Worked on the promptfoo/promptfoo repository to enhance the reliability and security of multi-provider evaluation workflows. Focused on preventing the leakage of max_tokens through passthrough configurations, the work involved implementing request-body sanitation to strip max_tokens when not applicable, particularly for GPT-5 and other reasoning models. Updated configuration handling ensured consistent behavior and reduced the risk of data exposure across providers. Automated tests were added to validate safe request handling and configuration paths, supporting robust and scalable evaluation flows. The engineering approach emphasized API development, thorough testing, and TypeScript, resulting in improved configuration hygiene and workflow stability.