AgentPay Radar

The problem: x402 (Coinbase's HTTP-402 agent-payment protocol) is live on Arbitrum, but Arbitrum has no discovery surface of its own — projects are findable only through Coinbase's Bazaar, which is (1) generic across all chains, not Arbitrum-curated; (2) polluted with schema-less stubs and one-wallet "factory" listings; and (3) blind to Robinhood Chain entirely, because the CDP facilitator doesn't support it.
An agent that wants the best real, affordable tool on the Arbitrum stack has nowhere good to look.

What we built A buyer-side discovery + settlement layer, built on AgentPay's live x402 gateway:
1. Curated discovery (gateway/radar.py, GET /discovery/arbitrum) — queries Bazaar, filters to the Arbitrum stack (eip155:42161 / 421614 / 46630), drops schema-less stubs and factory wallets, ranks by real usage (unique_payers×3 + calls + recency). Exposed to agents as JSON and to humans as a leaderboard (GET /radar).
2. Robinhood Chain reach — RadarSplit is deployed live on Robinhood Chain (eip155:46630), which Bazaar/CDP cannot index at all, so a facilitator-only directory can't reach it. The discovery-side crawl of Robinhood .well-known/x402 manifests is the next increment.
3. On-chain settlement at 0% fee (contracts/RadarSplit.sol) — an atomic, non-custodial split contract: the agent's USDC moves straight to the listed project (and an optional, default-0 gateway fee), in one transaction. The "visibility → real revenue" hook: listed projects don't just appear, they get paid.
4. Gateway verification (gateway/radar_settle.py) — confirms the on-chain Settled event (contract, payer, developer, amount) before releasing tool data.
5. Agent demo (tools/radar_demo.py) — need + budget → discover → recommend → emit the exact settle plan, end to end.

These are AgentPay's core primitives, not just Radar features: a budget-aware session (a hard spend cap with a running ledger across calls), quality filtering that keeps spend off junk (the stub/factory filter today; cost-aware routing next), and a verifiable receipt for every call. They're free to start — 17 tools, no wallet, no setup — because frictionless onboarding is the wedge. AgentPay monetizes the spending it enables, not the decision to spend: the gateway fee is a contract parameter (RadarSplit.feeBps) we deliberately set to 0% for the Arbitrum/Robinhood promo and that earns on normal routes. The Radar points these primitives at a chain ecosystem that had no discovery of its own.