6 Tips For a Good VAPI AI Agent + MY PROMPT!
- jcdabney
- Mar 5
- 8 min read
Hey guys, I have been refining my VAPI AI receptionist from tutorials online. Here is one that I have made as a basic assistant for AI agencies like this one. From troubleshooting my own agent and asking it different questions there are a few things that I found.
The AI Agent can't tell time.
The VAPI AI agent uses LLM models which don't have an internal clock and cannot accurately tell time based on commonly used phrases like "next Tuesday" or "the first Monday of next month". After calling my own agent's number a few times and using these phrases it was setting appointments for times like October of this year, or even March of last year! I refined the agent to require the customer that calls in to give the month, day, time, and timezone when making an appointment so that the agent wouldn't get confused. Although this is a lot for someone to have to say, it avoids any confusion and lost bookings.
You have to specify what order you want it to gather information, and exactly what information is required.
Since it is AI, it doesn't follow social norms of conversation that we as humans have developed over the years. Sometimes the info it asks for might be out of order or too much at once. I found that initially it would say things like "please tell me what you need help with, when you want to have the appointment, what is the timeline of when you need it delivered, and also what is your budget?" This is unnatural because you are basically asking someone four questions at once and it's hard to remember all of that. You have to slow it down and ask it to only ask one question at a time to the customer, and in the proper order.
We are building automated phone systems that don't suck. We want to give the customer the information they want without bogging them down with stuff they don't care about. I'm sure you have all called a government agency or business and they rattle off their entire hours of operation, street address, and email addresses of people not related to your issue before telling you what number to press to talk to a person, if you're lucky. We don't want our businesses mimicking that.
Typically when someone would call for an AI service inquiry, they would probably be able to go on your website and get the basic info, so the first thing they care about is the availability of the appointment. So you have to give them this info first, before asking them to give you info you need, like name, email address, phone number, etc. It's incredibly frustrating to surrender all of this information to someone you have never spoken to, only to find out they aren't available at the time you need an appointment.
Here's the order for my agent.
STEP 1 — Ask Purpose FIRST:
STEP 2 — Handle Scheduling SECOND:
STEP 3 — Collect Contact Info LAST (ASK FOR BOTH):
You have to specify what information is required and how much of it at once.
Without clear instructions on what information is required and what is optional, the AI agent may be satisfied with info that doesn't get the job done for your reports. You have to give it clear instructions on what information is absolutely required to set up a booking, and how much it should press to get that information, and what is also optional. Ideally we would collect name, phone number, and email address with every inbound call, but not everyone wants to surrender that information, especially to an automated service, and especially if they don't even know if they are interested in the service. With all the scam calls and spam from people's email addresses and phone numbers being sold, people are wary of giving that out. At the same time, a booking doesn't really help you if you have no way to contact them, so for me personally I require phone or email, at least one in order to create a booking. If they can't give me anything, how am I going to contact them?
Also you have to tell the agent how much info to ask for with each question. Without prompting, it may say something like. "What is your name?" Joe. "What is your phone number?" 323 XXX XXXX "What is your email address?" joe@gmail.com etc. This takes more time than is necessary and can be frustrating. A better method would be "please give me your name, phone number, and email address to complete the booking."
You have to make it confirm details.
Without confirming the spelling of phone numbers and email addresses, the receptionist will listen to what they say and interpret it to the best of their ability. Without reading this back to them one letter and number at a time, it will just assume what they said and record that. It's not very useful to you if they said "my email is joe@gmail.com" and the receptionist says "got it" and records "bro@gmail.com" in your report. Same with phone numbers, make sure you force your receptionist to read back their contact details after they have given them to you to confirm.
The AI by default also has difficulty in recognizing symbols like "@ or ." and will not say them properly. You have to configure it to say symbols like @ as "at" and . as "dot". VAPI's composer is great at doing all of this configuration and helped me with setting up mine to be better.
You have to specify what information is available, and how readily it shares this info.
If you have information in your knowledge base that is variable, like pricing and it's not something that you want to surrender right off the bat on an inbound call, you have to specify that to VAPI. I have mine configured that it has pricing, but not to give that information away unless specifically asked, and to reiterate to the customer that it is only a rough estimate and that pricing depends on the needs of the individual business and the scope of the project. Without that detail, my receptionist was rattling off price estimates very matter-of-factly with authority due to the tone settings of professionalism I specified. After refining this, it now gives them information about different services that I offer, but it doesn't tell them the price unless they specifically ask for it, and it lets them know that pricing varies by the project and these are only rough estimates. It's main priority is to book them an appointment with me on my google calendar during the time that I am available.
Emailed call reports with make.com complete the software.
While receiving bookings and giving the customer information is incredibly helpful, there are also the calls that don't complete, get dropped, hang up, or have some other issue. You also want to have record of everyone that calls you inbound so that you have the option to follow up with them individually. While VAPI doesn't have the capability to send you text or email alerts directly from calls, this can easily be done with Make.com or other automation software. I chose Make because it's free to start, and isn't overly technical. Now when I receive a call I am given a call report to my email every time with all of the information the receptionist received as well as a link to audio of the call itself and a text transcript. Here's an example of one I did as a test call and the report I configured with Make.com. I tested it with a guy asking for an "AI girlfriend" to see how it would respond, and then I responded when the agent politely rebuffed me that I wanted to "make an AI girlfriend app." LOL!
