Personalized AI welcome video for new Calendly bookings

Build me an agent workflow that emails every newly booked Calendly invitee a short, personalized AI welcome video so they walk into the meeting already feeling like they know the rep.

Trigger: a Calendly webhook on the invitee.created event. The workflow should run the moment a booking lands.

When the webhook fires, call the Calendly Get Event Invitee operation to fetch the invitee's name, email address, the event's scheduled start time, the invitee's timezone, and every question and answer pair from the booking form (the questions_and_answers field).

Then check how far away the meeting is. If the scheduled start time is more than two hours from now, take the personalized path. If it is less than two hours away, take the fast fallback path described below.

Personalized path: draft a 20 to 30 second spoken script that (1) greets the invitee by their first name, (2) references the meeting time formatted in the invitee's local timezone in a natural way (e.g. 'Tuesday at 2pm your time'), and (3) acknowledges at least one specific answer from the booking-form questions, such as the goal they typed in or the company they listed. Keep the tone warm, conversational, and brief. End with one short sentence about what to expect on the call.

Call HeyGen's Generate Avatar Video operation with the script, the configured avatar_id, and voice_id. Then poll HeyGen's Retrieve Video Status operation every 8 to 10 seconds until status is 'completed' or 'failed'. Cap the wait at 5 minutes. Once completed, call HeyGen's Retrieve Shareable Video URL operation to get a public share link.

Fast fallback path (meeting is less than two hours away, or the personalized render failed or timed out): call HeyGen's Generate Video from Template operation using a pre-configured fallback template_id with the invitee's first name filled in as a template variable. Poll Retrieve Video Status the same way and then fetch the Retrieve Shareable Video URL.

Finally, send the email via Gmail's Send a Message operation to the invitee. The subject should reference the upcoming meeting (e.g. 'A quick hello before our chat'). The HTML body should include a one-line warm intro, the share link rendered as a clickable thumbnail or button labeled 'Watch your welcome video', and a sign-off from the rep. Send from the configured Gmail account.

Configuration the workflow should expose: the HeyGen avatar_id, the HeyGen voice_id, the HeyGen fallback template_id, the fallback cutoff in hours (default 2), the polling timeout in seconds (default 300), the sender name, and the email subject template.

Error handling: if the Calendly event has been canceled or rescheduled between the webhook firing and the invitee lookup, skip silently. If HeyGen returns a 403 (plan limit) or a failed render, fall back to the template path. If Gmail send fails, log the error with the invitee email and video link so the rep can resend manually.

Additional information

What does this prompt do?

Listens for new Calendly bookings the moment they happen and pulls the invitee's name, scheduled time, and the answers they typed into your booking form.
Writes a short, friendly script that greets them by name, calls out their meeting time in their local format, and references something they shared (like the goal they typed in).
Generates a 20 to 30 second AI avatar video in HeyGen with your branded avatar and voice, then emails the share link from Gmail before the meeting.
If the booking is less than two hours away and a fresh render is unlikely to finish in time, falls back to a pre-built HeyGen template video so the invitee still gets a personal touch before the call.

What do I need to use this?

A Calendly account with permission to create webhooks on your event types.
A HeyGen account on a paid plan (Creator or higher) with at least one avatar and voice you want to appear on camera.
A Gmail account to send the welcome email from.
Optional: a pre-built HeyGen template video to use as the fast fallback for last-minute bookings.

How can I customize it?

Tweak the script style and length, from formal and concise to warm and casual, or change the call-to-action at the end of the video.
Choose which booking-form answer the script references, like the goal they typed in, the company size they picked, or the role they selected.
Adjust the cutoff for the fallback template, like switching from two hours to one hour or four hours depending on how fast HeyGen renders for your plan.
Customize the email subject and body copy, including the video thumbnail, calendar reminder link, and any meeting prep you want to attach.

Frequently asked questions

How long does it take to generate the video after someone books?

HeyGen typically renders a 20 to 30 second avatar video in 30 to 180 seconds. The workflow polls until it is ready and sends the email as soon as the share link is available.

What happens if the meeting is starting very soon?

If the booking is less than two hours out, the workflow skips the fresh render and uses a pre-built HeyGen template video instead, so the invitee still gets a personal welcome before the call.

Do I need to record a new avatar for this?

No. You can use any avatar already available in your HeyGen account, including stock avatars or a custom avatar you have trained from your own footage.

Will it work if my booking form has no extra questions?

Yes. If the invitee did not answer any custom questions, the script falls back to a warm greeting that uses only their name and the meeting time.

Can I send the video from a shared inbox instead of my personal Gmail?

Yes. Connect the Gmail account you want the welcome email to come from, whether that is your personal address, a shared sales alias, or a dedicated outreach inbox.