IFTTT's webhooks integration apparently has a usage limit, but no documentation anywhere on what that is or what the limit is (I really, really doubt I hit it). It's also very hard to discover that's the actual problem: you have to go to the activity log for the webhooks.

Because even though it's failing on IFTTT's side they *return a fucking 200*. Give me a 429 Too Many Requests; jesus.