AI Startups Ideas by YC, Summer 25

What Top VC’s Look For

2025 is shaping up to be the year of AI-native startups.

And Y Combinator just dropped another confirmation of it: their latest Requests for Startups (RFS) — a list of startup ideas they want to fund.

This isn’t trend-chasing. These are invitations. If you’re building with AI (or thinking about it), this is your signal.

So in today’s post, we’re diving into what YC’s RFS says about where startups are headed:

– What is “full-stack AI,” and why is it important
– Why YC wants more designers, scientists & teachers to become founders
– The rise of AI agents, internal bots, and voice assistants
– Sectors begging for reinvention: healthcare, security, education, finance
– And some wild startup ideas hiding between the lines

Let’s unpack it all — fast, clear, and idea-packed.

The “Full-Stack AI” Mindset

Most founders build AI tools and try to sell them to slow-moving incumbents. YC’s take? Don’t sell to the dinosaurs — make them extinct.

“You could build an AI agent and sell it to law firms... Or, you could start your own law firm, staff it with AI agents, and compete with the existing law firms. That, my friends, is going full-stack.”
— Jared Friedman, YC

This is the kind of reframing that hits hard. Don’t build for the system — rebuild the system. A school run by AI tutors. A clinic run by AI agents. A logistics company with zero manual coordination.

And it’s already happening.

🏛️ Garfield AI

Garfield AI is a fully AI-powered law firm in the UK.
It helps clients send debt recovery letters for £2 and file lawsuits for £50 — no lawyers involved, just an AI interface guiding users through the entire legal process.
Even more impressive? Garfield received official approval from the UK’s legal services regulator (SRA) — a huge signal that AI-native institutions are not only possible, but already here.

YC calls it full-stack AI. It’s not just software — it’s owning the whole vertical, rebuilt with intelligence baked in.

New Roles, New Founders

If full-stack AI is about rethinking industries, the next question is: who should build them?

YC has a clear answer: designers, teachers, scientists — this is your moment.