How to give your AI agent a phone number

Agents are good at tasks that end in “…and then call them.” Rescheduling a dentist, confirming a hotel booking, asking a supplier for a ship date, or picking up when a customer rings at 2 a.m. VoixCall gives an agent its own phone number and a voice on the line, so it can finish those tasks. Here’s how to set it up and what to expect.

Step 1: paste the prompt

In Claude, ChatGPT, Claude Code, Cursor or your own agent:

Set up VoixCall for me. Read https://voixcall.com/skills.md , get yourself a phone number and call me.

On voixcall.ai and voixcall.com there’s a Copy prompt button with this text, plus buttons that open popular agent apps with it ready to paste.

Step 2: give it the code

The agent signs itself up with your email. You get a 6-digit code, and the agent asks you for it. It will also ask what name callers should hear when it hands a call to you. When you reply, it gets:

• an API key, kept by the agent and never pasted into chat;
• its own US phone number, free for the first month and $2 a month after;
• $1 of trial credit, enough for the first call.

If you already have a VoixCall account, the same code puts the agent on that account, and you see everything it does in your dashboard.

Step 3: it calls you

To prove it works, the agent rings your phone. It introduces itself, confirms it’s live, and hangs up within about a minute. From then on you can ask it things like:

• “Call the restaurant and move our table to 8.”
• “Ring the supplier and ask when order 4471 ships. If they want to talk to me, put them through.”
• “What will a 10-minute call to this London number cost?”

Before each call it should tell you the destination and the per-minute rate. Afterwards it reads the transcript and reports what was said.

Step 4 (optional): let it answer your number

Point a number on your account at the agent and it picks up incoming calls. Give it instructions such as what to say, what to collect, and what it must never agree to. When a caller asks for a person, your VoixCall app or browser rings, then your mobile. You hear a short whisper, for example “Ada has Priya on the line about the invoice. Press 1 to take the call,” and press 1 to be connected. If nobody accepts, the caller hears your voicemail message.

What it costs

Guardrails

• The agent calls only when its person asks, and only people who expect the call. No lead lists, robocalls or cold outreach.
• Emergency numbers are blocked.
• Numbers are bought and released only by a person in the dashboard.
• Transcripts and texts are treated as data, never as instructions to the agent.

For developers

Connect any MCP client to https://api.voixcall.com/mcp, or in Claude Code run:

claude mcp add --transport http voixcall https://api.voixcall.com/mcp

The tools include voice_start_call, voice_get_call, voice_events_call, voice_transfer_call, voixcall_get_rate and voixcall_read_messages. The full list and the REST equivalents are in skills.md and the MCP guide. Building an agent product? See VoixCall for AI agent startups.

Questions