Greptile Summary

This PR adds a sanitizeRequiredFields() helper in the Gemini schema-cleaning path that filters required array entries to only those with a declared own property in properties, dropping the array entirely when no valid entries remain. It is applied at every exit point of cleanSchemaForGeminiWithDefs (post-union-flattening and the plain-object path), and is gated exclusively to the Gemini provider via the existing cleanSchemaForGemini call-chain, so non-Gemini schemas are unaffected. The new tests cover the key cases well: phantom keys, all-valid keys, all-phantom keys, inherited prototype keys, nested objects, and the non-Gemini passthrough.

Confidence Score: 5/5

Safe to merge — fix is scoped, well-tested, and doesn't affect non-Gemini providers.

No P0 or P1 issues found. The sanitizeRequiredFields helper is logically correct, uses Object.hasOwn to avoid prototype-key false positives, and mutates only freshly-created objects so callers are never surprised. Non-Gemini behavior is explicitly preserved and tested.

No files require special attention.

_{Reviews (1): Last reviewed commit: "fix: sanitize required fields in tool sc..." | Re-trigger Greptile}

Landed via rebase onto main.

• Gate: pnpm check; pnpm test src/agents/schema/clean-for-gemini.test.ts src/agents/pi-tools.schema.test.ts src/plugin-sdk/provider-tools.test.ts; pnpm build
• Full pnpm test was attempted locally and hit unrelated timeout/env-sensitive failures across non-touched shards under high parallelism.
• Land commit: 3d2cda5
• Merge commit: fe1fd05

Thanks @xxxxxmax!