Send personalized prep emails for new Calendly bookings (SendGrid)

Build me an agent workflow that sends a personalized prep email to every new Calendly invitee, the moment they book.

Trigger: a Calendly webhook subscription on the invitee.created event for my organization. Every time a new booking comes in, fire the workflow with the webhook payload.

When the workflow fires, do the following:

1. From the webhook payload, grab the scheduled event URI and the invitee URI. Use Calendly's Get Scheduled Event to pull the event start time, end time, event type name, location/conferencing details, and the host. Use Calendly's List Event Invitees (or Get Event Invitee) to pull the invitee's name, email, timezone, and their answers to any custom booking questions.

2. Hand all of that to the agent and ask it to write a short, warm prep email to the attendee. Rules for the email:

- Under 150 words total, plain text, no marketing styling, no emojis, no images. It should read like a one-to-one note from a real person.

- Open by confirming the meeting time, formatted in the attendee's own timezone (from the Calendly invitee record), with the day of week.

- Restate the meeting topic using the attendee's own words from their booking question answers. Quote or paraphrase what they actually wrote, do not invent goals they did not mention.

- Include a one-line agenda derived from those same answers (for example: "I'll walk through X, you tell me about Y, and we'll figure out next steps on Z").

- End with one specific prep question for them to think about before the call, tailored to what they said they wanted to discuss.

- Sign off as me (use my name and a one-line signature, which I'll provide in config).

- If the attendee did not answer any custom questions, fall back to a short prep email keyed off just the event type name and time, without inventing details.

3. Send the email with SendGrid's Send Email operation. From: my verified sender address. To: the invitee's email. Subject: something like "Prep for our {event_type} on {day, time tz}". Body: the plain-text email the agent wrote. Reply-to: my address.

Other requirements:

- Only send for the invitee.created event. Ignore invitee.canceled.

- Skip sending if the booking is less than 30 minutes away (the prep email won't help) and just log it.

- Skip internal teammates: if the invitee email matches my company domain, do not send.

- Make the sender name, sender email, my display name for the sign-off, and the company-domain skip list easy to configure at the top of the workflow so I can tweak them without editing logic.

Additional information

What does this prompt do?

Watches Calendly for new bookings and reacts within seconds of an invite being scheduled.
Writes a short, warm prep email that confirms the meeting time in the attendee's own timezone and restates the topic using their own words from the booking form.
Adds a one-line agenda and one specific prep question, so the attendee shows up on time and ready to talk.
Sends the email through SendGrid from your own sending domain so it lands in the inbox, not a marketing folder.

What do I need to use this?

A Calendly account where prospects or customers book meetings with you
A SendGrid account with a verified sender or domain you can send from
A short signature or sender name you want the email to come from

How can I customize it?

Change the tone or length of the email, for example more formal for enterprise calls or more playful for community ones.
Send different prep emails for different Calendly event types, like a discovery call vs. a customer onboarding call.
Adjust what goes into the agenda and prep question, for example pulling in product interest, company size, or any other booking question.

Frequently asked questions

When does the prep email get sent?

Within a few seconds of the booking. Calendly notifies the workflow the moment an invite is created, the agent drafts the email, and SendGrid sends it right away.

Will it use the answers the attendee gave on the booking form?

Yes. The agent reads the attendee's own answers to your Calendly booking questions and works them into the topic line, agenda, and prep question so the email sounds like it was written for them.

Can I have different emails for different meeting types?

Yes. You can tell the agent to use a different angle for each Calendly event type, for example a discovery call vs. a paid customer kickoff vs. a partner intro.

Will the email show the correct time in the attendee's timezone?

Yes. The agent uses the timezone the attendee chose at booking, so the time in the email matches what they saw on Calendly.

Can I keep this personal and not turn it into a marketing blast?

That is the point. The email is capped at around 150 words, written one-to-one, and sent from your domain, so it reads like a quick note from a real person.