Connect any phone line to any AI model. Self-hosted, bring your own keys.
tel-agent.com · maintained by Dpro GmbH, Vienna
Tel-Agent is an open-source gateway that sits between a phone line and an AI agent.
A call arrives over SIP. Tel-Agent checks the caller against your routing rules and either passes it through to a human, blocks it, or hands it to an AI agent. The agent speaks with the caller in real time, can invoke tools — transfer the call, take a message, check a calendar, call any HTTP endpoint — and every call is recorded, transcribed, and searchable.
It runs on your own hardware, on your own LAN, with your own API keys.
The phone comes first and is the hardest case. After it works, the same agent answers on web chat, SMS, email, WhatsApp, Telegram, Messenger, Instagram and Discord — connected with your own credentials from each platform, never a shared application of ours. Nine channels, and the list is closed. A channel is a route a customer uses to reach you; a system you run your own business on is an integration, and those are reached through webhooks and the HTTP tool.
- Not a PBX replacement. It connects to your existing PBX (3CX, Asterisk, FreePBX) as an extension.
- Not a workflow automation platform. Webhooks and a generic HTTP tool reach n8n and Home Assistant, which do that job better. A channel is where the conversation happens; an integration is a system the agent acts on. We own the first and reach the second through the HTTP tool.
- Not a CRM.
- Not analog-capable. Bridge an analog line with an ATA; Tel-Agent only speaks SIP.
Well-funded closed products already do "AI receptionist for business". What does not exist is a good open, self-hosted one — where you own the recordings, choose the models, and decide which callers ever reach the AI at all.
Pre-alpha. Not usable yet. There is no installable release.
The project is at Milestone 0: getting a single conversation answered end to end in a web chat — the reply streaming token by token, interruptible mid-sentence, with the message captured and the transcript printed. The messaging channels follow, and the phone comes last, at Milestone 11.
The screens exist and have nothing behind them. Twenty-eight of them are in this repository, designed and built; there is no backend serving them yet. Treat them as design, not as a product you can run.
The build order is deliberate, and it was reversed once, on 2026-08-22. It originally
required an answered phone call before anything else was built; the phone loop was
proven elsewhere, which retired the risk that ordering existed to cover. What was not
proven is that anyone can reach the agent at all. The superseded rule and the cost of
reversing it are recorded in internal/DECISIONS.md as D-017.
Milestone 0 of 12 — in progress. The full plan, and what each milestone means, is
in docs/ROADMAP.md.
Watch or star the repository if you want to know when it becomes installable.
| Layer | Choice |
|---|---|
| Voice agent | Python + LiveKit Agents |
| API | Python + FastAPI |
| Frontend | Next.js + React |
| Database | PostgreSQL — transcripts need real full-text search |
| Cache / queue | Redis |
| Reverse proxy | Caddy — automatic HTTPS |
| Packaging | Docker Compose |
Providers for v1: Deepgram (STT) · one cloud LLM · ElevenLabs (TTS). Local models (Ollama, Whisper, Piper) follow in v1.1 — they need a GPU to hold a natural conversation, so they are not the default.
Latency target: under 800 ms from the end of caller speech to the first audio out. Everything streams; the first sentence starts speaking while the rest is still being generated.
Not available yet. Once Milestone 9 lands, this section becomes:
git clone https://github.com/Dpro-at/Tel-Agent.git
cd Tel-Agent
cp .env.example .env # add your API keys
docker compose up -dUntil then, see docs/SPEC.md for the full design and
CLAUDE.md for the development rules.
- API keys for an STT, an LLM, and a TTS provider (or a GPU for local models)
- A machine on the same LAN as the PBX
- Network access to the PBX on 5060/UDP and an open RTP port range
- A SIP endpoint. Most lines already are one:
| Your line | What you need | Extra hardware |
|---|---|---|
| A PBX — 3CX, Asterisk, FreePBX | An extension on it | None |
| A landline from an ISP | These are IP-based now. Either the provider gives you SIP credentials, or your router acts as a SIP registrar and you register against it — common with Fritz!Box in Austria and Germany | None |
| A genuinely analog line — old copper, a fax line | An ATA to bridge it, e.g. a Grandstream HT801 | ~€30 |
Tel-Agent only ever speaks SIP. That is deliberate: supporting telephony hardware directly is a project of its own, and an ATA solves it for about the price of a cable.
- Do not expose the port to the internet. VPN, Tailscale, or a reverse proxy with HTTPS are the supported paths.
- A password is required on first run. There are no default credentials.
- API keys are encrypted at rest and are never returned in full to the client.
- Recording announcements are on by default. Austria requires both parties to be aware that a call is recorded, and the requirement still applies once a human takes over from the agent.
Contributions are welcome, but note the current state: until the agent answers on one
channel end to end, pull requests adding features will be pointed at
IDEAS.md rather than merged. That is not a judgement on the idea — it is how this project stays finishable.
All contributors must sign the CLA before their first pull request is
merged. Read CONTRIBUTING.md before opening one. Everything in the
repository — code, comments, commit messages, documentation — is written in English.
Found a security problem? Do not open a public issue — see
SECURITY.md.
AGPL-3.0. Copyright © Dpro GmbH.
If you run a modified version of Tel-Agent as a network service, you must publish your modifications. The free version is never crippled; it is the product.
For a commercial license permitting closed-source integration, contact Dpro GmbH at info@dpro.at.
Dpro GmbH · Wipplingerstraße 20/18, 1010 Wien, Austria · FN 631492s, Handelsgericht Wien