Baseten

Access 2 Baseten models through Mastra's model router. Authentication is handled automatically using the BASETEN_API_KEY environment variable.

Learn more in the Baseten documentation.

BASETEN_API_KEY=your-api-key

import { Agent } from "@mastra/core";

const agent = new Agent({
  name: "my-agent",
  instructions: "You are a helpful assistant",
  model: "baseten/Qwen3/Qwen3-Coder-480B-A35B-Instruct",
});

// 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);
}

OpenAI Compatibility

Mastra uses the OpenAI-compatible /chat/completions endpoint. Some provider-specific features may not be available. Check the Baseten documentation for details.

Models

Model	Image	Audio	Video	Tools	Streaming	Context Window
baseten/moonshotai/Kimi-K2-Instruct-0905	✗	✗	✗	✓	✗	262,144
baseten/Qwen3/Qwen3-Coder-480B-A35B-Instruct	✗	✗	✗	✓	✗	262,144

Advanced Configuration

Custom Headers

const agent = new Agent({
  name: "custom-agent",
  model: {
    url: "https://inference.baseten.co/v1",
    modelId: "Qwen3/Qwen3-Coder-480B-A35B-Instruct",
    apiKey: process.env.BASETEN_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
      ? "baseten/moonshotai/Kimi-K2-Instruct-0905"
      : "baseten/Qwen3/Qwen3-Coder-480B-A35B-Instruct";
  },
});