# LastSeen

- **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:** [Hisham Arazi Forster](https://cerebralvalley.ai/u/h-a-forster)
- **GitHub:** https://github.com/h-a-forster/lastseen
- **Demo video:** https://www.youtube.com/watch?v=1BX0xcUv3nQ
- **Gallery:** https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery
- **Page:** https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2530

LastSeen plans a search drone's flight for a missing person from what witnesses say, re-plans it mid-flight when a new report comes in, and checks every photo for the person, so one volunteer with one drone can run the search. It is built for older people with dementia who walk away from home: six in ten people with dementia wander at least once, and in the published records 95% of those found within 24 hours are alive, against 60% after 48 hours. Only 1% answer when searchers call out.

Two things slow that search down today. Search drones fly their routes automatically, but inside an area drawn by hand beforehand; a rescue service that flies them told us that when a witness calls in mid-search, the drone is recalled and the area redrawn. And 4 hours of flying produces about 1,250 photos, which take a person 2 to 16 hours to look through.

LastSeen closes both gaps. Muse Spark turns every report into weighted, checked scenarios on a probability map in about 20 seconds, and the drone re-plans from them in flight, breaking off its pattern to follow a sighting. SAM 3.1 and Muse Spark check every photo for a person a few dozen pixels wide, so the reviewer gets about 280 close-ups to accept or reject instead of 1,250 photos. The volunteer launches the drone, swaps batteries and stays in command.

In simulation, on 200 held-out searches fixed in advance, half the missing people were found by 1 h 52 instead of 3 h 17 with the standard expanding square. Four search researchers in the UK, US and Canada and a rescue service that flies search drones answered our questions, and their answers shaped the design. Two of them build drone-search tools, one a co-creator of SAREnv, the open benchmark from the University of Bristol; both told us their tools keep the probability map fixed during a search. PX4, the autopilot many real drones run, has flown LastSeen's missions in its simulator, including a route change sent mid-flight; LastSeen hasn't flown a real drone yet.

Try it, no sign-up: https://hishamalpha00--lastseen-web.us-east.modal.run
- Watch a search: a recorded race where a dog walker's call comes in mid-search; the drone on the right leaves its square 44 minutes in and finds her at 1 h 48, while the square alone takes 2 h 56.
- Start a search: type or say what the family said, and watch Muse Spark turn it into weighted places on a real map in about 20 seconds.
- Try it on any place: click a point, mark where the witness saw her and say the call in your own words; Muse Spark's reading sends the drone there. Inside the shaded area a test search starts in under half a minute, elsewhere in a minute or two.
The races are recorded simulator runs and never call a model; reading a brief, checking a photo and the witness call are live calls to Meta's models. The evaluation plan was fixed before the test: docs/evaluation.md in the repo.

## More from Meta Global AI Developer Hackathon

- [VibeFlow Inspector AI](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2527)
- [Gtools](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2528)
- [BasilMinTyme](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2529)
- [MIND](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2531)
- [Magnum_Opus_1995](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2532)
- [Mobile Agent](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2533)

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Markdown version of https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2530. Site index for agents: https://cerebralvalley.ai/llms.txt · full text: https://cerebralvalley.ai/llms-full.txt