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);
}

Models

20 available models

Model	Context	Tools	Reasoning	Image	Audio	Video	Input $/1M	Output $/1M
xai/grok-2	131K						$2	$10
xai/grok-2-1212	131K						$2	$10
xai/grok-2-latest	131K						$2	$10
xai/grok-2-vision	8K						$2	$10
xai/grok-2-vision-1212	8K						$2	$10
xai/grok-2-vision-latest	8K						$2	$10
xai/grok-3	131K						$3	$15
xai/grok-3-fast	131K						$5	$25
xai/grok-3-fast-latest	131K						$5	$25
xai/grok-3-latest	131K						$3	$15
xai/grok-3-mini	131K						$0.30	$0.50
xai/grok-3-mini-fast	131K						$0.60	$4
xai/grok-3-mini-fast-latest	131K						$0.60	$4
xai/grok-3-mini-latest	131K						$0.30	$0.50
xai/grok-4	256K						$3	$15
xai/grok-4-fast	2.0M						$0.20	$0.50
xai/grok-4-fast-non-reasoning	2.0M						$0.20	$0.50
xai/grok-beta	131K						$5	$15
xai/grok-code-fast-1	256K						$0.20	$2
xai/grok-vision-beta	8K						$5	$15

Advanced Configuration

Custom Headers

const agent = new Agent({
  name: "custom-agent",
  model: {
    id: "xai/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";
  }
});

Provider Options

xAI supports the following provider-specific options via the providerOptions parameter:

const response = await agent.generate("Hello!", {
  providerOptions: {
    xai: {
      // See available options in the table below
    }
  }
});

Available Options

reasoningEffort?:

"low" | "high" | undefined

searchParameters?:

{ mode: "off" | "auto" | "on"; returnCitations?: boolean | undefined; fromDate?: string | undefined; toDate?: string | undefined; maxSearchResults?: number | undefined; sources?: ({ ...; } | ... 2 more ... | { ...; })[] | undefined; } | undefined

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

For detailed provider-specific documentation, see the AI SDK xAI provider docs.