API Compatibility

TrustedRails API keys provide OpenAI-compatible access through the proxy. This page documents what is currently supported.

Base URL

https://proxy.trustedrails.com/v1

Supported endpoints

| Endpoint | Status | |---|---| | POST /chat/completions | Supported | | POST /completions | Supported (legacy) | | GET /models | Supported | | GET /test-auth | Supported — returns key status and current rate limit |

Chat Completions parameters

The following parameters are supported in /v1/chat/completions requests:

| Parameter | Supported | |---|---| | model | Yes | | messages | Yes | | temperature | Yes | | top_p | Yes | | max_tokens | Yes | | stream | Yes | | stop | Yes | | presence_penalty | Yes | | frequency_penalty | Yes | | tools | Yes | | tool_choice | Yes | | thinking | Yes (model-dependent) |

Thinking (extended reasoning)

Models that support extended thinking (such as Qwen3) accept the thinking parameter:

{
  "model": "Qwen/Qwen3-235B-A22B-Instruct-2507-FP8",
  "messages": [{"role": "user", "content": "Solve this step by step: 23 * 47"}],
  "thinking": {"type": "enabled", "budget_tokens": 4096}
}

To disable thinking on models that enable it by default:

{
  "thinking": {"type": "disabled"}
}

Whether thinking is supported depends on the specific model. The parameter is passed through to the network as-is.

Message content format

The content field in messages supports both formats:

• String — plain text value ("content": "Hello")
• Array — structured content parts ("content": [{"type": "text", "text": "Hello"}])

Both formats are fully supported. However, only text content parts are available — image and other multimodal content types are not supported.

Response format

Responses follow the OpenAI Chat Completions response format:

• id — unique response identifier
• object — "chat.completion"
• choices — array of completion choices
• usage — token usage statistics (prompt_tokens, completion_tokens, total_tokens)

Streaming responses use Server-Sent Events (SSE), matching the OpenAI streaming format. The final chunk of every stream includes a usage object with token counts.

Note

The proxy strips non-standard fields from responses (such as provider-specific metadata) to maintain strict OpenAI compatibility. Only standard OpenAI response fields are returned.

Request processing

The proxy applies the following processing to your requests:

• Standard OpenAI defaults are applied for omitted parameters (e.g., temperature: 0.7)
• max_tokens is clamped to the model's maximum output length
• Multimodal content (image inputs) is not supported — only text content parts are accepted

Not yet supported

The following OpenAI features are not currently available:

• Responses API (/v1/responses)
• Embeddings API
• Images API
• Audio API (TTS, STT)
• Assistants API
• Fine-tuning API
• Vision (image inputs)
• JSON mode / structured outputs

These may be added in future releases. Check back for updates.