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

# Chat Completions

> Create OpenAI-compatible chat completion responses with Confidential AI models.

## Endpoint

```bash theme={"system"}
POST https://api.redpill.ai/v1/chat/completions
```

Creates a response for a chat conversation. Use the same OpenAI-compatible request shape you already use with the OpenAI SDK, then set the base URL to `https://api.redpill.ai/v1`.

## Request Body

<ParamField body="model" type="string" required>
  Model ID to use for completion.

  Examples: `phala/qwen3.5-27b`, `phala/gemma-3-27b-it`, `z-ai/glm-5`, `openai/gpt-oss-120b`.
</ParamField>

<ParamField body="messages" type="array" required>
  Conversation messages. Each message includes `role` and `content`.

  ```json theme={"system"}
  [
    {"role": "system", "content": "You are a helpful assistant."},
    {"role": "user", "content": "Explain GPU TEE in one paragraph."}
  ]
  ```
</ParamField>

<ParamField body="temperature" type="number">
  Sampling temperature. Typical range is `0` to `2`.
</ParamField>

<ParamField body="max_tokens" type="integer">
  Maximum number of output tokens for most open models and GPU TEE models.
</ParamField>

<ParamField body="max_completion_tokens" type="integer">
  Maximum output tokens for newer OpenAI reasoning models that do not accept `max_tokens`.
</ParamField>

<ParamField body="stream" type="boolean">
  Set to `true` to receive server-sent event chunks.
</ParamField>

<ParamField body="tools" type="array">
  Function/tool definitions that supported models can call.
</ParamField>

<ParamField body="tool_choice" type="string | object">
  Controls whether the model may call tools. Common values are `auto`, `none`, or a specific tool selection object.
</ParamField>

<ParamField body="response_format" type="object">
  Requests structured output from supported models, including JSON schema mode.
</ParamField>

## Examples

<CodeGroup>
  ```bash cURL theme={"system"}
  curl https://api.redpill.ai/v1/chat/completions \
    -H "Content-Type: application/json" \
    -H "Authorization: Bearer <API_KEY>" \
    -d '{
      "model": "phala/qwen3.5-27b",
      "messages": [
        {"role": "user", "content": "What privacy guarantees does GPU TEE provide?"}
      ]
    }'
  ```

  ```python Python theme={"system"}
  from openai import OpenAI

  client = OpenAI(
      api_key="<API_KEY>",
      base_url="https://api.redpill.ai/v1",
  )

  response = client.chat.completions.create(
      model="phala/qwen3.5-27b",
      messages=[
          {"role": "user", "content": "What privacy guarantees does GPU TEE provide?"}
      ],
  )

  print(response.choices[0].message.content)
  ```

  ```typescript TypeScript theme={"system"}
  import OpenAI from "openai";

  const client = new OpenAI({
    apiKey: "<API_KEY>",
    baseURL: "https://api.redpill.ai/v1",
  });

  const response = await client.chat.completions.create({
    model: "phala/qwen3.5-27b",
    messages: [
      { role: "user", content: "What privacy guarantees does GPU TEE provide?" },
    ],
  });

  console.log(response.choices[0].message.content);
  ```
</CodeGroup>

## Response

```json theme={"system"}
{
  "id": "chatcmpl-123",
  "object": "chat.completion",
  "created": 1677652288,
  "model": "phala/qwen3.5-27b",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "GPU TEE protects inference by..."
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 16,
    "completion_tokens": 48,
    "total_tokens": 64
  }
}
```

The `id` field is the request ID. Use it with [Request Signature](/phala-cloud/confidential-ai/confidential-model/api-reference/signature) when you need cryptographic proof for this specific response.

## Feature Notes

* Streaming uses the same `stream: true` option as the OpenAI API.
* Vision models accept multimodal `content` arrays with `image_url` entries.
* Tool calling uses OpenAI-compatible `tools`, `tool_choice`, assistant `tool_calls`, and tool response messages.
* Structured output uses `response_format` on supported models.

## Next Steps

<CardGroup cols={2}>
  <Card title="List Models" icon="list" href="/phala-cloud/confidential-ai/confidential-model/api-reference/models">
    Discover available Confidential AI models and capabilities
  </Card>

  <Card title="Verify Responses" icon="signature" href="/phala-cloud/confidential-ai/confidential-model/api-reference/signature">
    Fetch the signature for a chat completion response
  </Card>
</CardGroup>