---
title: REST API
description: docs-builder includes a REST API server (Elastic.Documentation.Api) that powers search, AI assistance, and content change feeds for the documentation...
url: https://docs-v3-preview.elastic.dev/elastic/docs-builder/pull/4843/data/api
products:
  - Elastic Docs Builder
---

# REST API
docs-builder includes a REST API server (`Elastic.Documentation.Api`) that powers search, AI assistance, and content change feeds for the documentation site.

## Endpoints


| Endpoint          | Description                                                             |
|-------------------|-------------------------------------------------------------------------|
| Search            | Full-text and semantic search across all published documentation        |
| Navigation search | Search scoped to navigation structure and page titles                   |
| Ask AI            | Streaming endpoint for AI-powered question answering over documentation |
| Changes feed      | Content change feed for tracking documentation updates                  |


## Ask AI provider

Each deployment of the API server picks its Ask AI provider with the `DOCUMENTATION_ASK_AI_PROVIDER` setting. A request can't change it.

| Value          | Provider                  |
|----------------|---------------------------|
| Unset or empty | LLM Gateway (the default) |
| `LlmGateway`   | LLM Gateway               |
| `AgentBuilder` | Agent Builder             |

The value is case-insensitive. Any other value stops the Ask AI service with a configuration error. LLM Gateway needs `LLM_GATEWAY_FUNCTION_URL` and `LLM_GATEWAY_SERVICE_ACCOUNT`. Agent Builder needs `DOCUMENTATION_KIBANA_URL` and `DOCUMENTATION_KIBANA_APIKEY`. A deployment that uses Agent Builder, such as Codex, must set `DOCUMENTATION_ASK_AI_PROVIDER=AgentBuilder`.
<note>
  A formal OpenAPI specification should be generated from the API server as a follow-up. This page will be updated with full endpoint details, request/response schemas, and authentication requirements once the spec is available.
</note>