The comparison of AI-driven bug detection tools OpenAI's o4-mini and Anthropic's Sonnet 3.5 highlights their performance in detecting complex bugs across multiple programming languages, including Python, TypeScript, Go, Rust, and Ruby. The evaluation dataset consists of sixteen domains with self-contained programs in each language, introducing a range of realistic and difficult-to-catch bugs to assess the models' capabilities. Anthropic Sonnet 3.5 outperforms OpenAI o4-mini overall and demonstrates superiority in detecting subtle concurrency errors in Go and logical reasoning capabilities in strongly-typed languages like TypeScript and Ruby. The analysis suggests that Sonnet's reasoning-based architecture is particularly valuable in detecting nuanced bugs, while o4-mini excels in environments with abundant training data, such as Python.