# API Documentation
## Overview
The LangChain Documentation Server provides a comprehensive REST API for accessing LangChain documentation, API references, code examples, and tutorials in real-time.
## Base URL
- **Local Development**: `http://localhost:8000`
- **Docker**: `http://localhost:8080`
## Authentication
Currently, no authentication is required. Rate limiting may be implemented in the future.
## Endpoints
### Health Check
**GET** `/health`
Returns the current status of the service.
**Response:**
```json
{
"status": "ok",
"service": "LangChain Documentation Server",
"timestamp": "2025-07-04T10:34:12.123456",
"endpoints_available": 7,
"data_sources": [
"python.langchain.com",
"github.com/langchain-ai/langchain",
"pypi.org/project/langchain"
],
"features": [
"documentation_search",
"api_reference_lookup",
"github_examples",
"tutorials",
"version_info"
],
"architecture": "shared_service_layer"
}
```
### Search Documentation
**GET** `/search`
Search through LangChain documentation.
**Parameters:**
- `query` (required): Search term
- `max_results` (optional): Maximum results to return (1-50, default: 10)
**Example:**
```bash
curl "http://localhost:8000/search?query=llm&max_results=5"
```
### Search API Reference
**GET** `/search/api`
Search specifically through API reference documentation.
**Parameters:**
- `query` (required): Search term
- `max_results` (optional): Maximum results to return (1-50, default: 10)
### Get API Reference
**GET** `/api-reference/{class_name}`
Get detailed API reference for a specific class.
**Example:**
```bash
curl "http://localhost:8000/api-reference/ChatOpenAI"
```
### Get GitHub Examples
**GET** `/examples/github`
Get code examples from the LangChain GitHub repository.
**Parameters:**
- `topic` (required): Topic to search for
- `max_results` (optional): Maximum results to return (1-20, default: 5)
### Get Tutorials
**GET** `/tutorials`
Get LangChain tutorials and guides.
**Parameters:**
- `difficulty` (optional): Filter by difficulty level
- `max_results` (optional): Maximum results to return (1-30, default: 10)
### Get Latest Version
**GET** `/latest-version`
Get the latest LangChain version information from PyPI.
## Error Handling
The API returns standard HTTP status codes:
- `200 OK`: Successful request
- `400 Bad Request`: Invalid parameters
- `404 Not Found`: Resource not found
- `422 Unprocessable Entity`: Validation error
- `429 Too Many Requests`: Rate limit exceeded
- `500 Internal Server Error`: Server error
- `502 Bad Gateway`: External API error
Error responses include a detail message:
```json
{
"detail": "Error description"
}
```
## Rate Limiting
Currently no rate limiting is implemented, but it may be added in the future for production deployments.
## Interactive Documentation
Visit `/docs` when the server is running to access the interactive Swagger UI documentation.
