fix(mcp): tolerate invalid output schema

[zerob13]

Summary

• Keep MCP tool discovery working when an optional output schema is malformed.
• Preserve strict input schema validation and warn when an invalid output schema is dropped.

Root cause

The built-in McDonald's MCP server returns an invalid output schema for mall-order-list at #/properties/data/items/properties/list/items/properties/type. The previous validation path rejected the entire tool list because of this optional field.

Validation

• pnpm exec vitest run --config vitest.config.ts test/main/mcp/schemaValidation.test.ts
• pnpm exec vitest run --config vitest.config.ts test/main/mcp/mcpClient.test.ts
• pnpm run typecheck:node
• pnpm run lint
• pnpm run i18n
• pnpm exec oxfmt --check src/main/mcp/schemaValidation.ts test/main/mcp/schemaValidation.test.ts

Summary by CodeRabbit

• Bug Fixes
  • Improved handling of invalid tool output schemas.
  • Tools with invalid schemas can now continue loading, with the problematic schema omitted and a warning recorded.

[coderabbitai]

Caution

Review failed

The pull request is closed.

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: 21a20265-37ce-47d3-97ba-902ac0b20e94

📥 Commits

Reviewing files that changed from the base of the PR and between 199e0c7 and 76211cd.

📒 Files selected for processing (1)

• src/main/mcp/schemaValidation.ts

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📝 Walkthrough

Walkthrough

validateAndCloneMcpTool now validates and clones optional outputSchema values. Invalid schemas trigger a warning and are omitted from the returned tool.

Changes

MCP output schema handling

Layer / File(s)	Summary
Output schema validation and assignment src/main/mcp/schemaValidation.ts	The validator clones valid outputSchema values. It logs a warning and omits invalid values. The returned tool uses the prevalidated schema.

Estimated code review effort: 2 (Simple) | ~10 minutes

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch codex/mcp-output-schema-compat

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[dosubot]

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