Analysis reveals Claude Sonnet 5 has higher effective costs and lower quality than predecessor despite lower per-token pricing
Feature update Provisional 65% confidence first seen
Coverage examines how Anthropic's Claude Sonnet 5, despite offering 33% lower per-token pricing than Claude Opus, actually costs 3.7x more on common agent tasks due to consuming 10-12x more tokens. Testing shows Sonnet 5 produces lower quality output on architecture tasks (78% vs 90% idiomatic evaluation) while being more expensive in practice, highlighting how per-token pricing alone is an unreliable metric for model selection across different tokenizers and use cases.