# ![OpenCode Go logo](https://models.dev/logos/opencode-go.svg)OpenCode Go

Access 14 OpenCode Go models through Mastra's model router. Authentication is handled automatically using the `OPENCODE_API_KEY` environment variable.

Learn more in the [OpenCode Go documentation](https://opencode.ai/docs/zen).

```bash
OPENCODE_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: "opencode-go/deepseek-v4-flash"
});

// 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 [OpenCode Go documentation](https://opencode.ai/docs/zen) for details.

## Models

| Model                           | Context | Tools | Reasoning | Image | Audio | Video | Input $/1M | Output $/1M |
| ------------------------------- | ------- | ----- | --------- | ----- | ----- | ----- | ---------- | ----------- |
| `opencode-go/deepseek-v4-flash` | 1.0M    |       |           |       |       |       | $0.14      | $0.28       |
| `opencode-go/deepseek-v4-pro`   | 1.0M    |       |           |       |       |       | $2         | $3          |
| `opencode-go/glm-5`             | 203K    |       |           |       |       |       | $1         | $3          |
| `opencode-go/glm-5.1`           | 203K    |       |           |       |       |       | $1         | $4          |
| `opencode-go/kimi-k2.5`         | 262K    |       |           |       |       |       | $0.60      | $3          |
| `opencode-go/kimi-k2.6`         | 262K    |       |           |       |       |       | $0.32      | $1          |
| `opencode-go/mimo-v2-omni`      | 262K    |       |           |       |       |       | $0.40      | $2          |
| `opencode-go/mimo-v2-pro`       | 1.0M    |       |           |       |       |       | $1         | $3          |
| `opencode-go/mimo-v2.5`         | 1.0M    |       |           |       |       |       | $0.40      | $2          |
| `opencode-go/mimo-v2.5-pro`     | 1.0M    |       |           |       |       |       | $1         | $3          |
| `opencode-go/minimax-m2.5`      | 205K    |       |           |       |       |       | $0.30      | $1          |
| `opencode-go/minimax-m2.7`      | 205K    |       |           |       |       |       | $0.30      | $1          |
| `opencode-go/qwen3.5-plus`      | 262K    |       |           |       |       |       | $0.20      | $1          |
| `opencode-go/qwen3.6-plus`      | 262K    |       |           |       |       |       | $0.50      | $3          |

## Advanced configuration

### Custom headers

```typescript
const agent = new Agent({
  id: "custom-agent",
  name: "custom-agent",
  model: {
    url: "https://opencode.ai/zen/go/v1",
    id: "opencode-go/deepseek-v4-flash",
    apiKey: process.env.OPENCODE_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
      ? "opencode-go/qwen3.6-plus"
      : "opencode-go/deepseek-v4-flash";
  }
});
```