# ![FreeModel logo](https://models.dev/logos/freemodel.svg)FreeModel

Access 10 FreeModel models through Mastra's model router. Authentication is handled automatically using the `FREEMODEL_API_KEY` environment variable.

Learn more in the [FreeModel documentation](https://freemodel.dev).

```bash
FREEMODEL_API_KEY=your-api-key
```

```typescript
import { Agent } from "@mastra/core/agent";

const agent = new Agent({
  id: "my-agent",
  name: "My Agent",
  instructions: "You are a helpful assistant",
  model: "freemodel/claude-fable-5"
});

// 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);
}
```

> **Info:** Mastra uses the OpenAI-compatible `/chat/completions` endpoint. Some provider-specific features may not be available. Check the [FreeModel documentation](https://freemodel.dev) for details.

## Models

| Model                                 | Context | Tools | Reasoning | Image | Audio | Video | Input $/1M | Output $/1M |
| ------------------------------------- | ------- | ----- | --------- | ----- | ----- | ----- | ---------- | ----------- |
| `freemodel/claude-fable-5`            | 1.0M    |       |           |       |       |       | $10        | $50         |
| `freemodel/claude-haiku-4-5-20251001` | 200K    |       |           |       |       |       | $1         | $5          |
| `freemodel/claude-opus-4-6`           | 1.0M    |       |           |       |       |       | $5         | $25         |
| `freemodel/claude-opus-4-7`           | 1.0M    |       |           |       |       |       | $5         | $25         |
| `freemodel/claude-opus-4-8`           | 1.0M    |       |           |       |       |       | $5         | $25         |
| `freemodel/claude-sonnet-4-6`         | 1.0M    |       |           |       |       |       | $3         | $15         |
| `freemodel/gpt-5.3-codex`             | 400K    |       |           |       |       |       | $2         | $14         |
| `freemodel/gpt-5.4`                   | 1.1M    |       |           |       |       |       | $3         | $15         |
| `freemodel/gpt-5.4-mini`              | 400K    |       |           |       |       |       | $0.75      | $5          |
| `freemodel/gpt-5.5`                   | 1.1M    |       |           |       |       |       | $5         | $30         |

## Advanced configuration

### Custom headers

```typescript
const agent = new Agent({
  id: "custom-agent",
  name: "custom-agent",
  model: {
    url: "https://cc.freemodel.dev/v1",
    id: "freemodel/claude-fable-5",
    apiKey: process.env.FREEMODEL_API_KEY,
    headers: {
      "X-Custom-Header": "value"
    }
  }
});
```

### Dynamic model selection

```typescript
const agent = new Agent({
  id: "dynamic-agent",
  name: "Dynamic Agent",
  model: ({ requestContext }) => {
    const useAdvanced = requestContext.task === "complex";
    return useAdvanced
      ? "freemodel/gpt-5.5"
      : "freemodel/claude-fable-5";
  }
});
```

## 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](https://www.npmjs.com/package/@ai-sdk/anthropic) for more details.

**npm**:

```bash
npm install @ai-sdk/anthropic
```

**pnpm**:

```bash
pnpm add @ai-sdk/anthropic
```

**Yarn**:

```bash
yarn add @ai-sdk/anthropic
```

**Bun**:

```bash
bun add @ai-sdk/anthropic
```