sms · mcp · your sim
over MCP.
A small, self-hostable server that gives an AI agent a real phone number. It relays texts through an old Android phone and a prepaid SIM you control — send and receive over the Model Context Protocol. I built it for my own agents and put it here in case it's useful to you. It's open source.
$ https://simlink.snaz.cz/mcp Authorization: Bearer <token>
$ https://simlink.snaz.cz/mcp/<token>
how it works
Nothing in the middle stores your texts. The server holds a message only long enough to hand it from the agent to the phone (or back) — encrypted, never logged, pruned within minutes.
mcp tools
send_sms(to, body)
Send a text from the SIM the user shared with you.
list_messages(since?, limit?)
Recently sent messages, with delivery status and any error.
fetch_sms(box?, since?, address?, limit?, request_id?)
Read SMS already on the phone (inbox/sent). Two-step and non-blocking: start a read, then call again with the returned request_id to collect the rows.
Args marked ?
are optional. Full machine-readable summary at /llms.txt.
properties
- transit
- TLS between phone, server, and agent.
- at rest
- Encrypted in the database; pruned within minutes.
- logs
- Message bodies are never written to logs. - history
- None — a transient relay, no browsable archive.
- number
- A real SIM number, not a shortcode that gets flagged.
- hardware
- Any spare Android in a drawer + a prepaid SIM. Nothing to buy.
- cost
- Your normal per-text rate. No subscription, no per-seat fee.
- source
- Open source — audit it, or run the whole thing yourself.
run the server
Use this instance
Create an account here and connect a phone in minutes — I run the server. Messages are encrypted in transit, never logged, and pruned within minutes.
Run it on your VPS
It's open source. Deploy the whole SimLink server yourself with Kamal — your domain, your database — then point the Android app at it.
tested clients
Any MCP client works — these just have copy-paste guides. Building an agent? Point it at https://simlink.snaz.cz/mcp