Account
└── Agent (AI persona — owns numbers, handles calls/SMS)
    ├── Phone Number (attached to agent)
    │   ├── Call (inbound/outbound voice)
    │   │   └── Transcript (call recording text)
    │   └── Message (SMS)
    │       └── Conversation (threaded SMS exchange)
    └── Webhook (per-agent event delivery)
Webhook (project-level event delivery)

curl -X POST https://api.agentphone.to/v1/agents \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Support Bot",
    "description": "Handles customer support calls",
    "voiceMode": "hosted",
    "systemPrompt": "You are a friendly customer support agent. Help the caller with their questions.",
    "beginMessage": "Hi there! How can I help you today?"
  }'

{
  "id": "agent_abc123",
  "name": "Support Bot",
  "description": "Handles customer support calls",
  "voiceMode": "hosted",
  "systemPrompt": "You are a friendly customer support agent...",
  "beginMessage": "Hi there! How can I help you today?",
  "voice": "11labs-Brian",
  "phoneNumbers": [],
  "createdAt": "2025-01-15T10:30:00.000Z"
}

curl -X POST https://api.agentphone.to/v1/numbers \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "country": "US",
    "areaCode": "415",
    "agentId": "agent_abc123"
  }'

{
  "id": "pn_xyz789",
  "phoneNumber": "+14155551234",
  "country": "US",
  "status": "active",
  "agentId": "agent_abc123",
  "createdAt": "2025-01-15T10:31:00.000Z"
}

curl -X POST https://api.agentphone.to/v1/calls \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "agentId": "agent_abc123",
    "toNumber": "+14155559999",
    "systemPrompt": "Schedule a dentist appointment for next Tuesday at 2pm.",
    "initialGreeting": "Hi, I am calling to schedule an appointment."
  }'

{
  "id": "call_def456",
  "agentId": "agent_abc123",
  "fromNumber": "+14155551234",
  "toNumber": "+14155559999",
  "direction": "outbound",
  "status": "in-progress",
  "startedAt": "2025-01-15T10:32:00.000Z"
}

curl https://api.agentphone.to/v1/calls/call_def456/transcript \
  -H "Authorization: Bearer YOUR_API_KEY"

{
  "data": [
    {
      "id": "tx_001",
      "transcript": "Hi, I am calling to schedule an appointment.",
      "response": null,
      "confidence": 0.95,
      "createdAt": "2025-01-15T10:32:01.000Z"
    },
    {
      "id": "tx_002",
      "transcript": "Sure, what day works for you?",
      "response": "Next Tuesday at 2pm would be great.",
      "confidence": 0.92,
      "createdAt": "2025-01-15T10:32:05.000Z"
    }
  ]
}

Authorization: Bearer YOUR_API_KEY

curl https://api.agentphone.to/v1/usage \
  -H "Authorization: Bearer YOUR_API_KEY"

{
  "plan": { "name": "free", "numberLimit": 1 },
  "numbers": { "used": 1, "limit": 1 },
  "stats": {
    "messagesLast30d": 42,
    "callsLast30d": 15,
    "minutesLast30d": 67
  }
}

curl -X POST https://api.agentphone.to/v1/agents \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Sales Agent",
    "description": "Handles outbound sales calls",
    "voiceMode": "hosted",
    "systemPrompt": "You are a professional sales agent. Be persuasive but not pushy.",
    "beginMessage": "Hi! Thanks for taking my call.",
    "voice": "alloy"
  }'

{
  "id": "agent_abc123",
  "name": "Sales Agent",
  "description": "Handles outbound sales calls",
  "voiceMode": "hosted",
  "systemPrompt": "You are a professional sales agent...",
  "beginMessage": "Hi! Thanks for taking my call.",
  "voice": "alloy",
  "phoneNumbers": [],
  "createdAt": "2025-01-15T10:30:00.000Z"
}

curl "https://api.agentphone.to/v1/agents?limit=20" \
  -H "Authorization: Bearer YOUR_API_KEY"

curl https://api.agentphone.to/v1/agents/AGENT_ID \
  -H "Authorization: Bearer YOUR_API_KEY"

curl -X PATCH https://api.agentphone.to/v1/agents/AGENT_ID \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Updated Bot",
    "systemPrompt": "You are a customer support specialist. Be empathetic and helpful.",
    "voice": "nova"
  }'

curl -X DELETE https://api.agentphone.to/v1/agents/AGENT_ID \
  -H "Authorization: Bearer YOUR_API_KEY"

