X-Ai/Grok-4-Fast-Reasoning API
About
Build advanced reasoning agents with X-Ai/Grok-4-Fast-Reasoning, a specialized AI model optimized for complex logic and chain-of-thought tasks. This model delivers available completely free of charge, native tool calling support. Access X-Ai/Grok-4-Fast-Reasoning via the Qiniu API with up to 2.0M output tokens.
Capabilities
Input Modalities
textimageaudiovideo
Reasoning
Yes
Structured Output
No
Tool Use
Yes
WeightsClosed
Temperature
Adjustable
Attachment
Supported
Limits
Context Window
2.0M
Tokens
Input Limit
2.0M
Tokens
Max Output
2.0M
Tokens
Pricing
Standard (per 1M tokens)
Input
Free
Output
Free
Frequently Asked Questions
X-Ai/Grok-4-Fast-Reasoning by Qiniu costs Free per 1M input tokens and Free per 1M output tokens.
Model Details
API Integration
NPM Package
@ai-sdk/openai-compatible
Environment Variables
QINIU_API_KEY
API Base URL
https://api.qnaigc.com/v1