x402 Counterparty Score

Decision-grade counterparty scores for the x402 ecosystem, sold to AI agents over MCP (Model Context Protocol) with per-call x402 payments (USDC). Input an x402 endpoint URL or pay-to address; output is a trust verdict (trusted/caution/avoid) with wash-trading ratio, real-buyer count, and repeat-buyer rate. Every response carries provenance: source, updated_at, confidence.

This page exists for humans verifying the service before funding an agent wallet. Agents consume the service directly over MCP; the machine-readable descriptions below are the exact tool contract.

Tools

Tool	Price	Description (verbatim tool contract)
`score_x402_counterparty`	$0.02/call	Returns trust verdict (trusted/caution/avoid) with wash-trading ratio, real-buyer count, and repeat-buyer rate for an x402 endpoint URL or pay-to address. $0.02/call. Updated daily from Base on-chain settlement data and the x402 Bazaar catalog.
`get_sample_score`	Free	Returns a clearly-marked stale sample counterparty score in the exact response schema of score_x402_counterparty (verdict, wash_trading_ratio, real_buyer_count, repeat_buyer_rate, source, updated_at, confidence). Free, no payment required, no input required. Sample data is fixed and expired by design — use it to validate response parsing, then call score_x402_counterparty ($0.02/call) for fresh decision-grade scores.

Endpoint and payment

MCP endpoint: send JSON-RPC 2.0 messages via POST /mcp on this origin (MCP Streamable HTTP). GET /mcp returns 405: the optional SSE notification stream is not offered.

Payment is per call via the x402 protocol in USDC. A call to the paid tool without payment returns an in-band quote; the quote is authoritative for price, asset, network, and pay-to address. Error responses settle no payment: stale or missing answers are never sold (answers older than 24 hours are withheld, not served).

Data sources

x402 Bazaar catalog — the official public discovery layer, read without a key.
Public on-chain settlement transfers, read via the CDP SQL API.
Daily 402 handshake probes of catalogued endpoints — availability and declared price/schema, over the public x402 protocol.

Open, publicly licensed sources only; no commercial API data is resold. Per-source licensing basis is documented on the methodology page.

Verify this service

Methodology — deterministic scoring rules, verdict thresholds, confidence definition, coverage limits, probing and bootstrap-settlement disclosures.
OpenAPI specification — endpoint and tool input/output schemas, x402 payment flow, error envelopes.
llms.txt — the same facts, plain text.
Call get_sample_score over MCP — free, returns the exact response schema with a clearly-marked stale sample.