# API Reference

Hold Slayer exposes a REST API, WebSocket endpoint, and MCP server.

## REST API

Base URL: `http://localhost:8000/api`

### Calls

#### Place an Outbound Call

```
POST /api/calls/outbound
```

**Request:**

```json
{
  "number": "+18005551234",
  "mode": "hold_slayer",
  "intent": "dispute Amazon charge from December 15th",
  "device": "sip_phone",
  "call_flow_id": "chase_bank_disputes",
  "services": {
    "recording": true,
    "transcription": true
  }
}
```

**Call Modes:**

| Mode | Description |
|------|-------------|
| `direct` | Dial and connect to your device immediately |
| `hold_slayer` | Navigate IVR, wait on hold, transfer when human detected |
| `ai_assisted` | Connect with noise cancel, transcription, recording |

**Response:**

```json
{
  "call_id": "call_abc123",
  "status": "trying",
  "number": "+18005551234",
  "mode": "hold_slayer",
  "started_at": "2026-01-15T10:30:00Z"
}
```

#### Launch Hold Slayer

```
POST /api/calls/hold-slayer
```

Convenience endpoint — equivalent to `POST /outbound` with `mode=hold_slayer`.

**Request:**

```json
{
  "number": "+18005551234",
  "intent": "dispute Amazon charge from December 15th",
  "call_flow_id": "chase_bank_disputes",
  "transfer_to": "sip_phone"
}
```

#### Get Call Status

```
GET /api/calls/{call_id}
```

**Response:**

```json
{
  "call_id": "call_abc123",
  "status": "on_hold",
  "number": "+18005551234",
  "mode": "hold_slayer",
  "duration": 847,
  "hold_time": 780,
  "audio_type": "music",
  "transcript_excerpt": "...your call is important to us...",
  "classification_history": [
    {"timestamp": 1706000000, "type": "ringing", "confidence": 0.95},
    {"timestamp": 1706000003, "type": "ivr_prompt", "confidence": 0.88},
    {"timestamp": 1706000010, "type": "music", "confidence": 0.92}
  ],
  "services": {"recording": true, "transcription": true}
}
```

#### List Active Calls

```
GET /api/calls
```

**Response:**

```json
{
  "calls": [
    {"call_id": "call_abc123", "status": "on_hold", "number": "+18005551234", "duration": 847},
    {"call_id": "call_def456", "status": "connected", "number": "+18009876543", "duration": 120}
  ],
  "total": 2
}
```

#### End a Call

```
POST /api/calls/{call_id}/hangup
```

#### Transfer a Call

```
POST /api/calls/{call_id}/transfer
```

**Request:**

```json
{
  "device": "sip_phone"
}
```

### Call Flows

#### List Call Flows

```
GET /api/call-flows
GET /api/call-flows?company=Chase+Bank
GET /api/call-flows?tag=banking
```

**Response:**

```json
{
  "flows": [
    {
      "id": "chase_bank_disputes",
      "name": "Chase Bank — Disputes",
      "company": "Chase Bank",
      "phone_number": "+18005551234",
      "step_count": 7,
      "success_count": 12,
      "fail_count": 1,
      "tags": ["banking", "disputes"]
    }
  ]
}
```

#### Get Call Flow

```
GET /api/call-flows/{flow_id}
```

Returns the full call flow with all steps.

#### Create Call Flow

```
POST /api/call-flows
```

**Request:**

```json
{
  "name": "Chase Bank — Disputes",
  "company": "Chase Bank",
  "phone_number": "+18005551234",
  "steps": [
    {"id": "wait", "type": "WAIT", "description": "Wait for greeting", "timeout": 5.0, "next_step": "menu"},
    {"id": "menu", "type": "LISTEN", "description": "Main menu", "next_step": "press3"},
    {"id": "press3", "type": "DTMF", "description": "Account services", "dtmf": "3", "next_step": "hold"},
    {"id": "hold", "type": "HOLD", "description": "Wait for agent", "next_step": "transfer"},
    {"id": "transfer", "type": "TRANSFER", "description": "Connect to user"}
  ]
}
```

