Devin Fusion's dual-model setup scores 68 on Coding Agent Index at 31% lower cost than Claude Code
ArtificialAnlys · x · 2026-10-21
Artificial Analysis benchmarked Cognition's Devin Fusion CLI, which runs a frontier lead model alongside a cheaper sidekick model in parallel — the lead handles planning, delegation and final review while both work with their own context and tools.
With Claude Opus 5.5 (max) as lead and GPT-6 Luna (high) as sidekick, it scores 68.1 on the Coding Agent Index, about 2 points above Claude Code with Opus 5.5 (max) at 66.0, and close to Claude Code + Sonnet 5.5 (68.4) and Muse Code (68.0).
- Cost: $9.01 vs $13.04 per task (31% cheaper); 55 vs 65 minutes average
- Per-benchmark: higher on DeepSWE v1.1 (72.6% vs 68.4%) and SWE-Atlas-QnA (69.6% vs 66.4%), slightly lower on Terminal-Bench 4.0 (62.1% vs 63.1%)
- Costs are pay-per-token API prices, not subscriptions
A strong validation of the lead-plus-sidekick architecture for coding agents.
More from coding & agent
- GameForge plugin lets Hermes Agent build playable games and playtest them itself — Teknium · 2026-10-21
- Tired of re-authing every new AI tool? Use a gateway like executor — verrsane · 2026-10-21
- Community builds 4 GUIs for the Pi coding agent as official client stalls — solyarisoftware · 2026-10-21
- Dev uses AI to upgrade Laravel app from 5.8 to 11 in two days — hermanschutte · 2026-10-21
- Nace.AI Launches Drex Max 2.0, a 27B Local Decision Model for Computer Use — DotaMate · 2026-10-21
- 'The purge of tests': theo is Thanos-snapping 50% of his tests away — vincent_koc · 2026-10-21