# Caliper

- **Event:** [Meta Global AI Developer Hackathon](https://cerebralvalley.ai/e/meta-ai-developer-hackathon)
- **When:** Oct 26, 12:00 PM – Nov 4, 9:00 PM (EST)
- **Where:** Online
- **Team:** [Eka Vardhan](https://cerebralvalley.ai/u/Eka)
- **GitHub:** https://github.com/eka1357/caliper
- **Demo video:** https://www.youtube.com/watch?v=EG3yOoDF60k
- **Gallery:** https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery
- **Page:** https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/1656

Caliper measures size and speed in phone video, or refuses when the video can't support a number. Muse Spark 1.3 turns the question into a measurement plan and audits the evidence; SAM 3.1 tracks the object and the reference; deterministic Python computes the value and a 90% range. The model never writes the number.

Evaluated honestly: on the QuantiPhy holdout our pre-registered claim failed on the official score (20.1 vs 58.1), because refusals count as misses. But when Caliper answers, 9 of 15 answers land within 10%, against 4 of 15 for Muse Spark alone, and its range held on 13 of 15. On our own scooter, it measured 5 of 6 passes against GPS with a 7% median error. Also usable by other AI agents through an MCP server.
"""
Live: https://caliper-sigma.vercel.app
"""

Built during the hackathon (Oct 27 to Nov 4); planning docs and field clips are listed separately in the README.

## More from Meta Global AI Developer Hackathon

- [Whybox](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/1653)
- [CaseBrief](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/1654)
- [MNL Tech Solution](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/1655)
- [Harsh](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/1657)
- [ZabSoft](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/1658)
- [VisorQA](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/1659)

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Markdown version of https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/1656. Site index for agents: https://cerebralvalley.ai/llms.txt · full text: https://cerebralvalley.ai/llms-full.txt