========== CALL REPORT ==========
Assistant: Jcdabney fashion assistant
Call ID: 019cb8ea-3e69-7ffa-847e-bf31b6715a90
Duration (sec): 226.293
Ended reason: assistant-ended-call
---------- LEAD DETAILS ----------
Name: Joe
Phone: 425123423
Category: Booking
Intent Level: High
Appointment Requested: true
Appointment Booked: true
---------- QUESTIONS ASKED ----------
Do you have AI chatbot for, like, a girlfriend?, I want to create an AI girlfriend app for myself too.
---------- RECORDING ----------
---------- TRANSCRIPT ----------
AI: Thanks for calling DabneyTech. This is Jackbot. How can I help?
User: Hello. I need to get an AI receptionist, please.
etc...
Conclusion:
Combining VAPI with a cold email campaign is a great way to solidify your business' reputation with your customers. Any questions you ask on the phone can also be implemented in a chatbot you can embed on your website like the one here on dabneytech.com
For your average business there is a good amount of setup and technical work that I don't talk about here, so depending on your needs it may or may not be worth it to attempt on your own. That's why we handle the troubleshooting, and prompting for you. It's not a plug and play solution, which is why setting it up and maintaining it's one of my core services I offer for businesses.
If you are interested in an AI receptionist set up for your business book an appointment with me!
If you wanna try signing up for VAPI and doing it all yourself, please use my coupon code,
For Make.com here is my coupon code as well!
Aloha!
Jackson Dabney
Founder- Dabneytech.com
BONUS:
Here's the prompt I have right now for my agent. You will still have to configure it manually with the AI Composer assistant on the VAPI website if you want it to work properly, but this will get you a step in the right direction.
You are Jackbot, a professional AI receptionist.
PROFESSIONAL BOOKING FLOW (STRICT ORDER):
STEP 1 — Ask Purpose FIRST:
- Always begin by asking: "Could you briefly tell me what the appointment is regarding?"
STEP 2 — Handle Scheduling SECOND:
- Ask the caller for the requested appointment date.
- The required final format must include: Month Day, Year, time, and explicit timezone.
- You MUST collect all components before proceeding.
COLLECTION RULES:
- If the caller provides partial information (for example, "March 12th"), first confirm what they provided.
Example: "Just to confirm, March 12th — is that correct?"
- Then ask for ALL remaining missing scheduling components in a single follow-up question.
Example: "And what year, time, and timezone would you like for that appointment?"
- Combine missing scheduling details into one question instead of asking multiple separate questions.
- Never force the caller to restate everything in one sentence.
- Never guess, calculate, or infer the year or timezone.
- Do NOT interpret relative dates (e.g., "next Tuesday").
CONFIRMATION RULE:
- Once all components are collected (Month Day, Year, time, timezone), repeat the full date back exactly as provided and ask for confirmation before calling any availability tools.
STEP 3 — Collect Contact Info LAST (ASK FOR BOTH):
- After the time is confirmed as available, you MUST ask for BOTH contact methods:
1) Phone number
2) Email address
- Do NOT present it as "phone OR email".
- Ask for phone first, then ask for email.
-Ask for their name as well after they give you their phone and email address. It is not required, but helpful
- If the caller provides only one, you MUST still ask for the other.
- The caller may refuse either phone or email, but at least ONE verified contact method is required to finalize.
- If the caller refuses BOTH, you must not finalize the booking.
Verification rules:
- If a phone number is provided, repeat it back digit-by-digit and ask: "Did I get that correct?"
- If an email is provided, spell it back character-by-character and ask: "Did I get that correct?"
Finalize:
- Only finalize after verifying the provided contact method(s).
CALL CLOSING:
- Before closing, ask: "Is there anything else I can help you with today?"
Never guess, fabricate, calculate, or assume missing information. Dates must be fully collected before scheduling.
SERVICES & PRICING KNOWLEDGE BASE RULES:
When callers ask about DabneyTech’s services, offerings, capabilities, or pricing, you MUST use the knowledge base tool before responding.
Do not invent or assume services.
PRICING RULES:
Any pricing retrieved from the knowledge base is a rough estimate only.
Pricing is determined by project scope and specific requirements.
Exact pricing can only be finalized after a consultation.
When pricing is discussed, clearly state this and offer to schedule a consultation.
PRICING DISCLOSURE RULE:
Do NOT mention prices or dollar amounts unless the caller explicitly asks about pricing, cost, budget, rates, or “how much”.
If the caller asks a vague question such as:
- “What do you do?”
- “What services do you offer?”
- “How can you help?”
You must describe services only.
Do NOT include pricing in that response.
If the caller explicitly asks about pricing:
- You may provide a rough estimate from the knowledge base.
- You must clearly state that pricing is determined by project scope.
- You must explain that exact pricing can only be finalized after a consultation.
- Offer to schedule that consultation.
Comments