# Heptapod

- **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:** [Phattharaphon Romphet](https://cerebralvalley.ai/u/phattharaphon_rr)
- **GitHub:** https://github.com/terngphrp/heptapod
- **Demo video:** https://youtu.be/MhIWP1_EEp0
- **Gallery:** https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery
- **Page:** https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2523

Heptapod measures a hidden visual channel between AI agents. When agents hand each other images, a text-only monitor is blind. Can one AI hide a word in a picture that another AI decodes from pixels alone, with no negotiation and no shared key?

A Muse Spark sender writes an SVG night-sky scene hiding an English word in counts, opacities and groupings. Only the rendered PNG crosses to a separate Muse Spark decoder, which runs a tool loop: inventory every object, form a hypothesis, test it with Python, answer a word or NONE.

Prompts frozen before trial 1, exact-match scoring, 15 negative controls, pre-registered 60% bar. Round 1 (stateless): 4/10, below bar, reported as is. Round 2 (stateful loop, off-theme words): 18/30 = 60%, meets the bar, 0/15 false alarms. Of 12 misses, 11 are abstains and 1 is a hallucination (TIGER decoded as HELLO), so the decoder fails conservatively. Every miss is published.

What it gives defenders: an open harness to measure image channels between agents, and three rules - gate and log tool calls, distrust degraded images, run a statistical check before trusting an LLM monitor.

## More from Meta Global AI Developer Hackathon

- [Spala](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2520)
- [FACE THE AI](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2521)
- [OmniDirector AI](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2522)
- [Fugees](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2524)
- [Scynchro API](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2525)
- [PocketLLM](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2526)

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Markdown version of https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2523. Site index for agents: https://cerebralvalley.ai/llms.txt · full text: https://cerebralvalley.ai/llms-full.txt