The KV Cache: The Hidden Engine Behind Every AI Response

Why your Claude or Cursor session suddenly slows to a crawl, and the simple habits that keep it fast. You’re deep in a Cursor session. First few replies stream back almost instantly. Then, twenty messages in, you hit send and the screen just… stares at you. Ten seconds. Fifteen. A spinner. Nothing changed on your end. Same laptop, same wifi, same model. What happened is you tripped the KV cache, and the AI had to relearn your entire codebase from scratch....

June 23, 2026 · 8 min · 1540 words · Navan Tirupathi