Particle launches Particle-1 token-efficient software engineering model

Particle released Particle-1 on 28 October 2026, a software engineering model post-trained on DeepSeek V4.1 Flash using Cascade RL and GSPO with a rank-64 LoRA adapter. Across DeepSWE 1.1, Terminal-Bench 2.1, ReactBench, and ADE Bench, Particle-1 matches base pass@1 accuracy while reducing output tokens by 28.4% to 52.2% and cutting task cost by up to 51.6%, priced at $0.25 per million input tokens and $1 per million output tokens on the Particle API and OpenRouter.