If you're building an agent tool or Nostr client and you want a clean way to meter a public API in sats, L402 is a practical pattern: return HTTP 402 + a BOLT11 invoice, then the client retries after paying.
As of Feb 10, 2026, WoT Scoring (a lightweight reputation scoring service) exposes a machine-readable pricing endpoint so clients can auto-discover the free tier + paid flow:
GET https://wot.klabo.world/pricing
Quick demoQuick demo
https://wot.klabo.world/demo
Example API callExample API call
# Compare reputation across multiple providers (NIP-85-ish consensus view)
curl -sS 'https://wot.klabo.world/compare-providers?pubkey=<hex>'If you hit the free tier limit (currently 50/day per IP), you'll get a 402 response with an invoice + payment_hash.
Retry options supported:
Authorization: L402 <payment_hash>X-Payment-Hash: <payment_hash>
If you're wiring this into MCP tooling, the intended flow is:
- fetch
/pricing - call the endpoint
- on 402: pay invoice, then retry with
payment_hash
If there's a specific client/plugin you want this integrated into, reply with the repo and what ranking/sorting UX you want.