Parameters for evaluating candidates in the UPSC interview include clarity of thought, communication skills, and overall personality traits. Interviewers assess the candidate's analytical abilities through their responses to situational and behavioral questions, as well as their understanding of current affairs and social issues. Furthermore, candidates' ethical perspective and decision-making processes are scrutinized to gauge their suitability for civil service roles. The panel also looks for attributes such as confidence, adaptability, and teamwork skills, which are crucial for effective public administration. Overall, a holistic evaluation determines a candidate’s potential as a future civil servant.