fix(google): bound tool schema expansion

[luvs01]

Summary

• Bound Google tool-schema traversal and recursive $ref expansion to 1,024 attempted schema nodes.
• Stop property, anyOf, and items traversal as soon as the budget is exhausted while retaining a valid, safely widened schema prefix.
• Track active references per expansion path and select only supported keys when merging $ref targets, avoiding repeated copies of unrelated annotations.
• Keep required names aligned with the properties that survive bounded sanitization.

The previous depth and dereference limits stopped simple recursion but did not bound acyclic branching definitions. A compact shared $defs graph could therefore expand into a large amount of local CPU and memory work before a Google-family request was serialized.

Verification

• bun test tests/google-tool-schema.test.ts — 24 passed
• bun test tests/google-wire-compiler.test.ts — 4 passed
• bun run typecheck
• bun run privacy:scan
• git diff --check
• Independent focused diff review — no remaining P0–P3 findings
• bun run test was attempted once. Unrelated Windows identity/catalog/history tests failed, then Bun 1.3.14 panicked after 1,242 seconds at 1.72 GB peak RSS; exact-head GitHub CI remains required.

Checklist

• Scope stays focused and avoids unrelated cleanup.
• Docs or release notes were updated when needed. No user-facing documentation change is needed for this internal bound.
• Security-sensitive changes were reviewed for secrets, auth, and unsafe defaults.

Review readiness checklist

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• All CI tests are green on my local testing.

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Summary by CodeRabbit

• Bug Fixes

  • Improved schema sanitization for recursive and deeply nested schemas.
  • Prevented runaway processing when schemas contain cycles, repeated references, or excessive properties.
  • Ensured invalid or incomplete required fields are safely filtered.
  • Added safe fallback behavior when schema size limits are exceeded.

• Tests

  • Expanded coverage for recursive references, shared definitions, wide schemas, arrays, and alternative schema branches.

[github-actions]

✅ Deterministic PR hygiene checks passed.

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📝 Walkthrough

Walkthrough

The Google tool-schema sanitizer now enforces a 1,024-node traversal budget, prevents recursive $ref expansion, filters unsupported reference fields, and keeps required entries aligned with retained properties. Tests cover bounded traversal and exhaustion behavior.

Changes

Google schema sanitization

Layer / File(s)	Summary
Bounded schema traversal src/adapters/google-tool-schema.ts:10-30, src/adapters/google-tool-schema.ts:58-67, src/adapters/google-tool-schema.ts:99-108, src/adapters/google-tool-schema.ts:141-151, src/adapters/google-tool-schema.ts:162-180, src/adapters/google-tool-schema.ts:194-227	The sanitizer shares traversal state across properties, items, and anyOf. It limits traversal to 1,024 nodes, prevents active $ref cycles, merges only supported keys, filters required names, and returns an empty schema when the root is exhausted.
Sanitizer boundary coverage tests/google-tool-schema.test.ts:4-14, tests/google-tool-schema.test.ts:346-372, tests/google-tool-schema.test.ts:374-391, tests/google-tool-schema.test.ts:393-413, tests/google-tool-schema.test.ts:415-428, tests/google-tool-schema.test.ts:430-453, tests/google-tool-schema.test.ts:455-479	Tests count sanitized nodes and verify repeated references, recursive references, shared-definition fan-out, wide property truncation, anyOf exhaustion, and budget exhaustion before array items traversal.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Possibly related PRs

• lidge-jun/opencodex#524: Both changes modify Google/Zen tool-schema sanitization, including $ref and recursive schema handling.

Suggested reviewers: hayderncenterpoint, lidge-jun

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: bounding Google tool schema expansion.

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• Create PR with unit tests

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[github-actions]

✅ READY

• all PR quality gates passed; the review readiness checklist is complete.

Review readiness checklist

• ✅ All CI tests are green on my local testing.
• ✅ I pushed my PR to the latest dev commit.
• ✅ I resolved all correct Codex and CodeRabbit findings.
• ✅ My PR is ready for review.

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Maintainers notified: @lidge-jun @Ingwannu @Wibias

[luvs01]

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@src/adapters/google-tool-schema.ts`:
- Around line 141-150: Bound property-key enumeration in the schema sanitization
function before the `for...in` loop over `value`: obtain only up to the allowed
`state.remainingNodes` keys, and return or stop without materializing the full
key list when the limit is exceeded. Apply the same bound before creating
`properties` entries or calling `sanitizeSchema`, while preserving own-property
filtering and budget-exhaustion behavior.

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📥 Commits

Reviewing files that changed from the base of the PR and between 4f746d1 and ad7ed6b.

📒 Files selected for processing (2)

• src/adapters/google-tool-schema.ts
• tests/google-tool-schema.test.ts

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[Wibias]

Thanks for the focused hardening here. The bounded schema-node budget, cycle-aware $ref handling, supported-key-only merge path, and regression coverage make this a strong fix for the expansion/DoS edge cases without widening scope. Exact-head Cross-platform CI and React Doctor are green. Merged — thank you!