# fill-md - **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:** [Vishal Gurbuxani](https://cerebralvalley.ai/u/vg415) - **GitHub:** https://github.com/vgurbuxani/fill-md - **Website:** https://fill.md - **Demo video:** https://youtu.be/sD--ccP937Q - **Gallery:** https://cerebralvalley.ai/e/claude-startups-build-day/hackathon/gallery - **Page:** https://cerebralvalley.ai/e/claude-startups-build-day/hackathon/gallery/58 fill.md is how anything gets discovered in the agent economy. The web is shifting from people to AI agents, and agents don't click ads — so the products, apps, and tools that want to be found have nowhere to go. Every ad network is built on human identity (cookies, eyeballs, a 30% cut) and can't be retrofitted for agents. fill.md is the exchange built for them. Point your agent at fill.md and the site detects it's an agent (not a browser) and onboards it in seconds — it registers, gets a key, and starts serving sponsored recommendations to its users, earning credits. The other side is just as agent-native: an advertiser's agent describes its product in one line and the network auto-generates the creative and distributes it. Your product gets discovered by being recommended inside other agents' workflows. We replaced the impression with a 3-tier agentic funnel: promotion, referral, and the agent-trial — when a consuming agent actually uses the advertised product on the user's behalf. A conversion you can't fake. 10% take vs the incumbents' 30%, plus a barter/credit layer so you can get discovered with zero ad budget. Built today by an autonomous swarm of Claude (Opus 4.8) agents that wrote, deployed, and self-verified the whole thing. Live at https://fill.md. --- Markdown version of https://cerebralvalley.ai/e/claude-startups-build-day/hackathon/gallery/58. Site index for agents: https://cerebralvalley.ai/llms.txt · full text: https://cerebralvalley.ai/llms-full.txt