#### Update Call Flow

```
PUT /api/call-flows/{flow_id}
```

#### Delete Call Flow

```
DELETE /api/call-flows/{flow_id}
```

### Devices

#### List Registered Devices

```
GET /api/devices
```

**Response:**

```json
{
  "devices": [
    {
      "id": "dev_001",
      "name": "Office SIP Phone",
      "type": "sip_phone",
      "sip_uri": "sip:robert@gateway.helu.ca",
      "is_online": true,
      "priority": 10
    }
  ]
}
```

#### Register a Device

```
POST /api/devices
```

**Request:**

```json
{
  "name": "Office SIP Phone",
  "type": "sip_phone",
  "sip_uri": "sip:robert@gateway.helu.ca",
  "priority": 10,
  "capabilities": ["voice"]
}
```

#### Update Device

```
PUT /api/devices/{device_id}
```

#### Remove Device

```
DELETE /api/devices/{device_id}
```

### Error Responses

All errors follow a consistent format:

```json
{
  "detail": "Call not found: call_xyz789"
}
```

| Status Code | Meaning |
|-------------|---------|
| `400` | Bad request (invalid parameters) |
| `404` | Resource not found (call, flow, device) |
| `409` | Conflict (call already ended, device already registered) |
| `500` | Internal server error |

## WebSocket

### Event Stream

```
ws://localhost:8000/ws/events
ws://localhost:8000/ws/events?call_id=call_abc123
ws://localhost:8000/ws/events?types=human_detected,hold_detected
```

**Query Parameters:**

| Param | Description |
|-------|-------------|
| `call_id` | Filter events for a specific call |
| `types` | Comma-separated event types to receive |

**Event Format:**

```json
{
  "type": "hold_detected",
  "call_id": "call_abc123",
  "timestamp": "2026-01-15T10:35:00Z",
  "data": {
    "audio_type": "music",
    "confidence": 0.92,
    "hold_duration": 0
  }
}
```

### Event Types

| Type | Data Fields |
|------|------------|
| `call_started` | `number`, `mode`, `intent` |
| `call_ringing` | `number` |
| `call_connected` | `number`, `duration` |
| `call_ended` | `number`, `duration`, `reason` |
| `call_failed` | `number`, `error` |
| `hold_detected` | `audio_type`, `confidence` |
| `human_detected` | `confidence`, `transcript_excerpt` |
| `transfer_started` | `device`, `from_call_id` |
| `transfer_complete` | `device`, `bridge_id` |
| `ivr_step` | `step_id`, `step_type`, `description` |
| `ivr_dtmf_sent` | `digits`, `step_id` |
| `ivr_menu_detected` | `transcript`, `options` |
| `audio_classified` | `audio_type`, `confidence`, `features` |
| `transcript_chunk` | `text`, `speaker`, `is_final` |
| `recording_started` | `recording_id`, `path` |
| `recording_stopped` | `recording_id`, `duration`, `file_size` |

### Client Example

```javascript
const ws = new WebSocket("ws://localhost:8000/ws/events");

ws.onopen = () => {
  console.log("Connected to Hold Slayer events");
};

ws.onmessage = (event) => {
  const data = JSON.parse(event.data);
  
  switch (data.type) {
    case "human_detected":
      alert("🚨 A live person picked up! Pick up your phone!");
      break;
    case "hold_detected":
      console.log("⏳ On hold...");
      break;
    case "transcript_chunk":
      console.log(`📝 ${data.data.speaker}: ${data.data.text}`);
      break;
  }
};

ws.onerror = (error) => {
  console.error("WebSocket error:", error);
};
```

### Python Client Example

```python
import asyncio
import websockets
import json

async def listen():
    async with websockets.connect("ws://localhost:8000/ws/events") as ws:
        async for message in ws:
            event = json.loads(message)
            print(f"[{event['type']}] {event.get('data', {})}")

asyncio.run(listen())
```