Hello, the Google calendar check availability tool appears to return no data when called. As such the calendar creates an overlapping appointment. This happens no matter how I prompt the system. I’ve read the discord and documents but no suggestion appears to work (e.g. disconnect integration and reconnect, delete and recreate tool, etc…). The inability to check for conflicting appointments using the vapi.ai built in tools, makes the platform unusable. Please help.

Suggestion: Double-check that your

startDateTime

,

endDateTime

, and

timeZone

fields are provided in strict ISO 8601 format when calling the Google Calendar Check Availability tool. For example:

json
{
  "startDateTime": "2025-09-10T09:00:00Z",
  "endDateTime": "2025-09-10T09:30:00Z",
  "timeZone": "UTC"
}

Incorrect formatting or missing timezone can cause the tool to return no data. If the issue persists after confirming this, please reach out to [Vapi support](support@vapi.ai) with your request details for further assistance. Sources: - [Google Calendar Integration Documentation](https://docs.vapi.ai/tools/google-calendar) - [Vapi Support](https://docs.vapi.ai/support)

I am using the vapi dashboard and not writing json. Where do you suggest I do this?

I can handle this sire accept request let's talk about it

Hey there, When working with the availability tool, a few prompt adjustments often help resolve these issues: - **Filter strictly on “free” status**: When checking the specified date, only treat slots marked as

"free"

as available. Any other status should be considered busy. - **Standardize to UTC**: Convert the specified timezone to UTC and use only the UTC equivalent when searching for available times. This avoids mismatches and ensures accuracy. Please add these guardrails to your current tool/assistant prompts and let us know if it improves the results.

Hey there, I’m having an issue with my google_calendar_check_availability_tool. The calendar is successfully connected, and the tool returns responses when checking availability. However, even when certain slots are already booked in my Google Calendar (for example, 2 PM and 4 PM on October 13th), the assistant still says those times are available and even books new bookings in those already-occupied slots. The events are created directly in the same calendar that’s connected. Could you help me figure out why the tool isn’t recognizing busy slots correctly, even though the integration appears to be working? Thanks in advance 🙏

Please make sure the guardrails that were provided earlier are in the assistant or tool prompts