fix(session): settle pending tool calls on schema errors

[codeg-dev]

Issue for this PR

Closes#30093

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Settles a pending tool part to error when the stream later emits a matching schema-validation tool-error. This covers malformed built-in tool calls such as bash with an empty object, while preserving empty objects for tools that have no required args.

Prepared with AI assistance.

How did you verify your code works?

• bun run typecheck
• git diff --check
• LSP diagnostics clean for packages/opencode/src/session/processor.ts and packages/opencode/src/session/retry.ts
• Built and installed a custom binary on private host: opencode --version -> 1.15.13-empty-tool-validation
• Runtime smoke with a mock OpenAI-compatible provider emitted malformed bash empty-object args; exported session local session recorded the bash tool part as status error, not pending.

Focused tests are blocked in this worktree by an existing fixture issue: both the new processor test and unrelated test/provider/header-timeout.test.ts fail before assertions with ProviderModelNotFoundError for test/test-model.

Screenshots / recordings

Not a UI change.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[github-actions]

Thanks for your contribution!

This PR doesn't have a linked issue. All PRs must reference an existing issue.

Please:

1. Open an issue describing the bug/feature (if one doesn't exist)
2. Add Fixes #<number> or Closes #<number> to this PR description

See CONTRIBUTING.md for details.

[codeg-dev]

Runtime smoke verified on private host with custom binary 1.15.13-empty-tool-validation: mock provider emitted malformed bash empty-object args; exported session local session shows the bash tool part settled as status error, not pending.

[github-actions]

Thanks for updating your PR! It now meets our contributing guidelines. 👍

[codeg-dev]

Additional v1.16.2 verification update:

• Re-applied the pending/running tool settlement change in a focused custom artifact: 1.16.2-codeg.20260606.
• macOS artifact SHA-256: cde7462823cbb639b7f9b09a757699c1e983a9b650e79eae3a6d7025643d295b.
• Windows x64 artifact SHA-256: 2496173eaf3005078dbcb3fbccc626219365f69848931d308a53f793c94021b3.
• Verified openai/gpt-5.5 tool-failure recovery after a failing bash false call on private host, private host, private host, and codeg-hq.
• Sentinels observed: MTB_CUSTOM_GPT55_TOOL_FAILURE_DONE, FOB_NOTEBOOKLM_DISABLED_TOOL_DONE, OPS_CUSTOM_GPT55_TOOL_DONE, and HQ_CUSTOM_GPT55_TOOL_DONE.

This confirms the issue remains relevant on top of v1.16.2 and the patch still resolves the pending/running tool-call settlement path without changing the selected model.

[codeg-dev]

Rebased onto latest dev and force-pushed. CI is green (check-compliance ✅, check-standards ✅). Ready for review — this PR was 295 commits behind so the refresh should help avoid future merge conflicts. Thanks!

[mikeatlas]

bump

[codeg-dev]

AI-assisted verification update (2026-06-09 KST): I cherry-picked this PR onto the current OpenCode 1.16.2 baseline for our local custom artifact 1.16.2-codeg.20260609-omo481.

Verified:

• macOS darwin-arm64 build/typecheck completed for the custom artifact.
• Windows x64 single-binary artifact launched successfully on Windows 11.
• Windows smoke: opencode --version, opencode serve, /agent, /skill, /command, /session, and embedded web UI root all passed.
• Embedded web UI fingerprint matched the official binary UI assets (/assets/index-B36vrVAZ.js, /assets/index-ksHcXe9H.css), with no hosted SPA fallback involved.

No regression observed in this local cross-platform smoke pass.

[github-actions]

Automated PR Cleanup

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