curl -X POST 'https://api.elevenlabs.io/v1/convai/realtime/client_secrets' \
  -H "xi-api-key: $ELEVENLABS_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "session": {
    "type": "realtime",
    "model": "eleven_realtime_v1_mini",
    "instructions": "",
    "output_modalities": [
      "example-output-modalities"
    ],
    "audio": {
      "input": {
        "format": {
          "type": "audio/pcm",
          "rate": 24000
        },
        "transcription": {
          "language": "example-language"
        },
        "turn_detection": {
          "type": "semantic_vad",
          "eagerness": "medium",
          "create_response": true,
          "interrupt_response": true,
          "threshold": 0,
          "prefix_padding_ms": 0,
          "silence_duration_ms": 0,
          "turn_timeout": -1
        },
        "pacing": "realtime"
      },
      "output": {
        "format": {
          "type": "audio/pcm"
        },
        "voice": "brian"
      }
    },
    "tools": [
      {
        "type": "function",
        "name": "example-name",
        "description": "",
        "parameters": {}
      }
    ],
    "tool_choice": "auto",
    "temperature": 0.7,
    "max_response_output_tokens": 4096,
    "max_duration_seconds": 600,
    "turn_detection": "__unset__",
    "tracing": "example-tracing",
    "include": [
      "example-include"
    ],
    "parallel_tool_calls": true,
    "reasoning": {},
    "truncation": "example-truncation",
    "prompt": {}
  },
  "expires_after": {
    "anchor": "created_at",
    "seconds": 0
  }
}'

# POST /v1/convai/realtime/client_secrets (ElevenLabs API)
Base URL: https://api.elevenlabs.io
Auth: xi-api-key: <ELEVENLABS_API_KEY>
Last verified: 2026-10-20

> Create Realtime Client Secret

## Critical Gotchas
* Authentication uses the non-standard `xi-api-key` header, not `Authorization: Bearer`. Sending a Bearer token returns HTTP 401.
* Text-to-speech responses are raw binary audio, not JSON. Write the body to a file (`--output speech.mp3`) rather than parsing it.

## cURL
curl -X POST 'https://api.elevenlabs.io/v1/convai/realtime/client_secrets' \
  -H "xi-api-key: $ELEVENLABS_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{"session":{"type":"realtime","model":"eleven_realtime_v1_mini"},"expires_after":{"anchor":"created_at","seconds":0}}'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| session | body | object | No | Request body field session. |
| expires_after | body | object | No | Request body field expires_after. |

## Response (200 OK)
{"value":"string","expires_at":0}

---
Need an API key? Get one at https://elevenlabs.io/app/sign-up

POST

POST /v1/convai/realtime/client_secrets — ElevenLabs API

ElevenLabs API

Create Realtime Client Secret

Base URL: https://api.elevenlabs.io
Auth: xi-api-key: <ELEVENLABS_API_KEY>
Last verified: 2026-10-20 · upstream hash matched

Actions Try in browser→

Agents: curl -H "Accept: text/markdown" this URL
→ 186 tokens · Vary: Accept

Critical gotchas

Authentication uses the non-standard xi-api-key header, not Authorization: Bearer. Sending a Bearer token returns HTTP 401.

Text-to-speech responses are raw binary audio, not JSON. Write the body to a file (--output speech.mp3) rather than parsing it.

cURL

curl -X POST 'https://api.elevenlabs.io/v1/convai/realtime/client_secrets' \  -H "xi-api-key: $ELEVENLABS_API_KEY" \  -H 'Content-Type: application/json' \  -d '{  "session": {    "type": "realtime",    "model": "eleven_realtime_v1_mini",    "instructions": "",    "output_modalities": [      "example-output-modalities"    ],    "audio": {      "input": {        "format": {          "type": "audio/pcm",          "rate": 24000        },        "transcription": {          "language": "example-language"        },        "turn_detection": {          "type": "semantic_vad",          "eagerness": "medium",          "create_response": true,          "interrupt_response": true,          "threshold": 0,          "prefix_padding_ms": 0,          "silence_duration_ms": 0,          "turn_timeout": -1        },        "pacing": "realtime"      },      "output": {        "format": {          "type": "audio/pcm"        },        "voice": "brian"      }    },    "tools": [      {        "type": "function",        "name": "example-name",        "description": "",        "parameters": {}      }    ],    "tool_choice": "auto",    "temperature": 0.7,    "max_response_output_tokens": 4096,    "max_duration_seconds": 600,    "turn_detection": "__unset__",    "tracing": "example-tracing",    "include": [      "example-include"    ],    "parallel_tool_calls": true,    "reasoning": {},    "truncation": "example-truncation",    "prompt": {}  },  "expires_after": {    "anchor": "created_at",    "seconds": 0  }}'

Parameters

Name	In	Type	Required	Description
session	body	object	No	Request body field session.
expires_after	body	object	No	Request body field expires_after.

Response 200 OK

{
  "value": "string",
  "expires_at": 0,
  "session": {
    "type": "realtime",
    "model": "eleven_realtime_v1_mini",
    "instructions": "",
    "output_modalities": [
      "string"
    ],
    "audio": {
      "input": {
        "format": {
          "type": "audio/pcm",
          "rate": 24000
        },
        "transcription": {
          "language": "string"
        },
        "turn_detection": {
          "type": "semantic_vad",
          "eagerness": "medium",
          "create_response": true,
          "interrupt_response": true,
          "threshold": 0,
          "prefix_padding_ms": 0,
          "silence_duration_ms": 0,
          "turn_timeout": -1
        },
        "pacing": "realtime"
      },
      "output": {
        "format": {
          "type": "audio/pcm"
        },
        "voice": "brian"
      }
    },
    "tools": [
      {
        "type": "function",
        "name": "string",
        "description": "",
        "parameters": {}
      }
    ],
    "tool_choice": "auto",
    "temperature": 0.7,
    "max_response_output_tokens": 4096,
    "max_duration_seconds": 600,
    "tracing": "string"
  }
}

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