Vals AI: teams of SI agents cost 1.8–5.1 times more than single agents but barely improve results
Prepared by Sintelligent with the help of SI. Published in SI: . Updated: .
Many SI agents instead of one cost noticeably more for hardly better results — sometimes it is cheaper to just turn up the reasoning.
Vals AI ran GPT-6 Sol and Claude Opus 5.5 on Vibe Code Bench, alone and as teams, at medium and maximum reasoning effort. Teams cost 1.8–5.1 times more; only one of the four comparisons showed a statistically significant improvement — GPT-6 Sol at medium effort, up 7.3 points. According to Vals AI, raising a single agent from medium to maximum effort added 11.4 points, while adding a team on top of it added only 1.4, not statistically significant. As The Decoder reports, Anthropic's own data on Opus 5.5 shows the same: going from 10 to 100 agents raises quality only slightly (from 0.70 to 0.74 in one test). Vals AI concludes that whether a team pays off depends on the model, the task and the budget.
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