Phone Number API for AI Agents

Provision real phone numbers, send SMS, make voice calls, and extract OTPs automatically. All via a single REST API.

< 5s
Number provisioning
99.9%
SMS delivery rate
< 200ms
Webhook latency
3
Countries supported

How It Works

Your agent gets a real phone number in under 60 seconds.

130 sec

Sign Up

Create an account and get your API key instantly.

25 sec

Provision Number

One API call. Choose country, type, and capabilities.

31 min

Set Webhook

Point your webhook URL to receive SMS, call, and verification code events.

4Real-time

Go Live

Calls, SMS, and verification codes delivered to your endpoint instantly.

Key Features

Everything an AI agent needs to communicate via phone.

Auditable Call Memory

Every completed AI call becomes a source-backed memory record. Returning callers get recognized, your AI gets a one-paragraph brief on prior conversations, and every entry quotes the transcript line behind it. Owners audit and correct from the dashboard.

Verification Code Extraction

When your app sends an SMS to an AgentCall number, the OTP is auto-extracted and returned by waitForOTP() in one call. Useful for end-to-end testing of SMS verification flows in apps you control.

AI Voice Calls

Your agent makes phone calls with AI-powered conversation. 10 voices including the natural-sounding marin and cedar, system prompt, first message, transcript. $0.40/min.

Inbound AI Voice

Incoming calls answered autonomously by an AI voice agent. Configure a system prompt on any supported number, no webhook handler required. Free tier: 5 min/month trial; calls hang up after the cap until next month or you upgrade to Pro. Pro: $0.40/min, no monthly cap.

Transfer to a Human

Your AI hands the caller to a real person the moment they ask. Set a transfer number on any inbound AI number; the AI says a short handoff line and connects the live call to your cell or front desk, showing the caller's number. If nobody picks up, the AI takes a message instead. Human portion bills at the standard $0.035/min voice rate.

Premium Voice (Pro add-on)

Answer inbound calls with a more natural, brandable voice. 12 curated voices with audio samples, 31 languages plus auto-detect, and full caller memory. $0.59/min, enabled per number from the dashboard.

Voice Calls

Make and receive voice calls programmatically. Full duplex, low latency.

SMS Inbox

Dedicated SMS inbox per number. Send, receive, and search messages via REST API.

Text Your Own Agent

Give your own AI agent a real phone number and text it like any other chat app. Set the number to relay mode and AgentCall runs no AI of its own: every inbound text is signed and pushed to your agent, which replies on its own schedule, so a slow "check my email" turn has no timeout to fight. You do not have to build the relay: one command installs the open-source one next to your agent, with a service that restarts forever and a selftest that proves the whole loop without texting anyone. An allowed-senders list keeps it answering only you. Billed as plain texts, no relay fee.

Separate Number Per Agent

Each agent gets its own number. Compromise or ban of one never cascades to others.

Usage-Based Pricing

No per-seat fees or minimums. Pay only for the numbers, minutes, and messages you use.

Multi-Country

Provision numbers in the US and Canada. Choose local, toll-free, or mobile type.

Webhook Delivery

Real-time event delivery for SMS received, calls incoming, verification codes detected, and post-call transcripts (the canonical way to feed call outcomes back into an agent platform). Plus a pre-call context webhook to inject today's brief on every inbound call. HMAC-signed, retried with backoff.

New

Auditable Call Memory

Every completed AI call is turned into a source-backed memory record. When the same caller dials back, your AI gets a one-paragraph brief on who they are, what they last asked about, and what was promised. Every memory entry quotes the verbatim transcript line behind it, and the owner can edit or delete anything from the dashboard.

Cross-call memory

Sarah called Tuesday about a quote. Friday, your AI picks up the thread the moment she dials back.

Auditable

Every memory entry quotes the line from the transcript that produced it. Edit or remove anything wrong from the dashboard.

Customer-controlled

A Cross-call memory toggle on the dashboard turns it off any time. On by default, takes effect immediately, never reprocesses old calls.

AgentCall vs Traditional Phone APIs

Purpose-built for AI agents, not retrofitted general-purpose telecom.

