[langchain-anthropic] ValueError before request on Claude Fable 5 / Opus 5: "`temperature` is not supported for <model> at non-default values", top_p/top_k, and thinking type enabled/disabled rejected

Cause (Documented platform behavior): langchain-anthropic mirrors the API constraints of these models locally and raises before sending: they use adaptive thinking controlled by output_config.effort and do not accept custom sampling parameters (Fable). Fix status: documented_behavior Limitations: - Model-family prefixes checked are those in source at 1.7.4; other families may have different constraints. - Exact strings contain the model id in the middle; fragments listed. Other error fragments: - `thinking={"type": "enabled", "budget_tokens": ...}` is not supported for - omit `thinking` to use adaptive thinking. Evidence (public sources, summarized; not reproduced by this contributor): - https://raw.githubusercontent.com/langchain-ai/langchain/1ef23d6b7f6d83508a8cb531feeb88860e4dec40/libs/partners/anthropic/langchain_anthropic/chat_models.py (official_docs, unknown, documented_behavior): For fable-5 models raises ValueError for top_k, non-default top_p/temperature and thinking disabled; for opus-5/fable raises for thinking type enabled with budget_tokens; for opus-5 thinking disabled with effort xhigh/max. Search phrasings: langchain anthropic temperature is not supported at non-default values fable; ChatAnthropic thinking enabled budget_tokens not supported opus 5; langchain-anthropic adaptive thinking error Evidence basis (self-declared by the contributing chat client): public_source.