Real-world applications
What you can build
with ReachCell
Six production-ready patterns using real carrier phone numbers — for verification, automation, and AI agents.
Confirm a phone number is real, live, and reachable
Carrier-trusted OTP & 2FA delivery
Verizon, AT&T, and T-Mobile silently filter SMS from VoIP-originated numbers when they carry one-time passcodes. Your Twilio or AWS SNS OTP lands in a grey zone — sometimes filtered, sometimes delayed. Because every ReachCell number is a physical SIM on a carrier plan, it is treated the same as a consumer device texting a friend.
Use this for login codes, transaction confirmations, password resets, and any message that must reach the recipient on the first attempt.
POST /v1/sms/send Authorization: Bearer ak_live_•••••••• { "from": "+14155552671", "to": "+12125559876", "body": "Your login code is 4821. Valid for 5 min." } // Response — queued to real SIM immediately { "id": "msg_01abc...", "status": "queued" } // Delivered webhook fires when carrier confirms { "event_type": "sms.delivered", "data": { "id": "msg_01abc..." } }
Missed-call number verification
Dial a user's number from your provisioned SIM. Their phone rings. They never answer. Your server receives a call.missed webhook — the number is confirmed live and reachable. Zero cost to the user, zero app installs, no SMS credit consumed.
Works the other way too: give users a number to call. They ring it, you answer with call.missed, their number is captured automatically — no form entry needed. Popular in markets where per-SMS cost is significant, but useful anywhere zero-friction matters.
// 1. Place the call — they see your number ring POST /v1/calls/dial { "to": "+12125559876" } // 2. Webhook fires automatically — no answer needed { "event_type": "call.missed", "data": { "to": "+12125559876", "status": "missed", "cost_usd": 0.004 } } // → mark number as verified in your DB
Reliable two-way SMS with a number your customers recognize
Two-way SMS automation
Register a webhook for sms.received. Every time a customer texts your number, your backend is notified in real time with the sender's number and message body — no polling, no delay. Reply instantly via the API.
SMS has a 98% open rate vs. 20% for email. Use this pattern to power customer support bots, order status queries, subscription management ("text STOP"), lead qualification, and survey flows — all over the channel your customers already have open.
// Webhook payload — customer texted you { "event_type": "sms.received", "data": { "from": "+12015550143", "to": "+14155552671", "body": "What's my order status?" } } // Your handler: look up order, then reply POST /v1/sms/send { "from": "+14155552671", "to": "+12015550143", "body": "Your order #4821 ships tomorrow." }
Appointment reminders with reply parsing
Send automated reminders 24 hours before a scheduled appointment. Because the message comes from a real local number, patients and customers can reply naturally — "YES", "CANCEL", or a question — and your sms.received handler updates the booking system automatically.
Because you control the SIM, message content never passes through a third-party's logging infrastructure. Important for healthcare providers who need to avoid storing PHI in vendor systems outside their control.
// Scheduler fires 24 h before slot POST /v1/sms/send { "from": "+15105552300", "to": "+16505558821", "body": "Reminder: Dr. Chen, tomorrow 10am.\nReply YES to confirm or CANCEL to cancel." } // Patient replies — sms.received webhook fires { "event_type": "sms.received", "data": { "from": "+16505558821", "body": "YES" } } // → update appointment status to "confirmed"
React to inbound calls in real time — no telephony platform needed
Missed-call callback queue
When a customer calls your support number and no agent is available, ReachCell fires a call.missed webhook with the caller's number. Your system immediately texts them back — "Sorry we missed you, we'll call within 15 minutes" — then adds them to a callback queue.
The same pattern handles overflowed inbound calls during peak periods, after-hours coverage, and outbound sales dialing — triggering an automated SMS follow-up when the prospect doesn't answer.
// Webhook fires when customer's call goes unanswered { "event_type": "call.missed", "data": { "from": "+13105550088", "to": "+14155552671", "direction": "inbound" } } // Your handler: SMS them back + queue for callback POST /v1/sms/send { "from": "+14155552671", "to": "+13105550088", "body": "We missed your call. An agent will call you back within 15 min." } // + enqueue { from: "+13105550088" } in your CRM
Give your AI agents a real phone number — without writing API integrations
AI agents with native phone access
ReachCell ships a Model Context Protocol (MCP) server that plugs directly into Claude Desktop, Claude Code, and any MCP-compatible agent runtime. Your AI can send SMS, dial numbers, check call status, and query account balance — natively, using tool calls, with no glue code.
Tell Claude "verify this customer's number via missed call" and it will dial them, wait for call.missed, and confirm — handling the full multi-step flow autonomously. Or "send the team a status update" — Claude picks the right number and sends it. Available on Growth and Scale plans.
// You: "Send the weekly report to Sarah at +16505551234" // Claude calls the MCP tool automatically: send_sms({ from: "+14155552671", to: "+16505551234", body: "Weekly report: 1,240 messages sent,\n$12.40 cost, 99.2% delivery rate." }) // Claude: "Done — message delivered to Sarah." // MCP tools available: send_sms · get_sms_status // dial_number · hangup_call · get_call_status // list_phone_numbers · get_account_balance
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