Tesora is a Y Combinator S25 startup building frontier AI for actuaries and AI-native software for insurance underwriting and actuarial workflows. Its agents serve P&C carriers, reinsurers, and MGAs by ingesting loss data and automating rater development with audit trails and compliance reviews, eliminating spreadsheet and email bottlenecks. The company forward-deploys into carriers and MGAs to connect disparate systems and encode expert workflows. Tesora is based in San Francisco and was founded in 2025.