Cursor's Composer 2, marketed as frontier-level coding intelligence, was revealed to be fine-tuned from Kimi K2.5, an open-source model by Chinese AI startup Moonshot AI backed by Alibaba.

AI coding startup Cursor released Composer 2, a software-development-only model trained exclusively on code data, scoring 61.3 on CursorBench and matching Claude Opus 4.6 and GPT-5.4 at significantly lower token prices, as the company enters talks for a $50 billion valuation.