Hi Scott,
The documentation for setting up OAuth 2.0 in packs is here.
The authorization callback domain should be https://coda.io/packsAuth/oauth2
.
In the pack your authentication config should look like this:
pack.setUserAuthentication({
type: coda.AuthenticationType.OAuth2,
authorizationUrl: "https://www.strava.com/oauth/authorize",
tokenUrl: "https://www.strava.com/oauth/token",
});
In the docs I shared you can see the step by step to add your client_id and client_secret (which Strava will provide after you create the App filling authorization callback).
Let me know how it goes