Biel.ai API
Biel.ai is an AI-powered documentation assistant. It indexes your technical documentation and provides AI chat and search capabilities through widgets, MCP servers, and this REST API.
Base URL: https://app.biel.ai
The API is available on Business and Enterprise plans. Contact us to upgrade.
Chat, search, document retrieval, and answer continuations share your team's included interaction allowance. With extra usage enabled, interactions beyond that allowance cost $0.05 each.
Versioning
This document describes API v2 (/api/v2/). If you have an existing v1 integration, see the migration guide. v1 is scheduled for retirement in January 2027.
Authorization & permissions
Biel.ai uses API key authentication with granular permissions.
- Public projects: Widget operations, including reading project configuration, searching, and sending messages, do not require an API key. Project, source, conversation, sync, analytics, and team management operations require one; check each endpoint.
- Private projects: All operations require an API key.
Projects are public by default. Configure this in Project settings.
Available permissions
| Permission | Description | Required For |
|---|---|---|
projects_read | Read project details | Getting project information, listing projects |
projects_create | Create projects | Creating new projects |
projects_update | Update project settings | Updating project configuration |
projects_delete | Delete projects | Removing projects |
search | Search and read indexed documents within projects | Searching project content, retrieving indexed document text, tracking search clicks, submitting message feedback |
sources_read | View project sources | Listing project sources, getting source detail |
sources_create | Upload sources | Adding files, URLs, sitemaps, repositories, OpenAPI specs, and Confluence spaces to projects |
sources_delete | Delete sources | Removing sources from projects |
sync_create | Trigger a sync or a single-page re-crawl | Re-crawling project sources, re-crawling one page |
sync_read | Read sync status | Polling sync runs |
analytics_read | Read project analytics | Reading chat, search, MCP, and insights analytics |
chats_create | Create chats and send messages | Interacting with the AI chat |
chats_read | Read conversations | Listing chats, retrieving a conversation |
chats_delete | Delete conversations | Deleting a conversation |
teams_update | Update team settings | Renaming a team, changing its slug, managing members |
Keys created before v2 may carry legacy permission names (
project_read,project_search,project_sources_*,project_sync,chat_create). They remain valid as aliases of their v2 equivalents, so you don't need to re-issue keys.
Create an API key
- In app.biel.ai, click Team in the top navigation and scroll to API keys.
- Click Create API key and enter a Key name.
- Under Project access, select the intended project, or All projects in this team if the integration needs team-level operations. Select the required permissions.
- Click Create API Key and copy the key. You won't be able to view it again.
Using your API key
Include the key in the Authorization header:
Authorization: Api-Key <your-api-key>
Read-only keys (
projects_read,search) can be exposed client-side. Thesearchpermission allows retrieval that consumes interactions. Restrict client-side keys to the intended project and permissions. Keys with write permissions should always be stored server-side.
Authentication
- API Key: ApiKeyAuth
API Key authentication using the format: Api-Key <your-api-key>
Create your API key in Team Settings and assign the required permissions for your use case.
Security Scheme Type: | apiKey |
|---|---|
Header parameter name: | Authorization |