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xAI logoxAI

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);
}

Models

ModelImageAudioVideoToolsStreamingContext Window
xai/grok-4-fast-non-reasoning2,000,000
xai/grok-3-fast131,072
xai/grok-4256,000
xai/grok-2-vision8,192
xai/grok-code-fast-1256,000
xai/grok-2131,072
xai/grok-3-mini-fast-latest131,072
xai/grok-2-vision-12128,192
xai/grok-3131,072
xai/grok-4-fast2,000,000
xai/grok-2-latest131,072
xai/grok-2-1212131,072
xai/grok-3-fast-latest131,072
xai/grok-3-latest131,072
xai/grok-2-vision-latest8,192
xai/grok-vision-beta8,192
xai/grok-3-mini131,072
xai/grok-beta131,072
xai/grok-3-mini-latest131,072
xai/grok-3-mini-fast131,072

Advanced Configuration

Custom Headers

const agent = new Agent({
name: "custom-agent",
model: {
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-vision-beta" : "xai/grok-2";
},
});

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