Loops House
Date
Sep 25–27, 2026
Duration
48h
Participants
58
Road to Devcon VI
x402: Pay-Per-Call
Decades ago, when travelling fairs (melas) set up in Indian towns, the center of attraction was often a wooden box mounted on a tripod, the Bioscope. Children and elders alike would queue up, drop a small coin, and peer through a brass eyepiece to watch brief scenes of distant cities, grand spectacles, or legendary stories unfolding frame by frame.
In today’s digital era, this exact experience is returning through x402, the activation of the web's dormant HTTP 402 Payment Required standard.
This weekend, builders will step up as digital bioscope operators, crafting native pay-per-request experiences powered by the x402 protocol.
FAQ
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What do I need to submit?
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Final leaderboard
Pay-per-call x402 API that parses Indian Railways delay notices into structured JSON — settles only when the notice is readable, refunds nothing when it isn't. Base Sepolia testnet. PS1 — The Operator's Booth
1 commits1 contributorlast push Sep 27
The Coin Purse: An Agent That Pays but Can't Be DrainedThe Bioscope: Drop a Coin, Watch a Reel, Never Pay TwiceThe Operator's Booth: Meera's Railway Delay API
Pay-per-call railway delay parser that turns messy notices into structured JSON using x402 on Base Sepolia.
3 commits1 contributorlast push Sep 26
The Coin Purse: An Agent That Pays but Can't Be DrainedThe Bioscope: Drop a Coin, Watch a Reel, Never Pay TwiceThe Operator's Booth: Meera's Railway Delay API
Testnet x402 railway delay parsing API: pay only for successful parses
6 commits1 contributorlast push Sep 26
The Coin Purse: An Agent That Pays but Can't Be DrainedThe Bioscope: Drop a Coin, Watch a Reel, Never Pay TwiceThe Operator's Booth: Meera's Railway Delay API
7 commits1 contributorlast push Sep 27
The Bioscope: Drop a Coin, Watch a Reel, Never Pay TwiceThe Operator's Booth: Meera's Railway Delay API
1 commits1 contributorlast push Aug 9
The Coin Purse: An Agent That Pays but Can't Be DrainedThe Operator's Booth: Meera's Railway Delay API
4 commits1 contributorlast push Sep 27
A digital bioscope with x402-powered pay-per-reel access and wallet-based repeat viewing.
1 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 27
3 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 26
2 commits1 contributorlast push Sep 26
x402-powered HTTP API for parsing railway delay notices into structured JSON, with paid single and bulk parsing on Base Sepolia.
2 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
4 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
6 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 25
14 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 27
Pay-per-call x402 API that parses Indian Railways delay notices into structured JSON — settles only when the notice is readable, refunds nothing when it isn't. Base Sepolia testnet. PS1 — The Operator's Booth
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 26
2 commits1 contributorlast push Sep 26
2 commits1 contributorlast push Sep 26
x402-powered HTTP API for parsing railway delay notices into structured JSON, with paid single and bulk parsing on Base Sepolia.
2 commits1 contributorlast push Sep 26
Pay-per-call railway delay parser that turns messy notices into structured JSON using x402 on Base Sepolia.
3 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
Testnet x402 railway delay parsing API: pay only for successful parses
6 commits1 contributorlast push Sep 26
4 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 25
7 commits1 contributorlast push Sep 27
6 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
9 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Aug 9
No submission made for this problem.
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8 commits1 contributorlast push Sep 26
4 commits1 contributorlast push Sep 27
An LLM research agent that spends real testnet USDC through x402 — hard per-call and total spending caps enforced server-side, never by the model. Includes an honest test stall and a rogue stall with 10+ hostile payment tricks, all refused. ps2 — The Coin Purse
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 26
Budget-enforced x402 research agent with a durable spending ledger
5 commits1 contributorlast push Sep 27
8 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 27
3 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 25
A security-first AI agent that can pay for x402 APIs without exceeding hard spending limits.
1 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
3 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 25
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10 commits1 contributorlast push Sep 26
2 commits1 contributorlast push Sep 25
1 commits1 contributorlast push Sep 26
1 commits1 contributorlast push Sep 27
A pay-per-reel digital bioscope powered by x402, with one-time wallet-keyed payments and cryptographically verified access to private frames.
2 commits1 contributorlast push Sep 27
A digital bioscope with x402-powered pay-per-reel access and wallet-based repeat viewing.
1 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 27
2 commits1 contributorlast push Sep 26
The Bioscope: Drop a Coin, Watch a Reel, Never Pay Twice. x402 V2 Paywalled media on Base Sepolia.
14 commits1 contributorlast push Sep 27
Pay once with x402, return with wallet proof, watch your reel again
6 commits1 contributorlast push Sep 27
Pay-per-reel video paywall on x402 with wallet-based Sign-In-With-X — first frame free, one small coin unlocks the rest, and a returning wallet never pays twice for the same reel. Base Sepolia testnet. PS3 — The Bioscope
1 commits1 contributorlast push Sep 27
6 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
9 commits1 contributorlast push Sep 27
1 commits1 contributorlast push Sep 27
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