One of Silicon Valley’s most storied startup accelerators, Y Combinator, held its Winter 2025 Demo Day on Wednesday, showcasing what its latest batch of 160 startups are cooking up. Some of Silicon Valley’s most successful startups — including Stripe, Airbnb, and Reddit — started out in a YC batch. Today, YC’s newer startups are focused on building the next big thing in AI. In this batch, we noticed a surprising number of startups creating tools to enhance other companies’ AI agents. Rather than...