---
title: "Create an OpenAI-compatible response"
method: POST
path: "/ai/openai/responses"
tags: ["OpenAI Chat"]
---

# Create an OpenAI-compatible response

`POST /ai/openai/responses`

Create a response using Telnyx's OpenAI-compatible Responses API. This endpoint is compatible with the [OpenAI Responses API](https://developers.openai.com/api/reference/responses/overview) and may be used with the OpenAI JS or Python SDK by setting the base URL to `https://api.telnyx.com/v2/ai/openai`.

The `conversation` parameter refers to a Telnyx Conversation rather than an OpenAI-hosted conversation object. To persist a thread across turns, first [create a conversation](https://developers.telnyx.com/api-reference/conversations/create-a-conversation) with `POST /ai/conversations`, then pass that conversation's `id` in the Responses request as `conversation`. The endpoint appends the new input, assistant output, reasoning, and tool-call messages to that conversation. Reuse the same `conversation` id on subsequent Responses requests, including tool-result followups, so the model receives the prior context.

If `conversation` is omitted, the request is processed without persisting messages to a Telnyx conversation. Use the Conversations API to manage history: [list conversations](https://developers.telnyx.com/api-reference/conversations/list-conversations) (optionally filtered by metadata), [fetch messages](https://developers.telnyx.com/api-reference/conversations/get-conversation-messages) for a conversation, and optionally [add messages](https://developers.telnyx.com/api-reference/conversations/create-message) outside the Responses flow.

You can attach arbitrary metadata when creating a conversation (for example to tag the conversation's source, channel, or user) and later filter by it when listing conversations.

## Request body

- object
  - `conversation` string, uuid — Optional Telnyx Conversation ID from `POST /ai/conversations`. When provided, Telnyx stores this turn on that conversation and uses the conversation's prior messages as context. Reuse the same ID for subsequent turns and tool-result followups. Omit it for a non-persisted, stateless response.
  - `input` unknown
  - `instructions` string — Optional system/developer instructions for the model. When used with a persisted `conversation`, send these on the first request that creates the thread; subsequent turns can rely on the stored history.
  - `model` string — Model identifier to use for the response, for example `zai-org/GLM-5.1-FP8` or another model available from the Telnyx OpenAI-compatible models endpoint.
  - `service_tier` string — The service tier to use for this request. Supported values vary by model; use `GET /v2/ai/openai/models` and inspect the model's `service_tiers` field. If omitted, Telnyx-hosted models use `default`.
  - `stream` boolean — Set to `true` to stream Server-Sent Events, matching OpenAI's Responses streaming format.

## Response `200`

Successful Response

- object

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.net/team-telnyx/apis/telnyx-api-2.md) · [All operations](https://skmtc.net/team-telnyx/apis/telnyx-api-2/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/team-telnyx/telnyx-api-2/revisions/3fdc16374d70/schema)