{
  "success": true,
  "message": "Agent deleted",
  "unassignedNumbers": ["pn_xyz789"]
}

curl -X POST https://api.agentphone.to/v1/agents/AGENT_ID/numbers \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"numberId": "pn_xyz789"}'

curl -X DELETE https://api.agentphone.to/v1/agents/AGENT_ID/numbers/NUMBER_ID \
  -H "Authorization: Bearer YOUR_API_KEY"

curl "https://api.agentphone.to/v1/agents/AGENT_ID/conversations?limit=20" \
  -H "Authorization: Bearer YOUR_API_KEY"

curl "https://api.agentphone.to/v1/agents/AGENT_ID/calls?limit=20" \
  -H "Authorization: Bearer YOUR_API_KEY"

curl https://api.agentphone.to/v1/agents/voices \
  -H "Authorization: Bearer YOUR_API_KEY"

{
  "data": [
    { "voiceId": "11labs-Brian", "name": "Brian", "provider": "elevenlabs", "gender": "male" },
    { "voiceId": "alloy", "name": "Alloy", "provider": "openai", "gender": "neutral" },
    { "voiceId": "nova", "name": "Nova", "provider": "openai", "gender": "female" }
  ]
}

curl -X POST https://api.agentphone.to/v1/numbers \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "country": "US",
    "areaCode": "415",
    "agentId": "agent_abc123"
  }'

{
  "id": "pn_xyz789",
  "phoneNumber": "+14155551234",
  "country": "US",
  "status": "active",
  "agentId": "agent_abc123",
  "createdAt": "2025-01-15T10:31:00.000Z"
}

curl "https://api.agentphone.to/v1/numbers?limit=20" \
  -H "Authorization: Bearer YOUR_API_KEY"

{
  "data": [
    {
      "id": "pn_xyz789",
      "phoneNumber": "+14155551234",
      "country": "US",
      "status": "active",
      "agentId": "agent_abc123"
    }
  ],
  "total": 1
}

curl -X DELETE https://api.agentphone.to/v1/numbers/NUMBER_ID \
  -H "Authorization: Bearer YOUR_API_KEY"

{"text": "Let me check that for you.", "interim": true}
{"text": "Your order #4521 shipped yesterday via FedEx."}

{ "text": "How can I help you?" }

from fastapi.responses import StreamingResponse
import json, openai

@app.post('/webhook')
async def handle_voice(payload: dict):
    if payload['channel'] != 'voice':
        return Response(status_code=200)

    history = payload.get('recentHistory', [])
    context = "\n".join([
        f"{'Customer' if h['direction'] == 'inbound' else 'Agent'}: {h['content']}"
        for h in history
    ])

    async def generate():
        yield json.dumps({"text": "One moment, let me check.", "interim": True}) + "\n"

        stream = openai.chat.completions.create(
            model="gpt-4",
            stream=True,
            messages=[
                {"role": "system", "content": "You are a helpful phone agent."},
                {"role": "user", "content": f"Conversation:\n{context}\n\nRespond."}
            ]
        )
        full = ""
        for chunk in stream:
            delta = chunk.choices[0].delta.content or ""
            full += delta
        yield json.dumps({"text": full}) + "\n"

    return StreamingResponse(generate(), media_type="application/x-ndjson")

const OpenAI = require('openai');
const openai = new OpenAI();

app.post('/webhook', express.json(), async (req, res) => {
  if (req.body.channel !== 'voice') return res.status(200).send('OK');

  const history = req.body.recentHistory || [];
  const context = history
    .map(h => `${h.direction === 'inbound' ? 'Customer' : 'Agent'}: ${h.content}`)
    .join('\n');

  res.setHeader('Content-Type', 'application/x-ndjson');
  res.write(JSON.stringify({ text: 'One moment, let me check.', interim: true }) + '\n');

  const stream = await openai.chat.completions.create({
    model: 'gpt-4',
    stream: true,
    messages: [
      { role: 'system', content: 'You are a helpful phone agent.' },
      { role: 'user', content: `Conversation:\n${context}\n\nRespond.` }
    ]
  });

  let full = '';
  for await (const chunk of stream) {
    full += chunk.choices[0]?.delta?.content || '';
  }
  res.write(JSON.stringify({ text: full }) + '\n');
  res.end();
});

from flask import Flask, request, Response
import json, anthropic, os

app = Flask(__name__)
client = anthropic.Anthropic(api_key=os.environ["ANTHROPIC_API_KEY"])

