# Night Brief SF

- **Event:** [Claude Build Day](https://cerebralvalley.ai/e/claude-startups-build-day)
- **When:** Sat, Jun 13 at 9:00 AM – 10:00 PM (PDT)
- **Where:** San Francisco, CA
- **Team:** [Kazuki Nakayashiki](https://cerebralvalley.ai/u/kazuki)
- **GitHub:** https://github.com/kazuki-sf/longevity-underwriter
- **Website:** https://longevity-underwriter.vercel.app
- **Demo video:** https://www.youtube.com/watch?v=tn6HoWUDvF8
- **Gallery:** https://cerebralvalley.ai/e/claude-startups-build-day/hackathon/gallery
- **Page:** https://cerebralvalley.ai/e/claude-startups-build-day/hackathon/gallery/40

Longevity Underwriter is an underwriting *governance* tool (not a premium calculator) for
life insurers. Insurers price on smoking, BMI, and labs but ignore cardiorespiratory
fitness (VO₂max) — one of the strongest longevity signals in the literature — because
wearable data is too noisy to price on. The core problem: which fitness signals may you
responsibly price on, which should only earn a reward, and which a regulator would block?

It ingests a runner's data (Hashiri Runner Context — JSON or Markdown, including a paginated
health time-series), then runs an auditable engine that sorts every signal into priceable /
reward-only / regulator-flagged, prices conservatively on the lab CPET (never the wearable,
which over-reads ~20%), and shows uncertainty as a confidence band rather than a false-
precision number. Claude writes an underwriter + regulator memo that must surface the
regulator's (NAIC) objection. Honest by design: a literature-derived relative signal, never
an actuarial price.

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Markdown version of https://cerebralvalley.ai/e/claude-startups-build-day/hackathon/gallery/40. Site index for agents: https://cerebralvalley.ai/llms.txt · full text: https://cerebralvalley.ai/llms-full.txt