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

# Claude OpenAI-Compatible Chat

> Claude Chat Completions compatibility path verified against Crazyrouter production on 2026-03-23

> Last updated: 2026-06-06

# Claude OpenAI-Compatible Chat

```
POST /v1/chat/completions
```

As of March 23, 2026, Crazyrouter production has verified:

* non-stream `claude-opus-4-8` requests return `object: "chat.completion"`
* the current `message` reliably includes `role` and `content`
* streaming requests return `chat.completion.chunk`
* the SSE stream still ends with `data: [DONE]`

***

## Non-Streaming Request

```bash theme={null}
curl https://api.crazyrouter.com/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "claude-opus-4-8",
    "messages": [
      {"role": "system", "content": "You are a concise assistant."},
      {"role": "user", "content": "Compare PostgreSQL and MySQL in one paragraph."}
    ],
    "max_tokens": 256,
    "temperature": 0.2
  }'
```

Observed response shape:

```json theme={null}
{
  "object": "chat.completion",
  "model": "claude-opus-4-8",
  "choices": [
    {
      "message": {
        "role": "assistant",
        "content": "PostgreSQL and MySQL are both popular..."
      }
    }
  ]
}
```

***

## Streaming Request

```bash theme={null}
curl https://api.crazyrouter.com/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "claude-opus-4-8",
    "messages": [
      {"role": "user", "content": "Say hello in one sentence."}
    ],
    "max_tokens": 128,
    "stream": true
  }'
```

The 2026-03-23 production streaming probe began like this:

```text theme={null}
data: {"object":"chat.completion.chunk","model":"claude-opus-4-8","choices":[{"delta":{"role":"assistant"}}]}
data: {"object":"chat.completion.chunk","model":"claude-opus-4-8","choices":[{"delta":{"content":"Hello! ..."}}]}
data: [DONE]
```

<Note>
  If you need Claude-native `thinking`, native tool blocks, or document inputs, prefer [Claude Messages](/chat/anthropic/messages).
</Note>