Cursor has launched its self-developed Agentic programming model, Composer 2.5.

Elon Musk invited users on the X platform to test the latest version of Cursor, Composer 2.5, which is partially trained using Colossus 2. Cursor officials stated that the model is based on Kimi K2.5, focusing on improving stability for long tasks and the ability to follow complex instructions. Technically, it employs text-based targeted reinforcement learning, with the synthetic training scale increased to 25 times that of its predecessor, and uses sliced Muon and dual-grid HSDP to optimize training efficiency.