Direct evidence
A live HTTP 402 response with decodable payment requirements is the strongest endpoint signal. The index records status code, protocol version, scheme, network, asset, amount and payee when available.
Discovery with evidence.
x402mpp.sh is an independent index. It does not define the x402 standard and it does not treat any single marketplace or analytics provider as canonical.
Catalog evidence
Bazaar resources can enter the graph before a direct probe succeeds. They remain attributed to the source catalog and become stronger records when direct evidence appears.
Self-sovereign discovery
Known hosts are checked for common well-known x402 manifests and sitemap hints. Manifest resources are queued for direct verification.
Ecosystem evidence
Directories, facilitator registries, foundation material and community indexes are treated as discovery seeds. They are not silently converted into transaction claims.
Payment metrics
Metric snapshots keep source identity. Official ecosystem totals and third-party measured subsets are displayed separately because collection scope can differ materially.
Indexability
Every normalized record receives a stable server-rendered HTML page. Sitemaps, RSS, JSON Feed, robots, llms.txt and machine datasets are rewritten after each publishing cycle.