refactor(core): centralize core tool definitions and support model-specific schemas

[aishaneeshah]

Summary

Centralizes core tool definitions and implements a robust, model-aware architecture for dynamic tool schemas and descriptions.

Details

1. Model-Aware Infrastructure

• Dynamic Overrides: Enhanced ToolDefinition to support an optional overrides callback, allowing declarations (descriptions, schemas) to vary based on the target model.
• Enhanced Resolver: Updated resolveToolDeclaration to apply model-specific overrides, ensuring the API always receives the most optimized tool definition for the resolved model.
• Unit Testing: Added comprehensive tests in resolver.test.ts to verify override logic (e.g., description updates, schema preservation).

2. Core Tool Consolidation

• Remaining Tools Integrated: Completed the refactor for glob, grep_search, list_directory, and write_file. These now pull descriptions and schemas from the centralized coreTools.ts.
• Standardized Late-Binding: Implemented getSchema(modelId) across all core tools, fully enabling the model-aware resolution pattern.
• Consistency Fixes: Standardized on parametersJsonSchema across all definitions and fixed property mismatches in read-file and run_shell_command.

3. Architectural Cleanup

• Name Centralization: Consolidated tool name constants into coreTools.ts, with tool-names.ts re-exporting them to prevent circular dependencies and maintain a single source of truth.
• Fidelity Guarantee: Verified that all refactored schemas exactly match the original hardcoded definitions on main.

Related Issues

Part of #17958

How to Validate

Run core package unit tests:

npm test -w @google/gemini-cli-core -- src/tools/write-file.test.ts src/tools/grep.test.ts src/tools/glob.test.ts src/tools/ls.test.ts src/tools/read-file.test.ts src/tools/shell.test.ts src/tools/definitions/resolver.test.ts

Run E2E validation:

npm run test:e2e

Pre-Merge Checklist

• Updated relevant documentation and README (if needed)
• Added/updated tests (if needed)
• Noted breaking changes (if any)
• Validated on required platforms/methods:
  • Linux
    • npm run

[gemini-code-assist]

Summary of Changes

Hello @aishaneeshah, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly refactors the core tool management system by centralizing tool definitions and introducing support for model-specific schema overrides. The changes aim to improve the flexibility and maintainability of tool declarations, allowing for dynamic adjustments based on the AI model in use. This architectural enhancement ensures that the system can adapt to different model capabilities and requirements more effectively, while also resolving existing circular dependencies for a cleaner codebase.

Highlights

• Centralized Tool Definitions: Core tool descriptions and JSON schemas for read_file, write_file, grep_search, glob, list_directory, and run_shell_command have been moved to a single, centralized location (packages/core/src/tools/definitions/coreTools.ts).
• Model-Specific Schema Overrides: A new mechanism has been introduced to allow tool schemas to be dynamically adjusted based on the modelId. Each tool now implements a getSchema(modelId) method, leveraging a resolveToolDeclaration helper to apply model-specific overrides, such as different match limits for grep_search.
• Dynamic Tool Updates in Chat: The GeminiClient and GeminiChat classes have been updated to support late-binding of tool schemas. Tools are now dynamically updated when the active model changes during a chat session, ensuring the correct model-specific tool definitions are always used.
• Architectural Improvements: Circular dependencies between tool implementations and tool name constants have been resolved by centralizing tool names alongside their definitions, leading to a cleaner and more maintainable architecture.

