prune unsupported properties from mcp schema for google

[j4ys0n]

No description provided.

[j4ys0n]

Automated review 🤖

Summary of Changes
Version bumped from 1.11.3 to 1.11.4. A new static ALLOWED_SCHEMA_KEYS set was introduced in GoogleMapper to whitelist supported JSON Schema properties for Google’s MCP tool parameter schemas. During schema normalization in mapToProviderParams, all keys not in this set are now stripped from tool parameter schemas, including unsupported fields like optional and examples. Unit test added to verify pruning behavior.

Key Changes & Positives

• Introduces explicit schema whitelisting via ALLOWED_SCHEMA_KEYS, improving robustness against unsupported schema extensions from upstream tools 🟢.
• Pruning logic applied consistently via Object.fromEntries(filter(...)), ensuring deterministic schema reduction in src/core/mapping/google.mapper.ts lines 286–288.
• New unit test confirms optional and examples are removed while required fields (type, description) remain in tests/unit/core/mapping/google.mapper.spec.ts lines 245–283.

Potential Issues & Recommendations

1. Issue / Risk: The nullable key is included in ALLOWED_SCHEMA_KEYS, but Google’s Function Calling API does not support nullable; this may cause runtime validation errors when generating tool calls.
   Impact: Tool registration could fail for schemas using nullable, especially if generated from OpenAPI specs or TypeScript union types.
   Recommendation: Remove nullable from ALLOWED_SCHEMA_KEYS and add handling for null types (e.g., convert to anyOf with null branch) or document limitation.
   Status: 🔴 Problem

2. Issue / Risk: propertyOrdering is included in ALLOWED_SCHEMA_KEYS, but Google’s Function Calling API does not recognize this field per public documentation.
   Impact: Pruned schema may still include unsupported metadata, risking silent ignored fields or future API rejections.
   Recommendation: Verify propertyOrdering support; if unsupported, remove from whitelist.
   Status: 🟡 Needs review

Language/Framework Checks

• TypeScript usage of Set for O(1) key lookup is appropriate and performant in google.mapper.ts lines 40–62.
• Schema pruning preserves valid Google-compatible keys (type, description, enum, etc.) while removing non-standard ones (optional, examples) as verified by test in google.mapper.spec.ts.

Security & Privacy
No security or privacy implications identified—schema pruning affects only metadata, not user data or credentials.

Build/CI & Ops
Version bump to 1.11.4 in package.json line 3 indicates a patch release; ensure changelog updated to reflect schema pruning behavior.

Tests
New test validates pruning of optional and examples keys, but no test covers edge cases like nested anyOf/oneOf with unsupported keys or nullable handling. Add tests for nested schema pruning and nullable behavior.

Approval Recommendation
Request changes

• Remove nullable and propertyOrdering from ALLOWED_SCHEMA_KEYS pending verification of Google API support.
• Add unit tests for nested schema pruning and nullable type handling.

[Copilot]

Pull request overview

This PR tightens Google tool/function parameter schema mapping by stripping schema keys that the Google GenAI FunctionDeclaration schema doesn’t support, preventing provider-side validation errors.

Changes:

• Add an allow-list based pruning step to GoogleMapper.cleanSchemaForGoogle() so only supported schema keywords are sent to Google.
• Add a unit test asserting that non-Google keys (e.g., optional, examples) are removed from tool parameter schemas.
• Bump package version 1.11.3 → 1.11.4.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
src/core/mapping/google.mapper.ts	Prunes cleaned JSON Schema objects down to Google-supported keys before building function declarations.
tests/unit/core/mapping/google.mapper.spec.ts	Adds coverage ensuring unsupported schema keys are stripped from tool parameter definitions.
package.json	Patch version bump for release.

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