How Do You Write a Script and Knowledge Base for an AI Receptionist?

Short answer: an AI receptionist needs four pieces of writing: a one-sentence greeting, short instructions that say who it is and what it may and may not do, hand-over rules for the calls that must reach a person, and a knowledge base built from the questions your callers really ask. Write everything to be heard rather than read: short sentences, one fact at a time, numbers in a form that sounds natural. Then ring it yourself and fix what you hear.

Why is writing for a phone agent different?

On a website, a visitor can scan a paragraph. On the phone, the caller hears one sentence after another and cannot scroll back. Long answers get interrupted, lists of six options get forgotten, and an address read out like a web page sounds strange. The agent writes each reply during the call, but it takes its tone and length from what you write.

1. The greeting

The agent says the greeting word for word, so this is the one line you fully control.

• Name the business first. "Thanks for calling Northside Dental" before anything else, because many callers say "hello" over the first second.
• Decide whether to say it is an assistant. For example: "You're through to our virtual assistant." Some places have rules about this; see do you have to tell callers it's an AI.
• End with an open question. "How can I help?" works better than a list of options.

2. The instructions

Instructions are the agent's job description. Keep them in plain language and in short sections:

1. Who it is. "You answer the phone for Northside Dental, a family dental practice in Leeds."
2. What it does. "Answer questions about services, hours and prices. Book, move or cancel check-ups. Take a message for anything else."
3. What it never does. "Never give clinical advice. Never quote a price that is not in the price list. Never promise a same-day appointment."
4. How it speaks. "Keep answers to one or two sentences. Ask one question at a time. Read phone numbers back in groups."
5. What to collect. "For a message, get the caller's name, number and the reason for the call, and read the number back."
6. What to do when it doesn't know. "If the answer is not in your information, say so and offer to take a message for a callback." This single line prevents most wrong answers.

3. The hand-over rules

Write down which calls must reach a person, in concrete terms: "the caller asks for a person", "the caller says they are in pain", "the caller wants to complain", "anything about a bill over the amount on the price list". For each, say what happens out of hours, for example take a message and schedule a callback for the morning. More on the mechanics in how an AI agent should transfer a call.

4. The knowledge base

The knowledge base is where the facts live, so the instructions can stay short.

• Start from real questions. Ask whoever answers the phone today for the twenty questions they hear most, and make sure each answer exists in writing.
• Use your own pages. Your website, service pages and FAQ are a good base. Check they are current; the agent will repeat an old price as confidently as a new one.
• Put prices and services in a table. One row per service, with the price and duration in the same row, so a price never gets separated from what it is for.
• Write facts the way they are said. "We're open eight till six on weekdays" sounds better than a timetable grid.
• Leave out what callers shouldn't hear. Internal notes, staff names you don't want shared, anything confidential.

A short example

Greeting: "Thanks for calling Northside Dental, you're through to our virtual assistant. How can I help?"

Caller: "How long does a check-up take, and can I come in next week?"

Good reply: "A check-up takes about half an hour, and I can book you in. Do mornings or afternoons suit you better next week?"

Notice the reply answers one thing, moves to the next, and asks a single question. That style comes from the instructions.

How to test before going live

1. Call it with the ten most common questions and check every answer against your knowledge base.
2. Ask something that is not covered and check it admits it and offers a message.
3. Ask for a person and check the hand-over.
4. Interrupt it mid-sentence, speak quietly, call from a noisy room.
5. Read the transcripts, change one thing at a time, and call again.

Doing this in ThinnestAI

The greeting and instructions live in the agent's settings. The knowledge base takes a website crawl, a sitemap, pasted text and uploaded files such as PDFs and CSV price lists, and one knowledge base serves every language the agent speaks. You can tell the agent to answer only from your documents; see answering only from your documents. There is no flow builder to draw: you write rules in plain language and test with real calls. Next step: the AI receptionist page.