xAI
Access 20 xAI models through Mastra’s model router. Authentication is handled automatically using the XAI_API_KEY
environment variable.
Learn more in the xAI documentation .
XAI_API_KEY=your-api-key
import { Agent } from "@mastra/core";
const agent = new Agent({
name: "my-agent",
instructions: "You are a helpful assistant",
model: "xai/grok-2"
});
// Generate a response
const response = await agent.generate("Hello!");
// Stream a response
const stream = await agent.stream("Tell me a story");
for await (const chunk of stream) {
console.log(chunk);
}
Mastra uses the OpenAI-compatible /chat/completions
endpoint. Some provider-specific features may not be available. Check the xAI documentation for details.
Models
Model | Context | Tools | Reasoning | Image | Audio | Video | Input $/1M | Output $/1M |
---|---|---|---|---|---|---|---|---|
xai/grok-4-fast-non-reasoning | 2.0M | $0.20 | $0.50 | |||||
xai/grok-3-fast | 131K | $5 | $25 | |||||
xai/grok-4 | 256K | $3 | $15 | |||||
xai/grok-2-vision | 8K | $2 | $10 | |||||
xai/grok-code-fast-1 | 256K | $0.20 | $2 | |||||
xai/grok-2 | 131K | $2 | $10 | |||||
xai/grok-3-mini-fast-latest | 131K | $0.60 | $4 | |||||
xai/grok-2-vision-1212 | 8K | $2 | $10 | |||||
xai/grok-3 | 131K | $3 | $15 | |||||
xai/grok-4-fast | 2.0M | $0.20 | $0.50 | |||||
xai/grok-2-latest | 131K | $2 | $10 | |||||
xai/grok-2-1212 | 131K | $2 | $10 | |||||
xai/grok-3-fast-latest | 131K | $5 | $25 | |||||
xai/grok-3-latest | 131K | $3 | $15 | |||||
xai/grok-2-vision-latest | 8K | $2 | $10 | |||||
xai/grok-vision-beta | 8K | $5 | $15 | |||||
xai/grok-3-mini | 131K | $0.30 | $0.50 | |||||
xai/grok-beta | 131K | $5 | $15 | |||||
xai/grok-3-mini-latest | 131K | $0.30 | $0.50 | |||||
xai/grok-3-mini-fast | 131K | $0.60 | $4 |
Advanced Configuration
Custom Headers
const agent = new Agent({
name: "custom-agent",
model: {
url: "https://api.x.ai/v1/chat/completions",
modelId: "grok-2",
apiKey: process.env.XAI_API_KEY,
headers: {
"X-Custom-Header": "value"
}
}
});
Dynamic Model Selection
const agent = new Agent({
name: "dynamic-agent",
model: ({ runtimeContext }) => {
const useAdvanced = runtimeContext.task === "complex";
return useAdvanced
? "xai/grok-2"
: "xai/grok-2-1212";
}
});
Direct Provider Installation
This provider can also be installed directly as a standalone package, which can be used instead of the Mastra model router string. View the package documentation for more details.
npm install @ai-sdk/xai