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.
Responses API Overview
The Responses API is currently one of the main routes for newer GPT capabilities on Crazyrouter. This page only documents conclusions that were revalidated against production on2026-03-22.
In the current production-verified scope, Claude supports only
POST /v1/messages and POST /v1/chat/completions, not POST /v1/responses. Treat the Responses pages as GPT-first guidance.Current framing
- If you need inspectable reasoning output, prefer
/v1/responses - If you need OpenAI-style web search, prefer
/v1/responses - If you only need ordinary chat or want to keep an existing integration,
/v1/chat/completionsis still fine
Responses API vs Chat Completions API
| Dimension | Responses API | Chat Completions API |
|---|---|---|
| Endpoint | /v1/responses | /v1/chat/completions |
| Input shape | input | messages |
| Output shape | output[] item list | choices[].message |
| GPT reasoning | Verified reasoning item | reasoning_effort works, but reasoning_content is not stable |
| OpenAI-style web search | Verified web_search_preview path | The older web_search shape did not produce a stable verifiable trigger in this round |
| Streaming | Richer event types | Traditional delta SSE |
Smallest useful example
Python
When to prefer Responses
- You need
gpt-5.4reasoning summaries - You need to verify whether the model actually triggered
web_search_call - You want richer SSE events
When to keep Chat Completions
- You already have a stable Chat Completions integration
- You only care about the final answer, not the
reasoningitem - You are integrating Claude, Gemini, or other OpenAI-compatible models
Both APIs can coexist in the same project. In practice, the better pattern is usually not a full migration, but moving only the requests that need newer capabilities onto
/v1/responses.