What happened: URL in calendar was not filled in (to give return link to Agenda note) rather the return link was put in Calhdar “notes” field
What I expected: the callback URL to be put in calendar URL field not notes!
Putting in notes fields means link is not “live” in fantastical (while it is in Apple Calendar) manual copy/paste to URL field gives solution that works for both Fantastical and Apple Calendar - why not just put it in the RIGHT field when Agenda sets up the Calendar record?
Things that might be helpful to know (Agenda version, OS and model, etc):
We moved things into the Notes field because the URL field is often used by itself and inserting the agenda URL would erase whatever url you already had (as only one such field is supported). Best is to ask the makers of Fantastical to support tappable links in the Notes section (as they anyway should given that for instance Google Hangout and other meetup like services insert conference call urls etc in there too.
I regularly loose the agenda link, because I receive updates to invitations with updated meeting information etc. which replaces the notes-field.
I am using some shortcuts to sync two different iOS calendars and want to preserve the agenda link… none of my entries so far did use the URL field but all of them have content within the notes field.
Having agenda append the agenda-link makes things more complex when syncing.