curl -X POST 'https://api.openai.com/v1/realtime/calls/call-id/refer' \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "target_uri": "tel:+14155550123"
}'

# POST /realtime/calls/{call_id}/refer (OpenAI API)
Base URL: https://api.openai.com/v1
Auth: Authorization; OpenAI API key; required.
Request formats: application/json.
Last verified: 2026-10-20

> Refer call

## Critical Gotchas
* The Responses API is the primary interface for new text and tool workflows; Chat Completions remains a separate compatibility API.
* Audio transcription uploads use multipart form data rather than a JSON request body.

## cURL
curl -X POST 'https://api.openai.com/v1/realtime/calls/call-id/refer' \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "target_uri": "tel:+14155550123"
}'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| call_id | path | string | Yes | The identifier for the call provided in the [`realtime.call.incoming`](https:... |
| target_uri | body | string | Yes | URI that should appear in the SIP Refer-To header. Supports values like `tel:... |

## Response example
null

---
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POST

POST /realtime/calls/{call_id}/refer — OpenAI API

OpenAI API key (required); https://api.openai.com/v1

OpenAI API

Refer call

Base URL: https://api.openai.com/v1
Auth: Authorization: Bearer <OPENAI_API_KEY>
Last verified: 2026-10-20 · upstream hash matched

Actions Try in browser→

Agents: curl -H "Accept: text/markdown" this URL
→ 210 tokens · Vary: Accept

Critical gotchas

The Responses API is the primary interface for new text and tool workflows; Chat Completions remains a separate compatibility API.

Audio transcription uploads use multipart form data rather than a JSON request body.

cURL

curl -X POST 'https://api.openai.com/v1/realtime/calls/call-id/refer' \  -H "Authorization: Bearer $OPENAI_API_KEY" \  -H 'Content-Type: application/json' \  -d '{  "target_uri": "tel:+14155550123"}'

Parameters

Name	In	Type	Required	Description
call_id	path	string	Yes	The identifier for the call provided in the [`realtime.call.incoming`](https://developers.openai.com/api/reference/resources/webhooks#realtime.call.incoming) webhook.
target_uri	body	string	Yes	URI that should appear in the SIP Refer-To header. Supports values like `tel:+14155550123` or `sip:[email protected]`.

Response 200 OK

null

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