Pi Labs

Pi Labs developed tools to help AI application teams define and measure output quality. Its Pi Studio generated evaluation rubrics from product requirements, system prompts, or descriptions of an application. Teams could upload outputs as CSV or JSON, or paste them directly, then apply a rubric to test prompts, compare model versions, and validate applications before deployment.

Founded by David Karam and Achint Srivastava, Pi Labs focused on applying research breakthroughs to the application layer. Pi Studio used preference pairs and user feedback to calibrate evaluation criteria, translating relative judgments into application-specific metrics. As teams collected more examples and feedback, its agent refined those metrics. Evaluations could run through the studio or integrations with Arize AI, Braintrust, and Promptfoo.

Pi Labs was acquired within Microsoft in 2025, with Microsoft’s acquisition history identifying the transaction as a LinkedIn acquisition. The founders and their team joined Microsoft, marking the company’s transition from an independent AI evaluation startup.