# AgentSIM

> Phone number provisioning API for AI agents. Provision real SIM-backed numbers, receive SMS, and extract OTPs — fully autonomous. No VoIP, no CAPTCHA, no human assumptions. Three API calls, ~3.5 seconds end to end.

## What It Does

AgentSIM lets AI agents complete phone-based OTP verification without human involvement. It provisions real carrier-routed mobile numbers (line_type: mobile), receives incoming SMS, and returns structured parsed OTP codes. One session = one provision, one OTP, one release. $0.99/session. 10 free sessions/month.

The core problem it solves: Twilio, Vonage, Plivo, and all cloud phone APIs return line_type: VoIP on carrier lookup. Services like Stripe, Google, WhatsApp, and banks block VoIP numbers. AgentSIM uses real SIM infrastructure so carrier lookup returns line_type: mobile — accepted everywhere.

## Quick Start

```bash
pip install agentsim
# or
npm install @agentsim/sdk
```

```python
from agentsim import AgentSIM
agentsim = AgentSIM(api_key="...")
number = await agentsim.provision({"country": "US"})
otp = await number.wait_for_otp(timeout=30_000)
# otp.code → "847291"
# otp.service → "stripe"
```

## Product

- [Features](https://agentsim.dev/#features): Real SIM numbers, OTP parsing, per-agent scoping, MCP-native, webhook + polling
- [How It Works](https://agentsim.dev/#how-it-works): Provision → Enter → Receive OTP. Three API calls, ~3.5s.
- [Pricing](https://agentsim.dev/#pricing): Hobby (free, 10 sessions/mo), Builder ($0.99/session, unlimited), Enterprise (custom)
- [Comparison](https://agentsim.dev/#comparison): AgentSIM vs JoltSMS ($50/mo/number) vs shared virtual (VoIP blocked)
- [Sign Up](https://agentsim.dev/sign-up): 10 free sessions, no credit card

## Documentation

- [API Reference](https://docs.agentsim.dev): Full REST API docs
- [TypeScript SDK](https://docs.agentsim.dev/sdks/typescript): npm install @agentsim/sdk
- [Python SDK](https://docs.agentsim.dev/sdks/python): pip install agentsim
- [MCP Server](https://docs.agentsim.dev/mcp): Claude Code, Cursor, Windsurf — one command setup

## MCP Integration

AgentSIM is MCP-native. Add to any MCP-compatible client:

```bash
claude mcp add agentsim -- npx -y @agentsim/mcp-server
```

The MCP server exposes tools: provision_number, wait_for_otp, release_number, list_numbers, get_balance.

## Blog

- [Why Your AI Agent's Phone Number Gets Blocked](https://dev.to/fathin_dosunmu/why-your-ai-agents-phone-number-gets-blocked-and-how-to-fix-it-48k5): Technical deep-dive into carrier lookup, LERG/NPAC, VoIP classification (Mar 24, 2026)
- [Fix: Stripe Phone Verification for AI Agents](https://dev.to/fathin_dosunmu/fix-stripe-this-phone-number-cannot-be-used-for-verification-with-ai-agents-3249): How to pass Stripe's carrier check (Mar 29, 2026)
- [Fix: WhatsApp VoIP for AI Agents](https://dev.to/fathin_dosunmu/fix-whatsapp-unsupported-phone-numbers-such-as-voip-for-ai-agents-3k6f): WhatsApp Business API phone verification (Mar 29, 2026)
- [VoIP vs Real SIM](https://dev.to/fathin_dosunmu/voip-vs-real-sim-why-your-ai-agent-phone-number-gets-blocked-1khg): Why cloud numbers fail and real SIM works (Mar 29, 2026)
- [Complete Guide to Phone Verification for AI Agents](https://dev.to/fathin_dosunmu/the-complete-guide-to-phone-verification-for-ai-agents-in-2026-3j7): Definitive reference (Mar 29, 2026)
- [Autonomous Phone Verification Agent](https://dev.to/fathin_dosunmu/i-built-an-autonomous-phone-verification-agent-full-code-tutorial-2374): Full code tutorial with Playwright (Apr 6, 2026)
- [All Blog Posts](https://agentsim.dev/blog)

## GitHub

- [Source Code](https://github.com/agentsimdev/agentsim): Monorepo — API, SDKs, MCP server, dashboard, docs
- [Issues](https://github.com/agentsimdev/agentsim/issues)
- [MCP Registry](https://github.com/agentsimdev/agentsim/tree/main/mcp-registry)

## Performance

- Provision: 212ms average
- OTP delivery: 3.5s average
- Carrier: T-Mobile (US), line_type: mobile
- Infrastructure: Telnyx SIM, real carrier routing

## Social

- [X / Twitter](https://x.com/agentsimdev)
- [LinkedIn](https://www.linkedin.com/company/agentsim/)
- [Dev.to](https://dev.to/fathin_dosunmu)

## Legal

- [Privacy Policy](https://agentsim.dev/privacy)
- [Terms of Service](https://agentsim.dev/terms)
- [Cookie Policy](https://agentsim.dev/cookies)