Setup guide

Setting up Fonio: seven steps to your first agent.

This guide takes you from registration to the first real call. Budget about 30 minutes for a usable first version. No technical background needed — but use a computer, not a phone.

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In short: Create an account → create an agent → set voice and greeting → write the prompt → add your most common questions → enable actions such as email summaries and calendar booking → assign a number and test. The prompt is the part you will spend longest on and the part that makes the biggest difference — there is a template for it below.

What to have ready before you start

The three to five questions that come up most often on your phone — with the answers you normally give.
Your opening hours and what should happen outside them.
A phone number the agent forwards to when in doubt.
A decision: does the agent get a new number, or do you forward your existing one?

Create the account and secure the discount

The account first — the discount cannot be added retroactively.

Register through the partner link. The discount is pre-applied at checkout.
If no discount shows at checkout, an ad blocker is the most common cause. Then enter the code from our email manually.
Choose the plan by call volume. Rule of thumb: up to roughly 20 calls a day Solo, above that Team. If calls need to be answered simultaneously, Team is the minimum — Solo handles one call after another.

The 30-day money-back guarantee starts at purchase. It pays to actually use the agent in the first days rather than only configure it — otherwise the window closes before you know whether it carries.

Create the agent

An agent is a configuration: voice, behaviour, knowledge and actions in one place.

Go to "Assistenten" in the left menu and click "Assistent erstellen".
Choose the type "Telefon-Assistent" (phone agent).
Give it an internal name that describes its job — "reception day shift" or "order line weekend". The name is only visible to you, but by the third agent you will be grateful for it.

Prefer several narrow agents over one that does everything. A reception agent and an order-line agent can be improved separately, without touching a 40-line prompt every time.

Voice, language and greeting

The first impression happens in the first five seconds — and you control all of them.

Pick a voice: since version 3.5 there are over 70, and you can preview each one. Take the two minutes and listen to three or four instead of taking the first.
Set the language to the one most of your callers speak. Callers in other languages are still detected and the agent switches.
Write the greeting. The formula: salutation + who is speaking + an invitation to talk.

Three greetings that work

Medical practice: "Good morning, you have reached Dr Meier's practice. I am the practice's digital assistant and I will take your request. What is it about?"
Trades: "Good afternoon, this is the digital assistant of Kramer Electrical. I can take appointment requests and answer questions. How can I help?"
Law firm: "Good morning, Schuster & Partner. You are speaking to the firm's digital assistant. I will take your request and pass it on. How can I help?"

Important: the greeting must make clear that an AI is speaking — from August 2026 the EU AI Act requires it. And if you want to record calls, the greeting has to say so at the start and obtain consent (§ 201 German Criminal Code, GDPR).

The prompt — the agent's brain

This decides whether the agent is good or embarrassing. Four blocks are enough: who you are, what the goal is, how the conversation runs, where the limits are.

About you: the agent's name, its role, the company, what you offer.
Goal of the conversation: what should have happened by the end? Appointment booked, request captured, question answered, call transferred.
Conversation flow: the steps in the order you would follow them on the phone yourself.
Limits: what the agent does not talk about and what it does instead. The most important block — without it the AI will invent something when in doubt.

Prompt template to adapt

# About you
You are [name], the digital phone agent of [company] in [city].
[Company] offers [services in one sentence].
You speak in a friendly, concise way and in full sentences.
No filler, no sales language.

# Goal of the conversation
Capture the caller's request completely and make sure it reaches
the right place. If an appointment is wanted, book it. If you are
unsure about something, say so and take a callback request.

# Conversation flow
1. Greet and ask what it is about.
2. Summarise the request and have it confirmed
   ("Did I understand correctly: …?").
3. If it is a question from the knowledge base: answer it.
4. If an appointment is wanted: offer free slots and book.
5. Ask for name and callback number, read the number back
   digit by digit and have it confirmed.
6. Summarise what happens next and say goodbye.

