Responses API

OpenAI-Compatible Responses API

Responses API is useful for newer agent-style clients and models that support the OpenAI Responses wire format. Confirm support before choosing it for a tool.

Who this is for

Developers configuring newer clients such as modern Codex flows.

Configuration reference

Values to confirm before setup

Responses endpoint family

Check the official Responses API compatibility page

Codex wire API

responses for supported models; chat for older chat-completion-only models

Setup flow

Practical steps

  1. 01Confirm the selected model supports Responses API.
  2. 02Use the documented Responses-compatible endpoint.
  3. 03Configure the client wire protocol as `responses` if the tool requires an explicit setting.
  4. 04Test a single prompt, then test conversation continuation if needed.
  5. 05Fall back to Chat Completions if the model or tool does not support Responses.

When to use it

Use Responses API when the client or model specifically benefits from it, such as newer agent workflows. Do not enable it just because the name sounds newer.

Quote note

The written quote should name the API protocol because tool support, model selection, and troubleshooting depend on it.

Common mistakes

Check these before escalating

  • Responses-compatible endpoint paths can differ from Chat Completions paths.
  • A tool configured for `responses` may fail against a chat-only model.
  • The model list changes, so verify before delivery.

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