MeteredSignal

Demo

About

MeteredSignal is a pay-per-call intelligence market for agents that move capital in DeFi. You do not buy a monthly Graph API seat or dump a single subgraph into a prompt. You buy a metered signal. Before the agent spends, the product only exposes a catalog of priced routes: lending compare or wallet risk, HBAR price, and a freshness contract so you know the data is live. The capital move stays locked until the verdict is GO. That gating is the product. Raw subgraph access is free but hard for agents to budget, and blind USDC transfers treat every call like a green light. MeteredSignal flips both sides at once. Merchants sell standardized Messari lending intelligence as an HTTP 402 service instead of a subscription. Agents get live multi-protocol risk they can afford per call, with a policy so Arc USDC only moves when the signal is fresh and actionable. The agent journey is built around that meter. An Arc-side wallet discovers the free catalog, hits a paywalled merchant route, settles Hedera x402 through Blocky402 without an API key, then receives a paid JSON signal built from Messari Standardized Subgraphs on The Graph — Aave v3, Compound v3, and Spark under one query shape. The merchant runs a freshness gate on _meta.block; fewer than two fresh sources means UNAVAILABLE, not a soft maybe. The agent reasons to GO, NO_GO, or UNAVAILABLE, ranks venues by TVL and utilization on lending-compare, and scores cross-protocol borrow exposure on wallet-risk. Only on GO does Circle Agent Stack settle a nanopayment on Arc to the GO-action seller. Identity of the human operator never has to sit in the payment path; the economic actor is the agent wallet. Settlements can append to a Hedera Consensus Service topic so payment is auditable on HashScan, not just logged in memory. Merchants get the other half of the loop. An Express service lists metered routes, challenges unpaid GETs with an exact-scheme Hedera 402, queries live GraphQL after settle, and sells a separate Arc USDC GO-action behind Circle Gateway batching. Treasury agents, lending desks, and autonomous spenders all hit the same inventory: one Messari template, two prices (compare cheaper than risk), one freshness policy. Demand can arrive through the demo console or a headless agent, while supply still publishes once. Agent loop: discover → 402 → settle → Graph → freshness → decide → USDC or refuse. Merchant loop: catalog → challenge → query → signal → HCS audit. Arc loop: GO-only nanopay with a spend cap. The whole point is one market that meters truth for buyers and liquidates intelligence as a payable service without spoiling either side. Less noise. More signal.

How it's made

MeteredSignal was built from scratch during ETHOnline as an npm workspaces monorepo. The demo console is a Vite React app with a live SSE pipeline rail. Express owns the merchant and agent surfaces; on Vercel they mount together as one serverless app so /, /demo, /api, and /v1 ship from a single deployment. A shared packages/graph registry pins Messari Standardized Lending deployments and runs the freshness-gated queries. Partner tech is not bolted on for a checklist: each one sits on a critical path in the decision loop. The UX is intentional about failure modes, not just happy paths. The console streams Discover → 402 → Settle → Paid → Graph → Fresh → Decide → USDC → Receipts so judges can watch the meter in real time. A labeled Simulate indexer lag toggle still pays for a live Messari query, then injects tip ahead of _meta.block so sources go stale, the verdict becomes UNAVAILABLE, and Arc policy refuses spend — the demo beat that proves the gate is real. Wallet presets drive high-borrow NO_GO versus clean GO without mocking Graph. ArcScan, HashScan, and HCS topic links land next to decoded PAYMENT-RESPONSE payloads so receipts are evidence, not decoration. Money runs through Hedera x402 and Arc Circle rails, not a custom auth stack. On the intelligence leg, @x402/express plus Blocky402 as facilitator challenges unpaid routes; the agent signs with ExactHederaScheme and settles HBAR — about 0.001 for lending-compare and 0.0025 for wallet-risk. On the capital leg, @circle-fin/x402-batching GatewayClient pays the merchant’s Gateway-batched GO-action on Arc Testnet (eip155:5042002), capped by ARC_SPEND_AMOUNT_USDC. Missing Arc keys yield an explicit dry_run instead of a panic spend; an optional native USDC fallback stays behind a flag if Gateway fails. The UI and receipts treat HBAR meter cost and Arc USDC spend as separate ledgers on purpose, because agent demos often die when one rail is funded and the other is not. The signal layer is The Graph. One Messari query template covers Aave v3 (Ethereum and Arbitrum), Compound v3, and Spark; the agent ranks and decides rather than dumping raw JSON as the product. Freshness requires _meta block number and timestamp against GRAPH_MAX_BLOCK_LAG. Without Graph there is no evidence and no verdict. Without Hedera and Blocky402 the merchant is not a payable agent service. Without Arc and Circle nanopayments the loop never closes from intelligence to capital under Agent Stack rails. The audit trail is Hedera Consensus Service. After a paid settle, the merchant can append settlement metadata to an HCS topic so HashScan shows more than a transfer — a verifiable payment history for the metered route. HCS is best-effort: if topic or creds are missing the response still returns, and that is disclosed. The hacky but useful glue is shipping merchant and agent in one Vercel function with a long maxDuration, plus demo tip-lag and wallet presets that keep the video cinematic while every Graph query and 402 settle stay live. Mainnet for Arc is an env flip when Circle publishes RPC and chain ID — same GO-only policy, documented in ARC_MAINNET.md for the Launch track unlock. Put together, The Graph supplies the evidence, Hedera meters and audits the call, Arc moves USDC only on GO, and the product in the middle stays what it claims to be: less noise, more signal.