Claude Sonnet 5 handles date ambiguity in HR benchmark

Puter.js tested Claude Sonnet 5 against Sonnet 4.6 using a prompt to calculate employee bonuses based on tenure. The input contained a trap: hire dates were mixed formats. Riley’s date (25-04-2019) is DD-MM, while Morgan’s (09-30-2022) is MM-DD.

The challenge was Jordan’s date (06-07-2021). If read as June 7, tenure exceeds five years, triggering a 7% bonus. If read as July 6, it falls three days short, resulting in a 4% bonus. Sonnet 4.6 completed the task without flagging the conflict, applying both formats inconsistently to reach a result.

Sonnet 5 identified the format mismatch, presented both potential bonus outcomes for Jordan ($100,580 or $97,760), and asked a clarifying question. According to Artificial Analysis, Sonnet 5 has a higher cost per task than Opus 4.8 before accounting for promotional pricing.