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

# Chat API

> Call ChatGPT, Claude, Gemini, and Responses through one Base URL.

# Chat API

Omniall AI exposes multiple chat-style protocols on **`https://api.omniall.ai`**. Pick model IDs from the [Model Square](https://omniall.ai/pricing).

| Protocol | Method | Path | Notes |
| - | - | - | - |
| Chat Completions | `POST` | `/v1/chat/completions` | OpenAI-compatible; streaming supported |
| Claude Messages | `POST` | `/v1/messages` | Anthropic Messages shape |
| Gemini | `POST` | `/v1beta/models/{model}:generateContent` | Native Gemini; also `streamGenerateContent` |
| Responses | `POST` | `/v1/responses` | OpenAI Responses API |

Auth: `Authorization: Bearer sk-...` (Claude may also use `x-api-key`; Gemini may use `x-goog-api-key`).

## Quick example (Chat Completions)

```bash theme={null}
curl https://api.omniall.ai/v1/chat/completions \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-4o-mini",
    "messages": [{"role": "user", "content": "Hello"}]
  }'
```

Full schemas and playgrounds: **API Reference → Chat**.


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