Composer 2.5 release and technical analysis

Composer 2.5 发布与技术解析

Cursor released Composer 2.5, built on a Moonshot open-source checkpoint, trained with synthetic data from real codebases at 25 times the previous scale, and updated with text-feedback reinforcement learning and a sharded Muon optimizer.

Why it matters: HKR-H/K/R all pass: Cursor is a core coding-agent surface, and the post gives concrete training details around Moonshot, 25x data, RL, and Muon. It lacks benchmarks, pricing, or user-facing capability limits, so it stays in the 78–84 band.