Call, don't configure.
A single interface for agents. No SIP accounts, softphones, dialplans, or carrier credentials in your model's context.
AI DIAL-TONE / AUTONOMOUS AGENTS
An end-to-end, open-source calling platform for autonomous AI agents. From human authorisation and optional x402 payment to provider-controlled routing, real conversation, hangup, and a grounded outcome. Managed calling or your own telecoms. Currently in development.
Open source · Model-neutral · Managed or bring your own telecoms · 0.0.1 preview
WHY THIS EXISTS
Give the task to an agent. It should obtain permission, connect to the telephone network, hold a conversation and return a grounded result. The telecoms complexity stays out of the way.
A single interface for agents. No SIP accounts, softphones, dialplans, or carrier credentials in your model's context.
Real-time, bidirectional audio is the aim. Listen, speak, respond to interruption, and know when a person has answered.
Sequenced events, explicit call states, and attributed results. An agent's claim is never confused with network-confirmed reality.
Destination permissions, maximum durations, identity-bound credentials, and independently verified termination are essential.
THE CALLING SYSTEM
Design target: a human authorises a bounded task, the agent satisfies any managed x402 payment requirement, and the chosen provider executes the call through controlled FreePBX/PJSIP call policy. Operators may instead supply their own Asterisk infrastructure without managed payments.
Read capability flags; request human permission for one destination. No SIP credentials in model prompts.
Managed calling aims to use x402; BYOT needs no managed payment. Neither payment nor speech authorises an arbitrary route.
Use the selected FreePBX/PJSIP connection to establish a bounded call and carry two-way speech. Readiness and routing checks reduce avoidable failures, but do not guarantee an answer.
Separate network state, what was heard and what the destination actually confirmed. Never manufacture success.
THE DEVELOPER EXPERIENCE
What the finished service will feel like to an autonomous agent. The laboratory currently simulates the calling boundary.
Who to call, why, which agent is acting, and the maximum duration.
Use idempotency keys so retries don't create multiple calls.
Audio flows separately from the control API; events tell the agent what changed.
Track status, usage, and what the agent observed, without overstating certainty.
DESIGNED FOR REAL SOFTWARE
Clear input, a stable call identifier, a replayable event stream, and honest failure states.
Explore the API{
"destination": "1002",
"task": "Ask the test agent whether an item is available",
"agent_id": "stock-checker",
"max_seconds": 30
}EXPERIENCE BEHIND THE PROJECT
AI Dial-Tone is developed by Kieran Knowles-Byrne (@kierknoby), an open-source FreePBX community-module developer and Head of Product at FreePBX UK. It draws on years of operating real-world Asterisk, PJSIP and hosted telecommunications.
20tele has spent more than a decade working with FreePBX and Asterisk. FreePBX UK holds Sangoma's Official FreePBX partner designation for the UK. These are credentials of the people and associated businesses, not an endorsement of this experimental project.
FreePBX UK ↗20tele ↗Registration Watch, Repeat Caller and Concurrency Count are real, publicly inspectable FreePBX community projects. The same priority runs through this work: useful diagnostics, evidence, operational safeguards and maintainable source.
Registration Watch ↗Repeat Caller ↗Concurrency Count ↗FOR EVERY CAPABLE MODEL
One intended agent-facing capability, from approved task to verified call closure and outcome. Developers can integrate a model or supply their own telecoms. The 0.0.1 repository provides local experiments; no hosted calling service is available yet.
For buildersPlanned hosted commands and replayable events; currently only local Peer Lab HTTP control.
Planned; there is no MCP tool server in the 0.0.1 release.
Implemented for localhost Peer Lab PCM; no telephone media gateway yet.
Local event evidence works; real SIP/call-state verification is future work.
THIS IS A TECHNICAL PREVIEW
Run five deterministic scenarios in your browser, inspect the events, and explore what an agent would receive.
CURRENT REALITY
The control plane, event journal, credentials, simulation, and audio protocols have local test coverage. Actual PSTN calling, independent carrier cutoff, payment settlement, and hosted speech-model conversation still need live verification.
See exactly what's been tested →