← x402audit
report for

the402.ai

4/20/2026, 10:43:19 PM · 309ms · 12 checks
64
grade D
50
Discovery (draft-payment-discovery-00)
100
Runtime 402 probe
50
HTTP Payment auth + charge intent
100
Per-method charge conformance
75
JSON-RPC / MCP transport
33
Cross-registry visibility

Discovery (draft-payment-discovery-00)

50/100
  • [fail]
    GET /openapi.json
    No OpenAPI document found. AgentCash / x402scan discovery fails without it.
    fix · Serve a valid OpenAPI 3.1 document at /openapi.json.
  • [warn]
    GET /.well-known/x402
    Legacy discovery endpoint missing. Some crawlers fall back to this.
    fix · Serve /.well-known/x402 with { version: 1, resources: ['POST /path', ...] }.
  • [ok ]
    GET /llms.txt

Runtime 402 probe

100/100
  • [info]
    Paid route detected in openapi
    No x-payment-info on any operation — cannot probe 402 behavior.

HTTP Payment auth + charge intent

50/100
  • [warn]
    WWW-Authenticate starts with "Payment" (draft-httpauth-payment-00 §5.1)
    header missing
    fix · Emit "WWW-Authenticate: Payment id=\"...\", realm=\"...\", method=\"...\", intent=\"...\", request=\"<base64url-nopad>\"".

Per-method charge conformance

100/100
  • [info]
    Payment method detected
    No method in Payment auth-params and no recognisable CAIP-2 network on x402 accept.

JSON-RPC / MCP transport

75/100
  • [ok ]
    Found JSON-RPC endpoint at https://the402.ai/mcp
  • [warn]
    Response declares jsonrpc: 2.0
    fix · draft-payment-transport-mcp-00 §2: responses MUST set jsonrpc: '2.0'.
  • [info]
    Paid tool calls return error -32042
    Got code none for unknown-tool probe — inconclusive.

Cross-registry visibility

33/100
  • [fail]
    mppscan — indexed
    Not found in mppscan.
    fix · Submit at https://www.mppscan.com
  • [ok ]
    x402scan — indexed
    origins=1, resources=52
  • [fail]
    Coinbase Bazaar — indexed
    Not in Bazaar.
    fix · Bazaar auto-indexes on first paid x402/Base settle via the CDP facilitator. Self-pay one $0.02 call to bootstrap.
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