Fix API request errors with MCP functions incompatible with OpenAI strict mode

[kevinvandijk]

Some MCP servers, like the Github one have tools that are not defining the additionalProperties param. This is required with native tools in strict mode. This PR adds the param when it's missing.

[changeset-bot]

🦋 Changeset detected

Latest commit: fdc0c0a

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
kilo-code	Patch

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[kiloconnect]

✅ No Issues Found

5 files reviewed | Confidence: 92% | Recommendation: Merge

Review Details

Files:

• .changeset/stale-lines-care.md - Changeset file (trivial)
• src/api/providers/kilocode/openai-strict-schema.ts - New utility function
• src/api/providers/base-provider.ts - Integration of normalization
• src/api/providers/openai-native.ts - Integration of normalization
• src/api/providers/__tests__/openai-strict-schema.spec.ts - Test coverage

Analysis:

The PR correctly addresses the issue where MCP servers (like GitHub) define tool schemas without the additionalProperties field, which is required by OpenAI's strict mode. The solution:

1. New utility function normalizeObjectAdditionalPropertiesFalse() recursively traverses JSON schemas and adds additionalProperties: false to any object schema with properties that doesn't already have it defined.

2. Comprehensive recursion - The function handles:

   • Nested properties
   • Schema composition keywords (anyOf, oneOf, allOf)
   • Array items
   • $defs and definitions containers
   • additionalProperties when it's a schema object itself

3. Safe behavior - Only adds the property when undefined, preserving intentional dictionary semantics when additionalProperties is explicitly set.

4. Applied in two locations:

   • base-provider.ts:91 - For providers using convertToolSchemaForOpenAI()
   • openai-native.ts:296-298 - For the native OpenAI handler's Responses API

5. Test coverage - Tests verify both the standalone function and the integration through BaseProvider.

Minor note: There's a typo in a comment at line 300 (kilocode_chang end instead of kilocode_change end), but this is cosmetic and doesn't affect functionality.

Checked: Security, bugs, edge cases, error handling, type safety