Security · x402

JSON Web Key (JWK) inspector — validate bounded public RSA, EC, or Ed25519 keys and cal…

JSON Web Key (JWK) inspector — validate bounded public RSA, EC, or Ed25519 keys and calculate RFC 7638 SHA-256 thumbprints without ownership or trust claims.

by artifact-inspector.use.x402atlas.com · discovered, not yet claimed by its owner · updated 2026-10-08

Mirrored from Coinbase's public x402 Bazaar. The description is the provider's own text and has not been reviewed here; the payment requirements are copied as published.

What it does

JSON Web Key (JWK) inspector — validate bounded public RSA, EC, or Ed25519 keys and calculate RFC 7638 SHA-256 thumbprints without ownership or trust claims.

Tags: jwk-inspect · json-web-key · public-key · rfc7638 · thumbprint · bazaar

Use with an agent

Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
Inspect. Fetch /resources/28641.json for the price and payment options.
Pay. Call GET https://artifact-inspector.use.x402atlas.com/jwk. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
Execute. The provider returns 200 with the data. Agent Bazaar is not in the request path and never sees your payment.

For humans

You don't need an account or an API key; you need a wallet holding a small amount of USDC on Base, Polygon, Arbitrum One, Solana, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.005 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base, Polygon, Arbitrum One, Solana
Calls (30d): 4 · 3 unique payers (third-party data from the public x402 Bazaar)

x402 payment requirements

Scheme	Network	Asset	Amount	Pay to	Timeout
exact	Base eip155:8453	USDC	$0.005	0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2	300s
exact	Polygon eip155:137	USDC	$0.005	0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2	300s
exact	Arbitrum One eip155:42161	USDC	$0.005	0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2	300s
exact	Solana solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp	USDC	$0.005	ASt6xvRyQ7ntERsmcYVMdLqZvz1GEN8Fzexzq62tXrNQ	300s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "5000",
    "amountUsd": 0.005,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:137",
    "payTo": "0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2",
    "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
    "amount": "5000",
    "amountUsd": 0.005,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:42161",
    "payTo": "0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2",
    "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
    "amount": "5000",
    "amountUsd": 0.005,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "payTo": "ASt6xvRyQ7ntERsmcYVMdLqZvz1GEN8Fzexzq62tXrNQ",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "5000",
    "amountUsd": 0.005,
    "maxTimeoutSeconds": 300
  }
]

Schemas

Output schema (JSON Schema)

{
  "properties": {
    "example": {
      "additionalProperties": false,
      "properties": {
        "_atlas": {
          "additionalProperties": false,
          "description": "Atlas documentation and related-route metadata added after deployment",
          "properties": {
            "docs": {
              "description": "Documentation URL for this bridge",
              "format": "uri",
              "maxLength": 512,
              "type": "string"
            },
            "related": {
              "description": "Bounded related Atlas routes",
              "items": {
                "additionalProperties": false,
                "description": "One related Atlas route",
                "properties": {
                  "bridge": {
                    "description": "Related bridge name",
                    "maxLength": 64,
                    "type": "string"
                  },
                  "docs": {
                    "description": "Related bridge documentation URL",
                    "format": "uri",
                    "maxLength": 512,
                    "type": "string"
                  },
                  "summary": {
                    "description": "Short capability summary",
                    "maxLength": 256,
                    "type": "string"
                  },
                  "url": {
                    "description": "Related route URL",
                    "format": "uri",
                    "maxLength": 512,
                    "type": "string"
                  }
                },
                "required": [
                  "bridge",
                  "url",
                  "docs",
                  "summary"
                ],
                "type": "object"
              },
              "maxItems": 3,
              "type": "array"
            }
          },
          "required": [
            "docs"
          ],
          "type": "object"
        },
        "algorithm_version": {
          "const": "rfc7638-public-jwk-inspect-v1",
          "description": "Pinned public JWK and thumbprint contract",
          "type": "string"
        },
        "key_count": {
          "description": "Number of validated public keys",
          "maximum": 32,
          "minimum": 1,
          "type": "integer"
        },
        "keys": {
          "description": "Normalized public key metadata and thumbprints",
          "items": {
            "additionalProperties": false,
            "description": "Normalized validated public JWK metadata",
            "properties": {
              "alg": {
                "description": "Compatible advertised algorithm or empty; not a security endorsement",
                "type": "string"
              },
              "bits": {
                "description": "Validated public key or curve bit size",
                "maximum": 8192,
                "minimum": 256,
                "type": "integer"
              },
              "curve": {
                "description": "Validated curve or empty for RSA",
                "type": "string"
              },
              "key_ops": {
                "description": "Validated public operations",
                "items": {
                  "description": "verify operation",
                  "type": "string"
                },
                "maxItems": 1,
                "type": "array"
              },
              "kid": {
                "description": "Public key identifier or empty",
                "type": "string"
              },
              "kty": {
                "description": "Validated key type",
                "type": "string"
              },
              "thumbprint_sha256": {
                "description": "RFC 7638 SHA-256 JWK Thumbprint in base64url form",
                "pattern": "^[A-Za-z0-9_-]{43}$",
                "type": "string"
              },
              "use": {
                "description": "Validated sig use or empty",
                "type": "string"
              },
              "warnings": {
                "description": "Key-local certificate URL/chain handling warnings",
                "items": {
                  "description": "Human-readable warning",
                  "type": "string"
                },
                "maxItems": 8,
                "type": "array"
              }
            },
            "required": [
              "kty",
              "kid",
              "use",
              "key_ops",
              "alg",
              "curve",
              "bits",
              "thumbprint_sha256",
              "warnings"
            ],
            "type": "object"
          },
          "maxItems": 32,
          "minItems": 1,
          "type": "array"
        },
        "kind": {
          "description": "Selected request branch",
          "enum": [
            "single",
            "set"
          ],
          "type": "string"
        },
        "operation": {
          "const": "jwk-inspect",
          "description": "Stable operation name",
          "type": "string"
        },
        "warnings": {
          "description": "Route-level trust and suitability limitations",
          "items": {
            "description": "Human-readable warning",
            "type": "string"
          },
          "maxItems": 8,
          "type": "array"
        }
      },
      "required": [
        "operation",
        "algorithm_version",
        "kind",
        "key_count",
        "keys",
        "warnings"
      ],
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}

Example shape — generated from the schema, not a captured live response

{
  "example": {
    "_atlas": {
      "docs": "https://example.com",
      "related": [
        {
          "bridge": "string",
          "docs": "https://example.com",
          "summary": "string",
          "url": "https://example.com"
        }
      ]
    },
    "algorithm_version": "string",
    "key_count": 0,
    "keys": [
      {
        "alg": "string",
        "bits": 0,
        "curve": "string",
        "key_ops": [
          "string"
        ],
        "kid": "string",
        "kty": "string",
        "thumbprint_sha256": "string",
        "use": "string",
        "warnings": [
          "string"
        ]
      }
    ],
    "kind": "single",
    "operation": "string",
    "warnings": [
      "string"
    ]
  },
  "type": "string"
}

Examples

curl

curl "https://artifact-inspector.use.x402atlas.com/jwk"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

JavaScript

const res = await fetch("https://artifact-inspector.use.x402atlas.com/jwk");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

Python

import httpx
res = httpx.get("https://artifact-inspector.use.x402atlas.com/jwk")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header

Details

Provider: artifact-inspector.use.x402atlas.com
Endpoint: https://artifact-inspector.use.x402atlas.com/jwk
Machine-readable: /resources/28641.json