Payments · x402 · early usage

x402 Endpoint Payment Check

by app.tenna.ai · discovered, not yet claimed by its owner · updated 2026-10-06

30d calls4

30d payers3

MethodPOST

Outputjson

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

x402 Endpoint Payment Check. Check an x402 endpoint's 402 payment-required body before you rely on it. Reports whether the contract is payable, whether it is opted in to the Bazaar catalogue, and whether a buying agent can read its input schema by machine. Every defect carries a JSON evidence path. Reads the body you supply; it does not pay or call the endpoint. A PASS is not a correctness guarantee and not a claim that the service is accurate.

Tags: x402 · 402 · payment · audit · bazaar

Call contract

Method: POST
Input: json
Output: json
Last paid call: 2026-10-06

Input example from Bazaar metadata

{
  "offering": "x402_endpoint_lint",
  "paymentRequiredBody": {
    "accepts": [
      {
        "scheme": "exact"
      }
    ],
    "resource": {
      "description": "what it sells",
      "url": "https://example/api"
    },
    "x402Version": 2
  }
}

Output example

{
  "dataState": "<dataState>",
  "findings": [
    {}
  ],
  "grade": "PASS",
  "indexable": true,
  "limitations": [
    "<limitations>"
  ],
  "offering": "x402_endpoint_lint",
  "payable": true,
  "provenance": {
    "auditedDeliverableHash": null,
    "generatedAt": 1,
    "ledgerLaunchCount": null,
    "ledgerSpanHours": null,
    "resultHash": null,
    "rubricVersion": null,
    "source": "<source>"
  },
  "schemaVersion": "<schemaVersion>"
}

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/26980.json for the price and payment options.
Pay. Call GET https://app.tenna.ai/api/x402/verifier/x402_endpoint_lint. 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, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.01 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base
Demand: 4 calls · 3 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

Scheme	Network	Asset	Amount	Pay to	Timeout
exact	Base eip155:8453	USDC	$0.01	0x7eaf3c393a8996e124c0fa7ccbc55019854c4c5b	60s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x7eaf3c393a8996e124c0fa7ccbc55019854c4c5b",
    "asset": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
    "amount": "10000",
    "amountUsd": 0.01,
    "maxTimeoutSeconds": 60
  }
]

Schemas

Output schema (JSON Schema)

{
  "properties": {
    "example": {
      "additionalProperties": true,
      "properties": {
        "auditedBodyHash": {
          "description": "Hash of the 402 body we audited, so the same input can be re-run and this verdict reproduced. Null when no body was supplied.",
          "type": [
            "string",
            "null"
          ]
        },
        "dataState": {
          "description": "COMPLETE when the body was readable.",
          "type": "string"
        },
        "doNotReconcile": {
          "description": "Field pairs that describe independent failure modes and must not be cross-checked against each other; a difference between such a pair is expected and is not a contradiction.",
          "items": {
            "type": "object"
          },
          "type": "array"
        },
        "findings": {
          "description": "Defects, each with a JSON evidence path and a recommended fix. Severity is major (would stop a paying agent or block catalogue listing) or minor.",
          "items": {
            "type": "object"
          },
          "type": "array"
        },
        "grade": {
          "description": "Deterministic grade.",
          "enum": [
            "PASS",
            "WARN",
            "FAIL"
          ],
          "type": "string"
        },
        "indexable": {
          "description": "False when the Bazaar opt-in is missing, so the endpoint never appears in the catalogue however many payments settle.",
          "type": "boolean"
        },
        "limitations": {
          "description": "Coverage limits and missing data, always disclosed.",
          "items": {
            "type": "string"
          },
          "type": "array"
        },
        "machineReadableContract": {
          "description": "False when a non-standard schema keyword downgrades the published schema to a string, so a buying agent cannot read the contract.",
          "type": "boolean"
        },
        "offering": {
          "const": "x402_endpoint_lint",
          "description": "Offering that produced this result.",
          "type": "string"
        },
        "payable": {
          "description": "False when a defect would make settlement fail, such as a string over the facilitator's 500-character limit.",
          "type": "boolean"
        },
        "provenance": {
          "description": "Reproducibility metadata so another agent can audit this.",
          "properties": {
            "auditedDeliverableHash": {
              "description": "Explicit alias for resultHash on deliverable-audit results; hashes the buyer-supplied input, not the audit envelope.",
              "type": [
                "string",
                "null"
              ]
            },
            "generatedAt": {
              "description": "Unix seconds.",
              "type": "integer"
            },
            "ledgerLaunchCount": {
              "description": "Launches in the ledger. Null when the offering is not derived from the launch ledger — this means not applicable, not collection failure.",
              "type": [
                "integer",
                "null"
              ]
            },
            "ledgerSpanHours": {
              "description": "Hours of history covered. Null when the offering is not derived from the launch ledger.",
              "type": [
                "number",
                "null"
              ]
            },
            "resultHash": {
              "description": "Hash of the audited input, so the same verdict can be reproduced. Present on audit offerings.",
              "type": [
                "string",
                "null"
              ]
            },
            "rubricVersion": {
              "description": "Rubric the verdict was produced under. Present on audit offerings.",
              "type": [
                "string",
                "null"
              ]
            },
            "source": {
              "description": "Data origin.",
              "type": "string"
            }
          },
          "type": "object"
        },
        "schemaVersion": {
          "description": "Deliverable contract version.",
          "type": "string"
        },
        "severityCounts": {
          "description": "Counts by severity. The scale has two levels only, major and minor; there is no critical level.",
          "type": "object"
        }
      },
      "required": [
        "schemaVersion",
        "offering",
        "provenance",
        "limitations",
        "dataState",
        "grade",
        "findings",
        "payable",
        "indexable"
      ],
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}

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

{
  "example": {
    "auditedBodyHash": "string",
    "dataState": "string",
    "doNotReconcile": [
      {}
    ],
    "findings": [
      {}
    ],
    "grade": "PASS",
    "indexable": true,
    "limitations": [
      "string"
    ],
    "machineReadableContract": true,
    "offering": "string",
    "payable": true,
    "provenance": {
      "auditedDeliverableHash": "string",
      "generatedAt": 0,
      "ledgerLaunchCount": 0,
      "ledgerSpanHours": 0,
      "resultHash": "string",
      "rubricVersion": "string",
      "source": "string"
    },
    "schemaVersion": "string",
    "severityCounts": {}
  },
  "type": "string"
}

Examples

curl

curl "https://app.tenna.ai/api/x402/verifier/x402_endpoint_lint"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

JavaScript

const res = await fetch("https://app.tenna.ai/api/x402/verifier/x402_endpoint_lint");
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://app.tenna.ai/api/x402/verifier/x402_endpoint_lint")
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: app.tenna.ai
Endpoint: https://app.tenna.ai/api/x402/verifier/x402_endpoint_lint
Machine-readable: /resources/26980.json