Meta Graph API: Development mode can return empty data with no error

Core concept

A Meta app (Instagram/Facebook Graph API) starts in Development mode. In that mode, most endpoints work fine as long as the calling account is added as a tester and has accepted the invite. Comments are the exception: GET /{media-id}/comments returns a valid 200 with data: [], no error at all, until the app is switched to Live mode in the App Dashboard. Everything else, correct scope, accepted tester invite, valid token, can be right and comments will still come back empty.

This isn’t called out anywhere in the comments endpoint’s own docs. It reads exactly like “no comments yet” or “wrong permission”, not “wrong app mode”, so it’s easy to spend time re-checking scopes and tester status instead.

Where to check and fix it

App Dashboard → Settings → Basic has the Development/Live toggle at the top. Switching to Live may prompt for basic info first (privacy policy URL, etc.) depending on the app’s product setup. Once Live, the exact same request against the exact same token starts returning real comment data.

Rule of thumb

An empty data: [] from a Meta Graph API endpoint, with no error, is not confirmation that access is correctly scoped. For comments specifically, confirm the app is in Live mode before trusting an empty result.