How Hindsight Gave My Agent a Real Memory

"It actually remembered." My teammate stared at the screen as CodeMentor AI greeted her with — "Last time you struggled with hash maps. Want to try a problem that builds on that?" We hadn't written a single line of personalization code. That was somewhere around 1:30 AM. I was in Pune, running on chai and stubbornness, and this was probably my third hackathon. I had been building for about 14 hours straight using AI tools to move fast — and honestly, even I didn't fully expect it to work this well. Try it live: codemento.netlify.app How This Started I'll be straight with you — I didn't know what Hindsight was when the hackathon started. The problem statement said "build AI agents that learn using Hindsight" and I opened the docs, got confused, and ended up just asking Claude to explain it to me like I was five. Turns out it's actually simple. Hindsight is a memory layer for AI agents. Three operations: store a memory, fetch relevant memories, reason over them. That's it. Once I underst