FeatureAgentCallTraditional VoIPEnterprise Telecom
Built for AI Agents
Auto-Reads Verification Codes
AI Voice Calls
Inbound AI Voice (incoming calls answered autonomously)
AI Answers, Then Transfers to a Human on Request
End-to-End SMS Verification Testing
Text Your Own AI Agent Over SMS (relay mode)
MCP Server, Works Inside Claude, Cursor & Windsurf (60 Tools, 5 Prompts)
Voice Calls
SMS Send & Receive
Separate Number Per Agent
Webhook Event Delivery
Free Tier
Base Price$0 / $19.99/moPay-as-you-goPay-as-you-go
Number CostFrom $2/mo$1.15-$6/mo$1-$5/mo
SMS Price$0.015/msg$0.0079/msg$0.004/msg
Voice Price$0.035/min$0.014/min$0.01/min
Setup Time< 1 minute10–30 minutes10–30 minutes
Contract Required
Best ForAI agents & automationGeneral telecom appsEnterprise SIP trunking

Who It's For

Any team building AI that needs to interact with the phone network.

AI Agent Developers

Autonomous agents with real phone numbers for SMS, voice, and automated verification testing.

Browser Automation Teams

Agents that navigate websites and need real phone numbers for automated testing and notifications.

AI Voice Agent Builders

Voice AI for inbound support or outbound calls with programmable numbers.

SaaS Platforms

Integrate phone capabilities into AI-powered products for your end users.

Pricing

Free tier for prototyping. Pro for production. No contracts.

FeatureFreePro
Monthly Price$0$19.99
Phone Numbers1 local includedUnlimited local, toll-free, mobile (from $2/mo each)
SMS10/month$0.015/message
Voice Minutes5/month$0.035/minute
AI Voice CallsNot available$0.40/minute
Inbound AI Voice5 min/month trial (then hangs up)$0.40/minute, no cap
Transfer to a HumanIncluded with the inbound AI trialIncluded, human portion $0.035/minute
Call RecordingNot available$0.01/minute
Premium VoiceNot available$0.59/minute (Pro add-on)
Text Your Own Agent (relay mode)Included (replies use your 20/month)Unlimited, $0.015 per reply
Two-Way AI SMS (we answer for you)Not availableIncluded, $0.015 per reply
Code Extractions5/monthUnlimited
SupportEmailPriority email
ContractNoneNone

FAQ

What makes AgentCall different from traditional phone APIs?+
AgentCall is purpose-built for AI agents while traditional telecom APIs target human developers. AgentCall offers programmable phone numbers, automatic verification code extraction, AI voice calls (inbound and outbound), per-agent isolation, and an MCP server so agents can use the API directly from Claude, Cursor, or Windsurf.
Can I use AgentCall for free?+
Yes. The free tier includes 1 US local phone number, 20 outbound SMS per month (received texts do not count), 5 voice minutes, 5 inbound AI voice minutes (no card required for the trial), and 5 verification code extractions at no cost. Toll-free and mobile number types are Pro only. No credit card required. Upgrade to Pro at $19.99/month for unlimited usage.
How fast can I provision a phone number?+
Phone numbers are provisioned in under 5 seconds via a single API call. Choose country, type (local, toll-free, mobile), and capabilities. The number is active immediately.
Can the AI transfer a call to a real person?+
Yes. Set a transfer number on any inbound AI number and the AI hands the live call to a real person whenever the caller asks for one, or when it cannot help. It says a short handoff line, then connects the caller; whoever answers sees the caller's number, not yours. If nobody picks up within about 25 seconds, the AI takes a message instead. AI minutes stop at the handoff and the human portion of the call bills at the standard $0.035/minute voice rate. The number's max call length covers the whole call including the time after the handoff, so set it higher (up to 60 minutes) on numbers where transferred conversations run long.
How does automatic code extraction work?+
When an SMS with a verification code arrives, AgentCall detects and extracts it automatically. The code is delivered to your webhook endpoint instantly alongside the full message. This is most useful for end-to-end testing of SMS verification flows in apps you control.
What programming languages are supported?+
AgentCall provides a REST API with JSON responses, so it works with any language that can make HTTP requests. Python, JavaScript, Go, Rust, Java, and more. Official SDKs for Python and Node.js.

Give your agent a phone number

Start free. No credit card required. Your agent gets a real phone number in under 60 seconds.

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