TOOLS = [
    {
        "name": "get_todays_calendar",
        "description": "Get the user's calendar events for today.",
        "input_schema": {"type": "object", "properties": {}, "required": []},
    },
    {
        "name": "search_orders",
        "description": "Look up a customer's recent orders.",
        "input_schema": {
            "type": "object",
            "properties": {"query": {"type": "string"}},
            "required": ["query"],
        },
    },
]

TOOL_HANDLERS = {
    "get_todays_calendar": lambda args: fetch_calendar_events(),
    "search_orders": lambda args: search_order_db(args["query"]),
}


def run_tool_call(user_message: str, history: list) -> str:
    """Run Claude with tools and return the final text response."""
    messages = [{"role": "user", "content": user_message}]

    for _ in range(5):  # max tool-call iterations
        response = client.messages.create(
            model="claude-haiku-4-5-20251001",
            max_tokens=256,
            system="You are a helpful phone assistant. Keep responses to 2-3 sentences.",
            tools=TOOLS,
            messages=messages,
        )

        if response.stop_reason == "tool_use":
            messages.append({"role": "assistant", "content": response.content})
            tool_results = []
            for block in response.content:
                if block.type == "tool_use":
                    handler = TOOL_HANDLERS.get(block.name)
                    result = handler(block.input) if handler else "Unknown tool"
                    tool_results.append({
                        "type": "tool_result",
                        "tool_use_id": block.id,
                        "content": result,
                    })
            messages.append({"role": "user", "content": tool_results})
        else:
            return " ".join(b.text for b in response.content if hasattr(b, "text"))

    return "Sorry, I'm having trouble processing that."


@app.post("/webhook")
def webhook():
    payload = request.json
    if payload.get("channel") != "voice":
        return "OK", 200

    transcript = payload["data"].get("transcript", "")
    history = payload.get("recentHistory", [])

    def generate():
        # Immediately tell the caller we're working on it
        yield json.dumps({"text": "Let me check on that.", "interim": True}) + "\n"

        # Now run the slow tool calls (LLM + external APIs)
        try:
            answer = run_tool_call(transcript, history)
        except Exception:
            answer = "Sorry, I ran into a problem. Could you try again?"

        yield json.dumps({"text": answer}) + "\n"

    return Response(generate(), content_type="application/x-ndjson")

const express = require("express");
const Anthropic = require("@anthropic-ai/sdk");

const app = express();
app.use(express.json());

const client = new Anthropic();

const tools = [
  {
    name: "get_todays_calendar",
    description: "Get the user's calendar events for today.",
    input_schema: { type: "object", properties: {}, required: [] },
  },
  {
    name: "search_orders",
    description: "Look up a customer's recent orders.",
    input_schema: {
      type: "object",
      properties: { query: { type: "string" } },
      required: ["query"],
    },
  },
];

const toolHandlers = {
  get_todays_calendar: (args) => fetchCalendarEvents(),
  search_orders: (args) => searchOrderDb(args.query),
};

async function runToolCall(userMessage) {
  const messages = [{ role: "user", content: userMessage }];

  for (let i = 0; i < 5; i++) {
    const response = await client.messages.create({
      model: "claude-haiku-4-5-20251001",
      max_tokens: 256,
      system: "You are a helpful phone assistant. Keep responses to 2-3 sentences.",
      tools,
      messages,
    });

    if (response.stop_reason === "tool_use") {
      messages.push({ role: "assistant", content: response.content });
      const toolResults = [];
      for (const block of response.content) {
        if (block.type === "tool_use") {
          const handler = toolHandlers[block.name];
          const result = handler ? await handler(block.input) : "Unknown tool";
          toolResults.push({ type: "tool_result", tool_use_id: block.id, content: result });
        }
      }
      messages.push({ role: "user", content: toolResults });
    } else {
      return response.content
        .filter((b) => b.type === "text")
        .map((b) => b.text)
        .join(" ");
    }
  }
  return "Sorry, I'm having trouble processing that.";
}

app.post("/webhook", async (req, res) => {
  if (req.body.channel !== "voice") return res.status(200).send("OK");

  const transcript = req.body.data?.transcript || "";

  res.setHeader("Content-Type", "application/x-ndjson");

  // Immediately tell the caller we're working on it
  res.write(JSON.stringify({ text: "Let me check on that.", interim: true }) + "\n");

  // Now run the slow tool calls (LLM + external APIs)
  try {
    const answer = await runToolCall(transcript);
    res.write(JSON.stringify({ text: answer }) + "\n");
  } catch (err) {
    res.write(JSON.stringify({ text: "Sorry, I ran into a problem." }) + "\n");
  }
  res.end();
});

app.listen(3000);