How can I evaluate the soft skills of engineers without turning interviews into therapy sessions?

Answer:

Soft skills are best tested through concrete scenarios, not abstract questions. Ask candidates to walk you through a recent conflict or disagreement and how they handled it, or how they explained a hard technical trade off to a non technical stakeholder. Pay attention to whether they take some responsibility, or only blame others. Pair programming on a small task can also reveal a lot: do they narrate their thinking, ask clarifying questions, and invite your input, or do they go silent and defensive. Add a short written exercise such as a design note or a user facing explanation of a feature; clear writing is a strong signal of clear thinking.