curl -X POST 'https://api.elevenlabs.io/v1/studio/projects/project-id/chapters/chapter-id' \
  -H "xi-api-key: $ELEVENLABS_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "name": "string",
  "content": {
    "blocks": [
      {
        "sub_type": "p",
        "nodes": [
          {
            "type": "[recursive or deeply nested schema]",
            "text": "[recursive or deeply nested schema]",
            "voice_id": "[recursive or deeply nested schema]"
          }
        ],
        "block_id": "string"
      }
    ]
  }
}'

# POST /v1/studio/projects/{project_id}/chapters/{chapter_id} (ElevenLabs API)
Base URL: https://api.elevenlabs.io
Auth: xi-api-key: <ELEVENLABS_API_KEY>
Last verified: 2026-09-03

> Update Chapter

## 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/studio/projects/project-id/chapters/chapter-id' \
  -H "xi-api-key: $ELEVENLABS_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{"name":"string","content":{"blocks":[]}}'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| project_id | path | string | Yes | The ID of the Studio project. |
| chapter_id | path | string | Yes | The ID of the chapter. |
| name | body | string | No | The name of the chapter, used for identification only. |
| content | body | object | No | The chapter content to use. |

## Response (200 OK)
{"chapter":{"can_be_downloaded":true,"chapter_id":"aw1NgEzBg83R7vgmiJt6"}}

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

POST

/v1/studio/projects/{project_id}/chapters/{chapter_id}

ElevenLabs API

Update Chapter

Base URL: https://api.elevenlabs.io
Auth: xi-api-key: <ELEVENLABS_API_KEY>
Last verified: 2026-09-03 · upstream hash matched

Actions

Agents: curl -H "Accept: text/markdown" this URL
→ 232 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/studio/projects/project-id/chapters/chapter-id' \  -H "xi-api-key: $ELEVENLABS_API_KEY" \  -H 'Content-Type: application/json' \  -d '{  "name": "string",  "content": {    "blocks": [      {        "sub_type": "p",        "nodes": [          {            "type": "[recursive or deeply nested schema]",            "text": "[recursive or deeply nested schema]",            "voice_id": "[recursive or deeply nested schema]"          }        ],        "block_id": "string"      }    ]  }}'

Get a free ElevenLabs API key → sponsored

Parameters

Name	In	Type	Required	Description
project_id	path	string	Yes	The ID of the Studio project.
chapter_id	path	string	Yes	The ID of the chapter.
name	body	string	No	The name of the chapter, used for identification only.
content	body	object	No	The chapter content to use.

Response 200 OK

{
  "chapter": {
    "can_be_downloaded": true,
    "chapter_id": "aw1NgEzBg83R7vgmiJt6",
    "content": {
      "blocks": []
    },
    "conversion_progress": 0.5,
    "last_conversion_date_unix": 1714204800,
    "name": "Chapter 1",
    "state": "default",
    "statistics": {
      "characters_converted": 200,
      "characters_unconverted": 100,
      "paragraphs_converted": 5,
      "paragraphs_unconverted": 3
    }
  }
}