Cursor's Composer 2 model was revealed to be fine-tuned from Kimi K2.5, a model by Moonshot AI.
- Composer 2 released on March 19 by Cursor; official blog states it stems from 'our first continued pretraining run' and its Bench scores (SWE-bench 61.3; Multilingual 73.7) surpass Claude Opus 4.6 (58.2).
- About 25% of Composer 2’s pretraining comes from K2.5.
- 77% cost reduction when running K2.5 on Workers AI, from higher-cost previous models.
- K2.5 deployed on Cloudflare's global edge platform; NVIDIA demonstrates Kimi at CES/GTC; Chamath Palihapitiya comments on K2.5’s impact on cost and AI scaling.