Changelog

• packages/core/src/core/client.test.ts
  • Updated mock GeminiChat instances to include a setTools method, reflecting changes in the GeminiChat interface.
• packages/core/src/core/client.ts
  • Modified the setTools method to accept an optional modelId and retrieve model-specific function declarations from the ToolRegistry.
  • Introduced lastUsedModelId to optimize tool updates, preventing redundant calls.
  • Implemented a callback in the GeminiChat constructor to dynamically update tools when the model changes.
  • Ensured tools are updated with the final modelToUse during a runTurn operation.
• packages/core/src/core/geminiChat.ts
  • Added an optional onModelChanged callback to its constructor, allowing external logic (like in GeminiClient) to react to model changes.
  • Integrated the onModelChanged callback within the runTurn method to update the chat's tools dynamically.
• packages/core/src/tools/snapshots/read-file.test.ts.snap
  • Added new snapshot tests for the ReadFileTool's getSchema method.
• packages/core/src/tools/snapshots/shell.test.ts.snap
  • Added new snapshot tests for the ShellTool's getSchema method.
• packages/core/src/tools/definitions/coreTools.ts
  • Introduced as a central repository for core tool definitions, including READ_FILE_DEFINITION, WRITE_FILE_DEFINITION, GREP_DEFINITION, GLOB_DEFINITION, LS_DEFINITION, and getShellDefinition.
  • Centralized tool name constants to prevent circular dependencies.
  • Includes model-specific overrides for tools like GREP_DEFINITION.
• packages/core/src/tools/definitions/resolver.test.ts
  • Added unit tests for the resolveToolDeclaration function, verifying its ability to apply model-specific overrides.
• packages/core/src/tools/definitions/resolver.ts
  • Implemented resolveToolDeclaration to process ToolDefinition objects and apply model-specific overrides to FunctionDeclarations.
• packages/core/src/tools/definitions/types.ts
  • Defined the ToolDefinition interface, which includes a base FunctionDeclaration and an optional overrides function for model-specific adjustments.
• packages/core/src/tools/glob.ts
  • Refactored to use GLOB_DEFINITION from coreTools.ts for its schema and description.
  • Implemented getSchema using resolveToolDeclaration to support model-specific schemas.
• packages/core/src/tools/grep.ts
  • Refactored to use GREP_DEFINITION from coreTools.ts for its schema and description.
  • Implemented getSchema using resolveToolDeclaration to support model-specific schemas.
• packages/core/src/tools/ls.ts
  • Refactored to use LS_DEFINITION from coreTools.ts for its schema and description.
  • Implemented getSchema using resolveToolDeclaration to support model-specific schemas.
• packages/core/src/tools/read-file.test.ts
  • Added tests for the new getSchema method of ReadFileTool.
• packages/core/src/tools/read-file.ts
  • Refactored to use READ_FILE_DEFINITION from coreTools.ts for its schema and description.
  • Implemented getSchema using resolveToolDeclaration to support model-specific schemas.
• packages/core/src/tools/shell.test.ts
  • Added tests for the new getSchema method of ShellTool.
• packages/core/src/tools/shell.ts
  • Removed platform-specific description generation functions, as these are now handled by getShellDefinition in coreTools.ts.
  • Refactored to use getShellDefinition from coreTools.ts for its schema and description.
  • Implemented getSchema using resolveToolDeclaration to support model-specific schemas.
• packages/core/src/tools/tool-names.ts
  • Updated to import and re-export tool name constants from coreTools.ts, resolving circular dependencies.
  • Added LS_TOOL_NAME_LEGACY for backward compatibility.
• packages/core/src/tools/tool-registry.test.ts
  • Added a test to ensure modelId is correctly passed to tool.getSchema() when retrieving function declarations.
• packages/core/src/tools/tool-registry.ts
  • Modified getFunctionDeclarations and getFunctionDeclarationsFiltered methods to accept an optional modelId parameter and pass it to the individual tool's getSchema method.
• packages/core/src/tools/tools.ts
  • Updated the Tool interface to include a getSchema(modelId?: string) method.
  • Introduced a deprecated readonly schema: FunctionDeclaration getter for backward compatibility.
  • The DeclarativeTool abstract class now implements both getSchema and the deprecated schema getter.
• packages/core/src/tools/write-file.ts
  • Refactored to use WRITE_FILE_DEFINITION from coreTools.ts for its schema and description.
  • Implemented getSchema using resolveToolDeclaration to support model-specific schemas.

Activity

• The author created the pull request with a detailed summary and explanation of the changes.
• The author has added and updated tests to cover the new functionality and refactored code.
• The author has validated the changes on Linux using npm run.

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[github-actions]

Size Change: -3.49 kB (-0.01%)

Total Size: 23.9 MB

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./bundle/gemini.js	23.9 MB	-3.49 kB (-0.01%)

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