Tech Ocean

Oct 7, 2026 · Artificial Intelligence

Claude Code Model & Effort Pairing: Real-World Test Across 5 Tasks, 4 Models, 5 Effort Levels

The author benchmarks four Claude Code models (Haiku 4.5, Sonnet 5.5, Opus 5.5, Fable 5.1) across five effort tiers on five typical coding tasks, revealing that Sonnet, Opus, and Fable succeed at low effort while higher tiers only add verification and cost; Haiku misses boundaries that Sonnet low catches; Fable at low effort modifies out-of-scope code; switching effort preserves cache but switching models forces full recomputation.