Setting up fonio as your phone service

fonio is a phone assistant from the German-speaking region and comes all in one: a phone number, the AI voice on the phone and servers in Germany. Connected to Zirko, it creates inquiries and emergencies and follows your rules. What Zirko does in all this, and what never, is explained in Connecting an AI phone service.

Who it is for: businesses in Germany, Austria and Switzerland. fonio's terms do not provide for other countries of establishment; everywhere else, ElevenLabs is the way.

First, in Zirko: under Settings → Company → AI phone service, Connect a phone service is switched on and you have created a key for fonio. Below, under How to set up your phone service, choose fonio — every value is there, ready to copy.

What you need at fonio

According to fonio, the Solo plan costs €119 a month (net) with 1,000 minutes and one phone number; the requests to Zirko during the call are included in every plan.

The number: usually you take the number that comes with fonio and forward your business number to it — with ordinary call forwarding. According to fonio, that is what most people do. Or you connect your phone system through a SIP trunk, an internet line for phone systems; ask your phone provider about it. (Information from fonio, checked on 12 October 2026.)

The steps

Some of fonio's menus are in English — the words below are written the way you see them there.

1. Create four HTTP requests (Assistant → Webhooks → Add HTTP request): Get rules, Recognize caller, Create inquiry and Report emergency, each set to run during the conversation. An HTTP request is a query fonio uses to check with Zirko during the call. Enter the key in the Authorization header — a field that travels along with every request: Bearer, a space, then the key. fonio fills in the caller's number itself.
2. Instructions and greeting: copy the section for the instructions from Zirko. It is in English because language models follow it most reliably — the assistant still speaks the caller's language. The greeting is the sentence from your rules, saying that an AI is speaking and the call is being recorded.
3. Audio recording (Assistant → Technical settings): if Record audio is on, fonio stores every call as an audio file for 30 days. Zirko does not need the audio — leave it off, the transcript remains. If you turn it on, get the caller's consent for it.
4. Have emergencies put through to you (optional): with the Transfer calls action, fonio forwards an emergency to your emergency number. If voicemail picks up there, fonio counts that as put through — so switch voicemail off on that number. fonio cannot put through calls with a withheld number; then there is only the emergency email from Zirko. If you like, fonio sends a summary to an address when putting the call through fails.
5. Test: call your number and ask for the opening hours. If the key in Zirko then shows Last used: just now, the connection works.

Fill in your Rules for calls before the test — without opening hours and an emergency rule, the assistant has nothing to say.

Where the calls are stored

According to fonio, it processes in the EU, with servers in Germany. You sign the data processing agreement with fonio yourself. Zirko only holds the inquiry, see Inquiries from the phone.