Anthropic updated its API on October 5, 2026. The Models API now includes a new field called capabilities.thinking.types.disabled. When you call GET /v1/models or GET /v1/models/{model_id}, the response tells you if a model has thinking turned off (type: "disabled"). This lets developers see at a glance which models can use the thinking feature.
Why it matters
Developers can now programmatically avoid models that have thinking disabled, preventing unexpected behavior in applications.