# OpenResponses API now supported on Vercel AI Gateway

**Published:** January 15, 2026 | **Authors:** Walter Korman, Rohan Taneja, Jerilyn Zheng

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Vercel AI Gateway is a day 0 launch partner for the OpenResponses API, an open-source specification from OpenAI for multi-provider AI interactions.

OpenResponses provides a unified interface for text generation, streaming, tool calling, image input, and reasoning across providers.

**AI Gateway supports OpenResponses for:**

- **Text generation:** Send messages and receive responses from any supported model.
- **Streaming:** Receive tokens as they're generated via server-sent events.
- **Tool calling:** Define functions that models can invoke with structured arguments.
- **Image input:** Send images alongside text for vision-capable models.
- **Reasoning:** Enable extended thinking with configurable effort levels.
- **Provider fallbacks:** Configure automatic fallback chains across models and providers.

Use OpenResponses with your AI Gateway key, and switch models across providers by changing the model string.

```typescript
const response = await fetch('https://ai-gateway.vercel.sh/v1/responses', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    Authorization: `Bearer ${process.env.VERCEL_AI_GATEWAY_KEY}`,
  },
  body: JSON.stringify({
    model: 'anthropic/claude-sonnet-4.5',
    input: [
      {
        type: 'message',
        role: 'user',
        content: 'Explain quantum computing in one sentence.',
      }
    ],
  }),
});
```

You can also use OpenResponses for more complex cases, like tool calling.

```typescript
const response = await fetch('https://ai-gateway.vercel.sh/v1/responses', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    Authorization: `Bearer ${process.env.VERCEL_AI_GATEWAY_KEY}`,
  },
  body: JSON.stringify({
    model: 'zai/glm-4.7',
    input: [{ type: 'message', role: 'user', content: 'What is the weather in SF?' }],
    tools: [{
      type: 'function',
      name: 'get_weather',
      description: 'Get current weather for a location',
      parameters: {
        type: 'object',
        properties: { location: { type: 'string' } },
        required: ['location'],
      },
    }],
  }),
});
```

Read the [OpenResponses API documentation](https://vercel.com/docs/ai-gateway/openresponses) or [view the specification](https://www.openresponses.org/specification).

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📚 **More updates:** [View all changelog entries](/changelog/sitemap.md) | [Blog](/blog/sitemap.md)