What products is this used with?

PollyReach, Vapi.ai, Retell, Bland.ai, OpenAI Realtime, Anthropic Computer Use, Browserbase, Skyvern, custom AI agents using LangChain or OpenAI function calls, and personal AI assistants that screen calls or schedule meetings.

Guide · AI Agents

The phone number layer for AI agents

Q: Why do AI agents need a real phone number instead of Twilio?

Twilio gives you VoIP numbers that get flagged on Cash App, Coinbase, Tinder, banking apps, Stripe Atlas, and most fraud-detection stacks. For B2B calling (booking, support) Twilio works. For account signups, two-factor verification, or any consumer-facing identity, VoIP numbers fail. Real carrier numbers (AT&T, T-Mobile, MobileX) pass these checks.

Q: How fast can an AI agent get a number via API?

Typically 30-60 seconds from API call to active number. We pool inventory in advance so you're not waiting on carrier-side provisioning per request.

Q: Can the AI agent receive SMS on the number?

Yes — either via webhook (we POST to your URL when SMS arrives) or polling (GET /v1/numbers/:id/messages). Latency from SMS-receive to webhook-delivery is under 3 seconds.

Your AI agent can write code, browse the web, book reservations. Then it hits an account signup screen — Cash App, Coinbase, Tinder, Stripe — and dies on phone verification because Twilio's number is flagged as VoIP. Here's how to fix that with real US carrier numbers via API.

Get API access

First 5 numbers free. ~60 seconds to provision. Built for AI agent platforms.

See the API →

What "real carrier" means and why it matters for AI agents

Every phone number sold by Twilio, Plivo, Telnyx, Bandwidth, or any cloud-telephony provider is technically a VoIP number — registered with carriers but flagged in the FCC's national database as a non-mobile, non-landline endpoint. Modern fraud-detection services (TeleSign, Truecaller, Trust Portal, Stripe Radar, Plaid) read that flag and refuse to send verification SMS to it.

A "real carrier number" is a SIM-card-backed line on AT&T, T-Mobile, MobileX, or Verizon — the same lines a human customer carries in their pocket. To every fraud check, that number is indistinguishable from a real person's phone. Verification SMS arrives. Account signups complete. The AI agent's mission succeeds.

MeiSIM USA provisions these real carrier lines as eSIMs, on demand, via REST API. From your AI agent's perspective: one HTTP call, get a number, use it, receive SMS.

What AI agents actually do with these numbers

Browser agents signing users up. OpenAI Operator, Anthropic Computer Use, Browserbase, Skyvern — the agent fills out a signup form, hits "send verification code," and needs to read the SMS. Our webhook delivers it within 3 seconds.
Voice agents making calls. PollyReach, Vapi, Retell, Bland — your agent calls a restaurant for a reservation. The restaurant sees a real US number on caller ID, not "Unknown VoIP." They pick up.
Multi-agent verification farms. Spinning up dozens of test accounts for QA, each with its own real number. Bulk provisioning API returns up to 1,000 numbers per call.
Personal AI assistants. The user's AI assistant answers calls on their behalf. Caller sees a real number, doesn't hang up thinking it's spam.

Code-level integration

The API is REST + JSON, identical pattern to Stripe's SDK style. Three calls cover 95% of agent workflows:

// 1. Pick a plan GET /mm/products?country=US // 2. Provision a number (returns phone, ICCID, QR, LPA) POST /v1/numbers/provision { "plan_id": "p3:1:123", "label": "agent-cashapp-bot", "webhook_url": "https://your.app/sms" } // 3. Read incoming SMS GET /v1/numbers/{id}/messages

Or use the MCP server with Claude Desktop / Cursor / Zed and skip writing any code at all — the AI client calls the API directly via natural language. See /api-for-ai-agents.html.

Why developers building AI agents pick us over Twilio

Verification success rate: ~98% with our numbers vs ~65% with Twilio (measured across Cash App, Coinbase, Tinder, Stripe Atlas test signups in 2026).
Pricing: $9/number flat. No per-minute charges. No SMS markup. Predictable cost for agent workflows.
Speed: 30-90s API-to-active vs Twilio's instant-but-VoIP. The extra minute matters less than the verification pass-rate.
International payment: We accept USDT, Alipay, WeChat Pay — relevant for AI startups outside the US.

Note: For pure outbound voice (your AI calls humans, no verification), Twilio is still excellent and significantly cheaper at scale. Use both: Twilio for outbound, MeiSIM for inbound/verification. We're not trying to replace Twilio — we're filling the gap they don't cover.

Ready to integrate?

Get an API key today. Five free numbers to test before you commit.

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FAQ

Why do AI agents need a real phone number instead of Twilio?

For B2B calling (booking, support) Twilio works fine. For account signups, two-factor verification, or any consumer identity, VoIP numbers fail because fraud detection blocks them. Real carrier numbers pass.

How fast can an AI agent get a number via API?

30-90 seconds from API call to active number. We pool inventory in advance.

Can the AI agent receive SMS on the number?

Yes. Webhook (we POST when SMS arrives) or polling (GET messages endpoint). <3s latency.

Which AI agent products is this used with?

PollyReach, Vapi, Retell, Bland, OpenAI Realtime, Anthropic Computer Use, Browserbase, Skyvern, plus custom agents via LangChain or OpenAI function calls.

Is there an MCP server?

Yes. npx @meisim/mcp-server exposes all the tools to Claude Desktop, Cursor, Zed, Continue.