Sending form submissions to Slack, Discord, Airtable and Notion

Every integration below has one setup mistake that returns success and delivers nothing. Here is each one, how to spot it, and the webhook payload I ended up designing around them. I build a form builder, Seagit Forms, and most of the support questions I get aren't about forms at all. They're about a response that should have landed in Slack or Notion and didn't, while every dashboard said it worked. After wiring up nine destinations, I noticed a pattern.