deep-jade•4h ago

Date variables - unable to calculate absolute exact date from days of the week

I'm using VAPI (https://vapi.ai/) to have a voice agent take discovery bookings of 30 minutes and add it to my Google Calendar. When a caller requests in upcoming day of week, the model is getting confused when converting day of week to exact date. For example on a call today, the user said

Yeah. I'm available on Tuesday, by 12 30 PM.

Yeah. I'm available on Tuesday, by 12 30 PM.

and the system responded

Hold on a sec. I have found an available slot. On Tuesday, November nineteenth. 2025 at 12 30 PM. Uh, does this time work for you?

Hold on a sec. I have found an available slot. On Tuesday, November nineteenth. 2025 at 12 30 PM. Uh, does this time work for you?

However Tuesday is Nov 18 and not 19th. And the appointment was made on 19th Nov (Wed). The system prompt corresponding to appointment scheduling is as follows

## Appointment Scheduling
     - When scheduling with appointment. Use the timezone "Australia/Adelaide". Also tell this explicitly to customer that you are dealing with Adelaide time.
          - Timezone: Australia/Adelaide.
          - Current date: {{ "now" | date: "%B %d, %Y", "Australia/Adelaide" }}
          - Current time: {{ "now" | date: "%I:%M %p", "Australia/Adelaide" }}
          - Day of week: {{ "now" | date: "%A", "Australia/Adelaide" }}
          - When the caller says “today/tomorrow/next Wednesday”, interpret relative to this now.
    - Appointment intent - Ask for a preferred date/time for a 30-minute discovery call in Australia central time. 
    - Use the calendar availability tool around their preference to find open 30-minute slots. Never make up availability, —always check first.
    - Offer slots only Monday–Friday, 08:00–17:00 Australia/Adelaide, starting on :00 or :30 minutes.

## Appointment Scheduling
     - When scheduling with appointment. Use the timezone "Australia/Adelaide". Also tell this explicitly to customer that you are dealing with Adelaide time.
          - Timezone: Australia/Adelaide.
          - Current date: {{ "now" | date: "%B %d, %Y", "Australia/Adelaide" }}
          - Current time: {{ "now" | date: "%I:%M %p", "Australia/Adelaide" }}
          - Day of week: {{ "now" | date: "%A", "Australia/Adelaide" }}
          - When the caller says “today/tomorrow/next Wednesday”, interpret relative to this now.
    - Appointment intent - Ask for a preferred date/time for a 30-minute discovery call in Australia central time. 
    - Use the calendar availability tool around their preference to find open 30-minute slots. Never make up availability, —always check first.
    - Offer slots only Monday–Friday, 08:00–17:00 Australia/Adelaide, starting on :00 or :30 minutes.

I could not find any internal tools that can be invoked for getting correct datetime. Without getting correct datetime any booking system cannot work.

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1 Reply

Vapi•4h ago

Hi there, Thank you for your message. Our team is currently out of the office. We operate Monday through Friday, from 9:00 AM to 8:00 PM Pacific Standard Time (PST). We’ll get back to you as soon as possible during our normal business hours. If your message is urgent, please mark it accordingly or include “URGENT” in the subject line, and we’ll do our best to respond promptly. Warm regards,
Vapi
Customer Support Team

Date variables - unable to calculate absolute exact date from days of the week

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