# Limits
- Never quote prices that are not explicitly stored.
- Make no commitments about dates, delivery times or outcomes.
- Give no information about [sensitive topic in your industry].
- For complaints, emergencies, or if the caller explicitly asks
  for a human: transfer immediately to [phone number].
- If you do not know something, say: "I cannot tell you that
  reliably — I will note it and a colleague will get back to you."

Write the prompt the way you would brief a new temp who is smart but does not know your company. Everything you would have to tell that person belongs in it. Nothing else does.

Add the most common questions

The prompt governs behaviour, the knowledge base governs content. Mixing the two makes the prompt unreadable.

Enable "Wissensdatenbank" (knowledge base).
Add the three to five most common questions with answers — phrased exactly as you would say them on the phone.
Optionally add more sources: company information as text, or PDFs.
After a few days, look at the inbox of unanswered questions. What shows up there are the gaps — and filling them helps more than any further prompt polishing.

Keep answers short. On the phone a 40-word sentence is unreasonable, no matter how good the voice is.

Actions: what happens after the call

An agent that answers calls but passes nothing on has only moved the problem.

Enable the email summary and use an address that is actually read. This is the single most important setting.
Optionally SMS notifications — useful when someone in the field needs to react quickly.
Since version 3.5, summaries can also be sent via WhatsApp.
Connect appointment booking: Fonio's own scheduler, Calendly or Cal.com.
Define the transfer target: a user, a phone number, or via SIP to your existing system.

Check the summary email against one real conversation. If it does not contain what you need to call back, a step is missing in the prompt — usually asking for the callback number.

Assign a number and go live

The final step, and the only one where something can go wrong that real callers notice.

Either assign a new number under "Nummer zuweisen", or forward from your existing number.
For forwarding: conditional (only when busy or after X seconds) is the gentler start, unconditional (always) the decisive one.
Before going live, use the in-browser "Testanruf" — repeatedly, and with the cases that could go wrong.
Then make a real call through the forward. The browser test checks the agent, not the telephony.

Start with a conditional forward: the agent only steps in when nobody picks up. That way you collect real conversations without your main channel being affected by the first mistake. Switch to unconditional once the summaries look clean.

Afterwards

The first week decides

Read the conversations

Read the first ten to twenty summaries in full. Do not skim — that is where you see which parts of the prompt are too vague.

One change per round

Adjust the prompt, test, read again. Change five things at once and you will not know which one helped.

Sharpen the limits

Almost every awkward answer can be stopped with one more sentence in the "Limits" block. It is the change with the best effort-to-effect ratio.

Two ways to your 10 %

Start straight through our partner link — the discount is pre-applied at checkout. Or have the code and the guide sent to you by email and decide in your own time.

Start with Fonio → Hear the demo first

30-day money-back guarantee · An active ad blocker sometimes prevents the discount from being attributed — in that case take the code by email.

Request the code by email

You will receive your personal :percent % code plus the setup guide in one email. The code is deliberately not shown on this page.

No spam, no sharing with third parties. We send a confirmation email first — the code only goes out after you click it.

FAQ

Questions about setup

Do I need technical knowledge?

No. Setup runs entirely through forms, nothing is programmed. The only part that takes some practice is the prompt — and there is a template for it above.

How long does it really take?

A first working agent: about 30 minutes. An agent you are genuinely happy with: more like two or three rounds over one to two weeks, because only real conversations show you where it gets things wrong.

Can I set this up on a phone?

Technically yes, practically no. Writing the prompt and filling the knowledge base is typing work — do it at a computer.

What if the agent says something wrong?

Then a limit is usually missing from the prompt. Add a sentence covering exactly that case ("You make no commitments about delivery times, you take a callback request instead") and test again. This is why a conditional forward is the safer start.

Can I run several agents on different numbers?

Yes, and it is usually the better solution than one do-everything agent. How many numbers you can run in parallel depends on the plan.

Can I get this guide by email?

Yes. When you request the discount code we include the short version — with the prompt template ready to copy.