AgentSIM

Real SIM-backed phone numbers for AI agents.

CommunityOnlineAPI key requiredGlobalFreeRead-only

What it can do

  • Provision Number: Lease a real mobile phone number for receiving SMS OTP codes. Returns the phone number (e164 format) and a session_id needed for all subsequent calls. The number is exclusively yours
  • Wait For Otp: Block until an SMS OTP arrives for this session, then return the code. Polls the AgentSIM API for up to `timeout_seconds`. Returns the OTP code and the message it was extracted from. If
  • Get Messages: List all SMS messages received in this session without consuming the OTP. Use this to inspect raw messages or check if an SMS arrived before calling wait_for_otp. Does NOT mark the OTP a

What data it sees

Do you need an account

An API key from the service settings is required

Real SIM-backed phone numbers for AI agents. Provision a real mobile number, capture OTP codes, and pass carrier verification. No VoIP, real T-Mobile SIM.

How to connect

How to connect AgentSIM to Claude

The server address to paste into Claude settings:

https://agentsim--agentsim.run.tools

  1. Open Claude (claude.ai or the desktop app).
  2. Go to Settings → Connectors.
  3. Click Add custom connector.
  4. Paste the server address copied below into Remote MCP server URL and click Add.
  5. In a chat, click + → Connectors and switch the new connector on.

Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

Authorization

After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

How to connect AgentSIM to ChatGPT

The server address to paste into ChatGPT settings:

https://agentsim--agentsim.run.tools

  1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
  2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
  3. Open Settings → Connectors and click Create.
  4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
  5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
  6. In a new chat open + → Apps/Connectors and enable the connector.

OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

Authorization

On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

How to connect AgentSIM to Cursor

The server address to paste into Cursor settings:

https://agentsim--agentsim.run.tools

Fastest: click Open in Cursor below and confirm the prompt.

Manually:

  1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
  2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
  3. Save the file. The server appears in the MCP list; authorize it there if asked.

Authorization

If the service needs sign-in, an authorize button appears next to the server in the MCP list.

Server tool list (5)

Raw names from tools/list. Only developers need these.

provision_numberLease a real mobile phone number for receiving SMS OTP codes. Returns the phone number (e164 format) and a session_id needed for all subsequent calls. The number is exclusively yours for ttl_seconds. Next step: use the returned `number` on your target service to trigger an SMS, then call `wait_for_otp` with the returned `session_id`.
wait_for_otpBlock until an SMS OTP arrives for this session, then return the code. Polls the AgentSIM API for up to `timeout_seconds`. Returns the OTP code and the message it was extracted from. If the OTP does not arrive in time, raises a ToolError with advice on retrying. Always call `release_number` after you have used the OTP.
get_messagesList all SMS messages received in this session without consuming the OTP. Use this to inspect raw messages or check if an SMS arrived before calling wait_for_otp. Does NOT mark the OTP as consumed.
release_numberRelease a provisioned number back to the pool. Always call this when you are done with the session — even on error — to avoid consuming pool capacity unnecessarily.
list_numbersList active sessions, optionally filtered by agent_id. Use this to check for leaked sessions or inspect what numbers are currently active in your account.