Greptile Summary

This PR fixes a Google Generative AI API conflict where systemInstruction, tools, and toolConfig were being sent alongside cachedContent, which the API rejects because the cached context already contains those fields. The fix is applied at two layers: a guard in buildGoogleGenerativeAiParams (for the direct options.cachedContent path) and a payload-patch deletion in google-prompt-cache.ts (for the managed-cache path where cachedContent is injected after the params are built).

Confidence Score: 5/5

Safe to merge — targeted fix with good test coverage across both code paths.

The change is minimal and correctly handles both the direct-options path (guard in buildGoogleGenerativeAiParams) and the managed-cache path (payload-patch deletions in google-prompt-cache.ts). Tests cover the new behavior and verify the deletions explicitly.

No files require special attention.

_{Reviews (1): Last reviewed commit: "fix(google): omit cached content request..." | Re-trigger Greptile}

Good catch. Worth flagging the security implication beyond the API compliance fix: if systemInstruction is where a developer has placed access controls, content filters, or behavioral guardrails, silently omitting it when cachedContent is active means those guardrails don't fire for cached responses. A developer who assumes their system instruction applies universally would have no signal that cached sessions are running without it.The fix is correct — omitting incompatible fields rather than letting the API reject them. But the behavioral change deserves explicit documentation: cachedContent sessions run without systemInstruction, tools, and toolConfig. If any of those carry security-relevant logic, developers need to know that cached responses operate in a different trust context than non-cached ones.