AI Combinator lets founders stress-test their Y Combinator application by running it through a panel of five simulated YC partner personas simultaneously. Each persona reviews your application independently, fires sharp follow-up questions in a mock interview format, then the panel delivers a PASS/FAIL/MAYBE verdict with green flags, red flags, one brutal honest takeaway, and specific fixes to strengthen your submission. The whole session takes minutes and produces a shareable card for X. Useful for catching weak spots in your narrative, tightening your answers to the hard questions, and building confidence before the actual interview. Not affiliated with Y Combinator.