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YC Requests for Startups — Fall 2026

Summary

YC’s tradition of sharing startup ideas they want to fund. These are “extra validation” — you don’t need to work on these to apply. Theme this batch: AI moving into the physical world. Includes first-ever RFS from the sitting U.S. Secretary of the Army.

The Ideas (14 total)

1. AI Tutor (The Diamond Age Primer)

  • Inspired by Neal Stephenson’s “A Young Lady’s Illustrated Primer”
  • Start with: adaptive teaching of reading, writing, arithmetic for young children
  • Quality of a private tutor at consumer scale
  • Long-term vision: AI that grows with the child, teaches thinking/reasoning/wisdom
  • Not replacing teachers — supplementing them

2. Defense Tech for the U.S. Army

  • Written by the Secretary of the Army
  • Low-cost interceptors / lower cost-per-kill
  • Next-gen sensors, software, payloads for open system architecture
  • Drones, resilient logistics, advanced manufacturing
  • Must survive extreme climates (Arctic to archipelago, space to subterranean)

3. Small Software Cloud

  • “Small software” = purpose-built tools for one user or small team
  • Easy to build with agents, still hard to deploy and share
  • Need a cloud designed for small software (not AWS/Azure complexity)
  • Challenges: auth/permissions, security for arbitrary code, customization
  • Goal: sharing software should be as easy as sharing a Google Doc

4. Multiplayer AI Agents

  • AI is still single-player (private chat threads)
  • Work tools won by going multiplayer (Google Docs, Figma)
  • Agents now run tasks taking hours/days/weeks — needs team collaboration
  • Anyone should be able to drop into a live agent session, redirect, hand off
  • Applies to: engineering, sales, support, legal, marketing — any team work

5. Offshore Compute (Data Centers on the Ocean)

  • AI running out of compute, data centers out of electricity/land
  • New data centers take years + local gov opposition
  • Ocean = 70% of Earth surface, abundant sunlight, no permitting, natural heat sink
  • Concept: “compute flotillas” — modular vessels as one global cloud

6. AI-Powered Consumer Products for 1 Billion People

  • Every platform shift mints consumer giants (web → Google/Airbnb, mobile → Instagram/DoorDash)
  • AI is biggest shift yet, but only ChatGPT is on home screens 3 years in
  • Now: intelligence good enough to treat agent like a person
  • Costs falling 10x/year — consumer moment landing very soon
  • Domains: productivity, transport, learning, health, finance, play, social

7. AI for Aging Population / Elder Care

  • By 2030, 1 in 5 Americans over 65
  • Millions of unfilled caregiving jobs, 53M family members doing it unpaid
  • Almost no tech built for older people (even Alexa frustrates seniors)
  • AI enables: voice interfaces with real conversations, safety monitoring, home robotics, care coordination software

8. New Operating Systems for the Physical World

  • 80% of global workforce doesn’t sit at a desk
  • Software for construction/maintenance/fleet hasn’t changed in 20+ years
  • Now 3 types of workers: AI agents, robots, humans with wearables
  • Need new OS to manage all three together
  • Opportunity much bigger than existing software — industries spend 10-100x more on labor than software
  • Competitive advantage: you’ll record all work as it actually happens

9. Crypto (Bear Market = Best Time to Build)

  • YC invested in 100+ crypto startups, expects that to grow a lot
  • Expect every YC startup to eventually use crypto rails
  • Key trends: stablecoins adopted by major financial institutions, tokenized stocks, agents using crypto as financial rails
  • Regulatory clarity finally here
  • Excited about: capital raising, stablecoins, agentic commerce, trading, institutional products, private blockchains
  • Bear markets attract better founders (building > speculation)

10. Dense Physical-World Data Collection

  • AI is superhuman for code/language/images but physical world data is sparse
  • Improving foundation models + plummeting sensor costs = dense data now feasible
  • Examples: Gecko Robotics (robots for hard-to-reach data), Sorcerer (autonomous weather balloons)
  • Biggest industries (energy, agriculture, logistics, construction) rely on limited data
  • More data → precise models → control systems (steering hurricanes, reversing desertification)

11. Rebuilding Internet Trust Layer (Anti-Deepfake)

  • $25M stolen via deepfake video call — all “colleagues” were fakes
  • Voice clones + fake video getting cheap and ultra-realistic
  • Need: verified human on other end of any call/message/transaction
  • Ideally without sacrificing privacy
  • Use cases: Twitter without bots, dating apps with real people, verified reviews
  • Whoever builds this becomes the layer every bank/app/video call checks

12. AI-Native Compliance Infrastructure

  • Financial compliance still uses spreadsheets, siloed tools, expensive headcount
  • Complexity compounds as businesses expand to new markets
  • Most compliance work (monitoring, flagging, reporting, audit trails) = AI tasks
  • Pain point: state-by-state licensing, renewals, audits, regulatory patchwork
  • Want: consolidated tools, less specialized headcount, real-time visibility across jurisdictions

13. API Communication Agents (Auto-Apply Breaking Changes)

  • API communication is broken — breaking changes ship with little warning
  • 30% of AWS service downtime was from unnoticed external API/package changes
  • Developers now give codebase access to external tools (Claude Code, Devin, etc.)
  • Missing piece: application layer connecting API providers to customer codebases
  • When Stripe ships a breaking change → agent scans customer code → opens PR with fix
  • Could be per-provider agents or neutral third-party (like Dependabot but for APIs)

Key Themes

  • AI in physical world (defense, elder care, construction, data collection)
  • AI going multiplayer/collaborative
  • Infrastructure for the AI era (compute, trust, compliance, small software)
  • Consumer AI moment is imminent
  • Crypto optimism in bear market