> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pipellm.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Responses

> OpenAI-compatible Responses API on PipeLLM

For authentication and model list, see [Overview](/api-reference/openai/overview).

## Endpoint

```
POST https://api.pipellm.ai/v1/responses
```

<Note>
  This free route accepts OpenAI Responses requests and routes only to
  OpenAI-compatible platforms. Cross-protocol routing for the Responses API is
  not available yet. If you need cross-protocol routing today, use the
  [OpenAI Format Converter](/converter/openai-format) with Chat Completions.
</Note>

## Code Examples

<Tabs>
  <Tab title="cURL">
    ```bash theme={null}
    curl https://api.pipellm.ai/v1/responses \
      -H "Content-Type: application/json" \
      -H "Authorization: Bearer $PIPELLM_API_KEY" \
      -d '{
        "model": "gpt-4.1",
        "input": "Write a one-sentence explanation of why the sky is blue."
      }'
    ```
  </Tab>

  <Tab title="Python">
    ```python theme={null}
    import os
    from openai import OpenAI

    client = OpenAI(
      api_key=os.getenv("PIPELLM_API_KEY"),
      base_url="https://api.pipellm.ai/v1"
    )

    response = client.responses.create(
      model="gpt-4.1",
      input="Write a one-sentence explanation of why the sky is blue."
    )

    print(response.output_text)
    ```
  </Tab>

  <Tab title="TypeScript">
    ```typescript theme={null}
    import OpenAI from "openai";

    const client = new OpenAI({
      apiKey: process.env.PIPELLM_API_KEY,
      baseURL: "https://api.pipellm.ai/v1",
    });

    const response = await client.responses.create({
      model: "gpt-4.1",
      input: "Write a one-sentence explanation of why the sky is blue.",
    });

    console.log(response.output_text);
    ```
  </Tab>
</Tabs>

## Common Request Fields

| Field               | Type            | Required | Description                     |
| ------------------- | --------------- | -------- | ------------------------------- |
| `model`             | string          | Yes      | OpenAI-compatible model ID      |
| `input`             | string or array | Yes      | Text or structured input items  |
| `instructions`      | string          | No       | Developer or system instruction |
| `stream`            | boolean         | No       | Enable streaming output         |
| `tools`             | array           | No       | Built-in or custom tools        |
| `temperature`       | number          | No       | Sampling temperature            |
| `max_output_tokens` | integer         | No       | Maximum output tokens           |

## Response Shape

```json theme={null}
{
  "id": "resp_123",
  "object": "response",
  "model": "gpt-4.1",
  "output": [
    {
      "type": "message",
      "role": "assistant",
      "content": [
        {
          "type": "output_text",
          "text": "The atmosphere scatters blue light more strongly than red light."
        }
      ]
    }
  ]
}
```

## Related Docs

<Columns cols={3}>
  <Card title="Routing & Protocols" icon="route" href="/guides/routing-protocols">
    Understand native route constraints
  </Card>

  <Card title="OpenAI Overview" icon="bolt" href="/api-reference/openai/overview">
    OpenAI-compatible endpoints on PipeLLM
  </Card>

  <Card title="OpenAI Migration Guide" icon="book" href="https://platform.openai.com/docs/guides/responses-vs-chat-completions">
    Official guidance on Responses vs Chat Completions
  </Card>
</Columns>