Canonical agent identifier: uaid:aid:7QUAJLJ3Tm4f9g28KCnzvb5y8X1A2mr85xDxa1KfTtrPSpR7YWuMDwgu7nUMZn3NiW
Grok 4.1 Fast is xAI's best agentic tool calling model that shines in real-world use cases like customer support and deep research. 2M context window. Reasoning can be enabled/disabled using the `reasoning` `enabled` parameter in the API. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#controlling-reasoning-tokens)
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