Pro Feature

AI Voice Calls for AI Agents

Your agent makes real phone calls with AI-powered conversation. Provide a system prompt, pick a voice, and the AI handles the entire call, then returns a full transcript.

Your AI receptionist now remembers callers between calls. When a returning caller dials in, your AI gets a one-paragraph brief with what they last asked about and what was promised. Source-backed, customer-controlled. Read about Auditable Call Memory.

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10
AI voices
$0.40
Per minute
10 min
Default max duration
< 1s
Call connect time

How AI Voice Calls Work

Three inputs, one API call. The AI handles everything else.

1

Set the Prompt

Write a system prompt: "You are calling to schedule a dentist appointment for Tuesday afternoon."

2

Pick a Voice

Choose from 10 distinct AI voices. Soft and natural, professional, warm, energetic, or calm.

3

AI Makes the Call

The AI dials the number, speaks, listens, and responds in real-time. Fully autonomous.

4

Get the Transcript

When the call ends, get a full transcript with timestamps, speaker labels, and a summary.

10 AI Voices

Each voice has a distinct personality. Marin and Cedar are the newest natural-sounding picks. Click to preview the original 8, then pick the one that fits your use case.

Marin

New

Soft & Natural

Light, friendly tone that sounds like a real person on the line.

Best for: Receptionist, support, conversational

Cedar

New

Warm & Grounded

Even, thoughtful cadence with a hint of warmth.

Best for: Advisory, healthcare, trust-building

Shimmer

Bright & Energetic

Long-running default. Upbeat and enthusiastic, great first impression.

Best for: Sales, outreach, receptionist

Sage

Calm & Authoritative

Steady, reassuring, and knowledgeable.

Best for: Healthcare, finance

Ash

Warm & Conversational

Friendly tone that puts people at ease.

Best for: Customer service

Ballad

Expressive & Melodic

Dynamic range with natural inflection.

Best for: Engaging conversations

Coral

Clear & Professional

Crisp, business-appropriate delivery.

Best for: B2B calls

Echo

Resonant & Deep

Authoritative presence with depth.

Best for: Formal inquiries

Verse

Smooth & Articulate

Polished and refined delivery.

Best for: Executive communication

Alloy

Neutral & Balanced

Clean, clear, works for any scenario.

Best for: General purpose

One API Call to Make a Call

Or use the initiate_ai_call MCP tool from Claude Desktop, Cursor, or OpenClaw.

POST /v1/calls/ai
{
  "from": "num_abc123",
  "to": "+14155551234",
  "systemPrompt": "You are calling Joe's Pizza to order a large pepperoni pizza for pickup. Ask about the wait time.",
  "voice": "ash",
  "firstMessage": "Hi! I'd like to place an order for pickup please.",
  "maxDurationSecs": 300
}
GET /v1/calls/:callId/transcript
{
  "callId": "call_x7k9m2",
  "duration": 47,
  "entries": [
    { "role": "assistant", "text": "Hi! I'd like to place an order for pickup please.", "timestamp": "00:00" },
    { "role": "user", "text": "Sure! What can I get for you?", "timestamp": "00:03" },
    { "role": "assistant", "text": "I'd like a large pepperoni pizza. How long is the wait?", "timestamp": "00:05" },
    { "role": "user", "text": "About 20 minutes for a large pepperoni.", "timestamp": "00:09" },
    { "role": "assistant", "text": "Perfect, I'll pick it up in 20 minutes. Thank you!", "timestamp": "00:12" }
  ],
  "summary": "Ordered a large pepperoni pizza for pickup. Wait time: 20 minutes."
}

Use Cases

Any scenario where your AI agent needs to have a phone conversation.

Appointment Scheduling

Schedule dentist visits, doctor appointments, hair salons, auto repairs. The AI negotiates time slots and confirms details.

Lead Qualification

Call inbound leads, ask qualifying questions, and log structured data. Filter out unqualified prospects automatically.

Customer Follow-ups

Call customers after a purchase, appointment, or support ticket. Collect feedback and satisfaction scores.

Business Information Gathering

Call restaurants, stores, or offices to ask about hours, availability, pricing, or policies.

Order Status Checks

Call shipping companies, pharmacies, or service providers to check on order or delivery status.

Survey & Research

Conduct phone surveys at scale. The AI asks questions, records answers, and produces structured results.

What You Get

Everything built into every AI voice call.

Full Transcripts

Every call produces a complete transcript with timestamps, speaker labels (assistant vs callee), and an AI-generated summary.

Custom System Prompts

Tell the AI exactly what to do: schedule an appointment, ask about hours, place an order, gather information. Any scenario.

Configurable First Message

Control what the AI says first when the call connects. Set the tone from the opening line.

Duration Controls

Set maximum call duration (default 10 minutes, up to 60 minutes). The AI wraps up the conversation cleanly before time runs out.

MCP Tool Integration

Use the initiate_ai_call tool directly from Claude Desktop, Cursor, Windsurf, or OpenClaw. No REST calls needed.

Real Phone Numbers

Calls come from your provisioned AgentCall number, with a stable caller ID for the duration of the call.

Pricing

Simple per-minute pricing. No hidden fees.

$0.40/minute

Includes carrier charges + AI processing. Pro plan required ($19.99/month base).

10 AI voices included
Full transcripts with every call
Custom system prompts
Up to 60 minutes per call
No per-call fees — only pay for minutes used
Provisioned number required (from $2/mo)

Frequently Asked Questions

What are AI voice calls?+
AI voice calls let your AI agent make real phone calls where the AI handles the entire conversation autonomously. You provide a system prompt with instructions, choose a voice, and the AI speaks, listens, and responds in real-time. When the call ends, you get a full transcript.
How do I make an AI voice call?+
Send a POST request to /v1/calls/ai with your provisioned number, the destination number, a system prompt, and optionally a voice and first message. Or use the initiate_ai_call MCP tool from Claude Desktop, Cursor, or OpenClaw — just say "Call +15551234567 and ask about their business hours."
What voices are available?+
10 voices: Marin (soft, natural), Cedar (warm, grounded), Shimmer (energetic, long-running default), Sage (calm), Ash (warm), Ballad (expressive), Coral (professional), Echo (deep), Verse (smooth), and Alloy (neutral). Preview each at /v1/calls/voices.
Can I get a transcript afterward?+
Yes. Every AI voice call produces a full transcript with timestamped conversation entries, speaker labels, and a summary. Access it via GET /v1/calls/:callId/transcript or the get_call_transcript MCP tool.
How long can a call last?+
Default maximum is 10 minutes (600 seconds). You can set maxDurationSecs up to 3600 (60 minutes). The AI wraps up the conversation before time runs out.
Do I need a special number for AI voice calls?+
You need any provisioned AgentCall number. Local numbers ($2/mo), toll-free ($2.50/mo), and mobile ($2/mo) all work. Pro plan is required for AI voice calls.
Can my OpenClaw agent make AI voice calls?+
Yes. With the AgentCall environment variables set, your OpenClaw agent can make AI voice calls by just saying "Call +15551234567 and schedule an appointment." The agent uses the POST /v1/calls/ai endpoint automatically.

Let your agent make the call

Sign up free, provision a number, and make your first AI voice call in under 2 minutes.

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