Advanced Features
API Reference
Integrate hej! directly into your applications.
The hej! API allows you to programmatically interact with your AI chatbot. Send messages, retrieve responses, and integrate chat functionality into your own applications.
Base URL
https://api.hej.chatAuthentication
API requests are authenticated using your domain. For public widget requests, the domain is passed via the data attribute. For server-to-server requests, contact us for API key access.
API Keys
API key authentication is available on Enterprise plans. Contact sales for access.
Endpoints
/api/chatOpen a WebSocket connection to send messages and receive streaming AI responses.
Connection
wss://api.hej.chat/api/chat?domain=your-domain.comSend Message
{
"message": "What are your business hours?",
"conversationId": "optional-conversation-id"
}Response Events
The server sends streaming events over the WebSocket connection:
| Event | Description |
|---|---|
text | Streaming text chunk from the AI |
tool-call | AI is invoking a tool (e.g. search, custom tool) |
done | Response complete |
/api/site-public/:domainRetrieve widget configuration for a domain.
Response
{
"headerBgColor": "#ffffff",
"headerTextColor": "#000000",
"title": "Chat with us",
"subtitle": "We're here to help",
"position": "right"
}/api/documentRetrieve the content of a specific indexed page.
Request Body
{
"domain": "your-domain.com",
"url": "https://your-domain.com/about"
}Rate Limits
API requests are rate-limited based on your plan:
| Plan | Requests/minute | Conversations/month |
|---|---|---|
| Starter | 60 | 5,000 |
| Growth | 120 | 10,000 |
| Business | 300 | 50,000 |
| Enterprise | Custom | Unlimited |
Error Handling
{
"error": {
"code": "RATE_LIMIT_EXCEEDED",
"message": "Too many requests. Please try again later.",
"retryAfter": 60
}
}| Code | Description |
|---|---|
DOMAIN_NOT_FOUND | Domain is not registered |
RATE_LIMIT_EXCEEDED | Too many requests |
QUOTA_EXCEEDED | Monthly conversation limit reached |
SUBSCRIPTION_INACTIVE | Subscription is inactive |