Documentation
Everything you need to know about creating and using hotlines.
Overview
A hotline is an always-on conversational endpoint. It operates on a phone number, handling voice calls and SMS messages. Hotlines capture data, connect people, and take action—all through natural conversation.
Hotlines are not bots or IVRs. They're services that happen to be accessed by phone.
Channels
Hotlines support multiple channels for interaction:
| Channel | Status | Description |
|---|---|---|
| Voice | Available | Primary channel. Call and converse naturally. |
| SMS | Available | Text-based interaction with slash commands. |
| Coming | Email-based conversations. | |
| API/MCP | Available | Programmatic access for agents and integrations. |
Voice
Voice is the primary channel. Just call and talk naturally.
Keypad Actions
During a call, you can use the keypad for quick actions:
| Key | Action | Description |
|---|---|---|
* | Mute/Unmute | Toggle your microphone |
# | Number Entry | Enter a number (e.g., account ID) |
0 | Operator | Request transfer to a human |
1-9 | Shortcuts | Hotline-specific quick actions |
Tips
- Speak naturally—no special commands needed
- The hotline will ask clarifying questions if needed
- Say "text me" to receive information via SMS
- Say "transfer me" to connect with a human (if available)
SMS
Text the hotline number for text-based interaction.
Slash Commands
SMS supports special commands prefixed with /:
| Command | Description |
|---|---|
/help | Show available commands |
/card | Get a contact card for the hotline |
/call | Request a callback |
/stop | Unsubscribe from messages |
Regular Messages
Just text naturally. The hotline understands context and remembers your conversation history.
API & MCP
Developers and AI agents can interact with hotlines programmatically.
REST API
Every hotline has an API endpoint for programmatic access:
POST https://api.hotline.dev/v1/hotlines/{id}/message
Content-Type: application/json
Authorization: Bearer {token}
{
"message": "Your message here",
"caller_id": "optional-caller-identifier"
}MCP Server
Hotlines expose an MCP (Model Context Protocol) server for AI agent integration. This enables agent-to-agent communication through hotlines.
{
"mcpServers": {
"hotline": {
"url": "https://mcp.hotline.dev/v1/hotlines/{id}"
}
}
}Primitives
Hotlines are built from composable primitives:
Capture
Collect structured information during conversation. The hotline extracts and stores relevant data automatically—names, numbers, preferences, requests.
Memory
Recognize returning callers and maintain context across conversations. The hotline remembers who you are and what you've discussed.
Knowledge
Search across uploaded documents and past conversations. The hotline can answer questions based on its knowledge base.
Actions
The hotline can take action:
- Send SMS — Text confirmations, links, follow-ups
- Transfer calls — Connect to humans or other hotlines
- Trigger webhooks — Notify external systems
Integrations
Connect to external systems: calendars, CRMs, databases, APIs. The hotline can schedule appointments, create records, look up information.
Creating a Hotline
Two ways to create a hotline:
Online
Create at create.hotline.free — Configure everything through the web interface.
By Voice
Call the Concierge at (808) 468-5544. Describe what you want and the Concierge will create it for you.
Managing Your Hotline
After creating a hotline, you can:
- View call history and transcripts
- Upload knowledge documents
- Configure integrations
- Set up transfer numbers
- Customize the voice and personality
- View analytics and insights
All management happens at create.hotline.free.