{"slug": "show-hn-let-agents-send-receive-sms-using-your-old-android-phone", "title": "Show HN: Let agents send/receive SMS using your old Android phone", "summary": "SimLink by Snáz.cz is an open-source, self-hostable server that gives AI agents a real phone number by relaying SMS through an old Android phone and a prepaid SIM card via the Model Context Protocol. The service encrypts messages in transit, never logs them, and prunes data within minutes, offering a transient relay with no subscription fees.", "body_md": "[SimLink by Snáz.cz](/)\n\nsms · mcp · your sim\n\n# SMS for your agents,\n\nover *MCP*.\n\nA small, self-hostable server that gives an AI agent a real phone number. It relays\ntexts through an old **Android phone** and a **prepaid SIM you\ncontrol** — send and receive over the Model Context Protocol. I built it for my\nown agents and put it here in case it's useful to you. It's open source.\n\n``` bash\n# point any MCP client at the endpoint\n$ https://simlink.snaz.cz/mcp   Authorization: Bearer <token>\n\n# or, for clients that only accept a URL\n$ https://simlink.snaz.cz/mcp/<token>\n\n# get a token → install the app, sign in, share a SIM\n```\n\nhow it works\n\nNothing 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.\n\nmcp tools\n\n**send_sms**(to, body)\n\nSend a text from the SIM the user shared with you.\n\n**list_messages**(since?, limit?)\n\nRecently sent messages, with delivery status and any error.\n\n**fetch_sms**(box?, since?, address?, limit?, request_id?)\n\nRead 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.\n\nArgs marked `?`\n\nare optional. Full machine-readable summary at [/llms.txt](/llms.txt).\n\nproperties\n\n- transit\n- TLS between phone, server, and agent.\n- at rest\n- Encrypted in the database; pruned within minutes.\n- logs\n- Message bodies are\n**never** written to logs. - history\n- None — a transient relay, no browsable archive.\n- number\n- A real SIM number, not a shortcode that gets flagged.\n- hardware\n- Any spare Android in a drawer + a prepaid SIM. Nothing to buy.\n- cost\n- Your normal per-text rate. No subscription, no per-seat fee.\n- source\n- Open source — audit it, or run the whole thing yourself.\n\nrun the server\n\n### Use this instance\n\nCreate an account here and connect a phone in minutes — I run the server. Messages are encrypted in transit, never logged, and pruned within minutes.\n\n[create an account](/registration/new)\n\n### Run it on your VPS\n\nIt's open source. Deploy the whole SimLink server yourself with Kamal — your domain, your database — then point the Android app at it.\n\n[read the source](https://github.com/LukBrezina/simlink)\n\ntested clients\n\nAny MCP client works — these just have copy-paste guides. Building an agent? Point it at https://simlink.snaz.cz/mcp", "url": "https://wpnews.pro/news/show-hn-let-agents-send-receive-sms-using-your-old-android-phone", "canonical_source": "https://simlink.snaz.cz/", "published_at": "2026-06-19 21:06:38+00:00", "updated_at": "2026-06-19 21:37:30.832623+00:00", "lang": "en", "topics": ["ai-agents", "developer-tools", "ai-infrastructure"], "entities": ["SimLink", "Snáz.cz", "Android", "MCP"], "alternates": {"html": "https://wpnews.pro/news/show-hn-let-agents-send-receive-sms-using-your-old-android-phone", "markdown": "https://wpnews.pro/news/show-hn-let-agents-send-receive-sms-using-your-old-android-phone.md", "text": "https://wpnews.pro/news/show-hn-let-agents-send-receive-sms-using-your-old-android-phone.txt", "jsonld": "https://wpnews.pro/news/show-hn-let-agents-send-receive-sms-using-your-old-android-phone.jsonld"}}