriate key that matches the tool identifier in the configuration.

Also applies to: 15-15, 21-21

src/core/templates/index.ts (1)

5-5: LGTM! Consistent template management.

The Costrict template is properly imported and exposed through a static method following the established pattern for other tool templates.

Also applies to: 36-38

src/core/templates/costrict-template.ts (1)

1-1: LGTM! Appropriate template reuse.

The re-export creates a named alias for the agents root stub template, which is an efficient approach when tools share the same template content.

test/core/init.test.ts (3)

999-1039: LGTM! Comprehensive slash command file tests.

The test thoroughly validates the creation of Costrict slash command files with proper paths (.cospec/openspec/commands/), frontmatter, markers, and content. Follows established testing patterns for other tools.

---

1041-1051: LGTM! Proper extend mode testing.

The test correctly verifies that Costrict is marked as already configured during extend mode, following the same pattern as other tools.

---

1053-1084: LGTM! Complete COSTRICT.md file handling tests.

Both tests properly verify COSTRICT.md creation with markers and updating existing files while preserving custom content. Follows established patterns for tool-specific configuration files.

src/core/configurators/costrict.ts (1)

1-23: LGTM! Well-structured configurator implementation.

The CostrictConfigurator properly implements the ToolConfigurator interface and follows the exact pattern established by other tool configurators. The implementation correctly:

• Uses marker-based file updates to preserve custom content
• Places COSTRICT.md in the project root
• Retrieves the appropriate template via TemplateManager

test/core/update.test.ts (4)

863-896: Skip-create behavior validated

Ensures proposal/archive aren’t created when only apply exists. Solid.

---

898-934: COSTRICT.md update behavior validated

Asserts managed block update and logging. Looks correct.

---

936-946: No creation on absence

Confirms COSTRICT.md isn’t created on update. Good negative coverage.

---

948-964: Preserves content outside markers

Verifies only managed region changes; mirrors Windsurf test. Good.

src/core/configurators/slash/costrict.ts (1)

25-36: Registry wiring verified and correct

CostrictSlashCommandConfigurator is properly imported, instantiated, and registered in src/core/configurators/slash/registry.ts (lines 15, 34, 49). Top-level registry also correctly wires CostrictConfigurator. No issues found.

[TabishB]

Thanks for this @mini2s Good to merge 🚀

[mini2s]

Thanks for this @mini2s Good to merge 🚀

Looking forward to the new version of Openspec adding CoStrict support 🤝