Build an AI voice bot like an Express app

If you can write an Express app, you can run a phone system. npm install dialpress, connect to the gateway over gRPC, and every SIP request arrives at a path chosen by the dial plan.

Routes, not state machines

app.register answers phones that sign in. app.message proxies texts to the extension. app.invite dials the extension and sends a 486 when it is busy. Middleware, params, Router() and error handlers work the way they do in Express 5.

The bot is another app

An AI bot connects with pathPrefixes: ['/ai'] and claims those calls. It answers, opens res.media() for the call’s audio, feeds the caller’s PCM to speech recognition, and plays its text-to-speech back in real time — calling clear() when the caller interrupts.

Handoffs keep the call alive

The PBX hands an inbound caller to the bot with res.handoff('/ai/front-desk'). When the caller presses 0, the bot hands the same call back to a person with a summary of what was said. Same call ID, no transfer, no dropped audio.

Fork it

The SDK ships with examples — an echo bot, a messaging bot, SIP to SMS, SIP to email — and a local simulator. Fork one, point it at your gateway, and your stack is on the phone network.