curl -X POST 'https://api.elevenlabs.io/v1/convai/knowledge-base?agent_id=' \
  -H "xi-api-key: $ELEVENLABS_API_KEY" \
  -F 'name=example-name' \
  -F 'url=https://example.com' \
  -F 'file=@sample.bin'

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

> Add To Knowledge Base

## 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/knowledge-base?agent_id=' \
  -H "xi-api-key: $ELEVENLABS_API_KEY" \
  -F 'name=example-name' \
  -F 'url=https://example.com'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| agent_id | query | string | No | query parameter agent_id. |
| name | body | string | No | A custom, human-readable name for the... |
| url | body | string | No | URL to a page of documentation that t... |
Other params: file

## Response (200 OK)
{"id":"string","name":"string","folder_path":[{"id":"string"}]}

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

POST

POST /v1/convai/knowledge-base — ElevenLabs API

ElevenLabs API

Add To Knowledge Base

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
→ 214 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/knowledge-base?agent_id=' \  -H "xi-api-key: $ELEVENLABS_API_KEY" \  -F 'name=example-name' \  -F 'url=https://example.com' \  -F '[email protected]'

Parameters

Name	In	Type	Required	Description
agent_id	query	string	No	query parameter agent_id.
name	body	string	No	A custom, human-readable name for the document.
url	body	string	No	URL to a page of documentation that the agent will have access to in order to interact with users.
file	body	string	No	Documentation that the agent will have access to in order to interact with users.

Response 200 OK

{
  "id": "string",
  "name": "string",
  "folder_path": [
    {
      "id": "string"
    }
  ]
}

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