xai/grok-4.1-fast-reasoning idGrok 4.1 Fast is xAI's best tool-calling model with a 2M context window. It reasons and completes agentic tasks accurately and rapidly, excelling at complex real-world use cases such as customer support and finance. To optimize for maximal intelligence use this variant. Otherwise, use the non-reasoning version.
# Drop-in OpenAI-compatible client$ import { generateText } from 'ai'$$ const { text } = await generateText({$ model: 'xai/grok-4.1-fast-reasoning',$ baseURL: 'https://synapse.garden/api/v1',$ apiKey: process.env.MG_KEY,$ prompt: 'Why is the sky blue?',$ })
| Rate | Per million tokens · USD |
|---|---|
| Input | $0.220/M |
| Output | $0.550/M |
| Cache read | $0.055/M |
Use the OpenAI or Anthropic SDK and point baseURL at https://synapse.garden/api/v1. Set model: ‘xai/grok-4.1-fast-reasoning’ and supply your Synapse Garden API key. No code changes beyond the base URL.
Input: $0.220/M per million tokens. Output: $0.550/M per million tokens. The free tier includes a million tokens every month at no cost.
grok-4.1-fast-reasoning supports a context window of 2M tokens, with a maximum output of 30K tokens.
No. Synapse Garden is the single API surface — one key gives you OpenAI, Anthropic, Google, Meta, Mistral, DeepSeek, xAI, Cohere, and more. Billing, rate limits, and audit logs are unified.
Sign up, create a key, drop our base URL into your existing client. The free tier includes a million tokens every month — no credit card.