specification: x402
specificationVersion: '2'
provider: Blockscout
providerId: blockscout
generated: '2026-09-14'
method: probed
status: published
description: >-
  The Blockscout PRO API at api.blockscout.com is gated with x402: an unauthenticated request
  returns HTTP 402 with a base64 `payment-required` header carrying the payment requirements,
  and the JSON body "Proceed with API key or make a X402 payment to continue". An agent can
  therefore pay per call in USDC on Base without holding an account or an API key.
endpoint_probed: https://api.blockscout.com/api/v2/stats
response:
  status: 402
  header: payment-required
  encoding: base64 JSON
  body_error: Proceed with API key or make a X402 payment to continue
  signature_header_required: PAYMENT-SIGNATURE
requirements:
  x402_version: 2
  scheme: exact
  network: eip155:8453
  network_name: Base mainnet
  asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
  asset_name: USD Coin
  asset_version: '2'
  amount: '2000'
  amount_human: 0.002 USDC
  pay_to: '0xd441D9F4c59CB26253E2F0A7a62ac9cE7823b4b4'
  max_timeout_seconds: 60
  resource: https://api.blockscout.com/api/v2/stats
discovery:
  well_known: none
  note: >-
    https://api.blockscout.com/.well-known/x402 returns 402 like every other path on the host
    rather than serving a discovery document. The payment requirements are only obtainable by
    making a request and reading the `payment-required` header off the 402.
verification:
  probed: '2026-09-14'
  method: curl -D - https://api.blockscout.com/api/v2/stats; payment-required header base64-decoded
scoring_note: >-
  This does NOT light the Kin Score `agentic_commerce` dimension, which grades UCP/ACP
  well-known documents only — score.rb carries no x402 check by design. Recorded here as
  evidence of the payment surface, not as a scoring artifact.