[rosetta-livekit-bot]

Summary

Port livekit/agents#7511 to fall back from forced Anthropic tool choices to auto for Claude Opus 5.5, Sonnet 5.5, Fable 5.1, and Mythos 5.1. Preserve disable_parallel_tool_use when configured and warn once per LLM instance.

Source diff coverage

Source diff coverage

• Adapted: livekit-plugins/livekit-plugins-anthropic/livekit/plugins/anthropic/llm.py -> plugins/anthropic/src/llm.ts. Ported all unsupported-model prefixes, the per-instance warning guard, forced any/named-tool fallback to auto, preservation of disable_parallel_tool_use, and model logging metadata using the target Pino API.
• Adapted: tests/test_plugin_anthropic_request.py -> plugins/anthropic/src/llm.test.ts. Ported both request-level tests into the existing Vitest counterpart with a mocked Anthropic client. Test fixtures explicitly unset the JS-specific default parallelToolCalls: true where the Python source tests exercise the omitted-option case; the explicit false case remains covered.
• Not applicable: none. Every source file has a target counterpart and was ported. No supporting infrastructure is missing.

Authoritative source: livekit/agents#7511

Validation

• pnpm test plugins/anthropic (17 passed)
• pnpm --filter @livekit/agents-plugin-anthropic build
• pnpm --filter @livekit/agents-plugin-anthropic lint
• pnpm exec prettier --check plugins/anthropic/src/llm.ts plugins/anthropic/src/llm.test.ts .changeset/anthropic-auto-tool-choice.md
• pnpm build (42 workspace tasks passed)
• pnpm lint (fails on 307 pre-existing findings in unrelated files; the Anthropic package lint passes)

---

Ported from livekit/agents#7511

Original PR description

Problem

LLM.chat() translates a forced tool_choice the same way for every model: "required" becomes {"type": "any"} and a named function becomes {"type": "tool", "name": ...}. Claude Opus 5.5, Sonnet 5.5, Fable 5.1 and Mythos 5.1 don't support forced tool use (Opus 5.5, Sonnet 5.5, Fable 5.1 and Mythos 5.1 migration guides), so on these models every such request fails with a 400: tool_choice: type "tool" and "any" are not supported for this model. AMD and keyterm detection force "required" on their own, so they fail on these models even when the app never sets a tool choice.

Changes

For these four models a forced choice is now sent as {"type": "auto"}, keeping disable_parallel_tool_use when it's set, and the plugin logs a warning once per LLM instance. Requests for all other models are unchanged. These models have no forced mode, so the model may now answer without calling a tool, or call a different tool than the one named.

[changeset-bot]

🦋 Changeset detected

Latest commit: 10d0f8b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 41 packages

Name	Type
@livekit/agents-plugin-anthropic	Patch
@livekit/agents	Patch
@livekit/agents-plugin-anam	Patch
@livekit/agents-plugin-assemblyai	Patch
@livekit/agents-plugin-azure	Patch
@livekit/agents-plugin-baseten	Patch
@livekit/agents-plugin-bey	Patch
@livekit/agents-plugin-cartesia	Patch
@livekit/agents-plugin-cerebras	Patch
@livekit/agents-plugin-deepgram	Patch
@livekit/agents-plugin-did	Patch
@livekit/agents-plugin-elevenlabs	Patch
@livekit/agents-plugin-fishaudio	Patch
@livekit/agents-plugin-google	Patch
@livekit/agents-plugin-hume	Patch
@livekit/agents-plugin-inworld	Patch
@livekit/agents-plugin-krisp	Patch
@livekit/agents-plugin-lemonslice	Patch
@livekit/agents-plugin-liveavatar	Patch
@livekit/agents-plugin-livekit	Patch
@livekit/agents-plugin-meta	Patch
@livekit/agents-plugin-minimax	Patch
@livekit/agents-plugin-mistral	Patch
@livekit/agents-plugin-mistralai	Patch
@livekit/agents-plugin-neuphonic	Patch
@livekit/agents-plugin-openai	Patch
@livekit/agents-plugin-perplexity	Patch
@livekit/agents-plugin-phonic	Patch
@livekit/agents-plugin-protoface	Patch
@livekit/agents-plugin-resemble	Patch
@livekit/agents-plugin-rime	Patch
@livekit/agents-plugin-runway	Patch
@livekit/agents-plugin-sarvam	Patch
@livekit/agents-plugin-silero	Patch
@livekit/agents-plugin-soniox	Patch
@livekit/agents-plugin-speechify	Patch
@livekit/agents-plugin-synthesia	Patch
@livekit/agents-plugin-tavus	Patch
@livekit/agents-plugins-test	Patch
@livekit/agents-plugin-trugen	Patch
@livekit/agents-plugin-xai	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR