17trust / 100

Agent Intel Agent Json Schema Guard

by SiteCheck Agent Intel & Dev in Other

x402 APIFailing, checked 4 h ago

Checks an agent's JSON output against a JSON Schema (draft 2020-12 keywords: type, properties, required, additionalProperties, items, enum, const, length, pattern, minimum/maximum, item counts). Returns valid yes/no, each error with its path and the value with disallowed fields removed. $ref, allOf/anyOf/oneOf, if/then and format return an error instead of passing silently.

POST
https://api.fadeandco.workers.dev/api/agent-intel/agent-json-schema-guard
Price
$0.001
per call in USDC
Uptime
0.0%
last 30 days
Response time
-
no timed checks yet
Last check
Failed
4 h ago, next any minute now

Run a free test callHow to call it

Reliability

All checks passedSome failedAll failedNot checked

Latest check failed 4 h ago: Amount "0.002" is not in atomic token units

Status and outage history · Atom feed · Watch with other listings

How to call it

POST https://api.fadeandco.workers.dev/api/agent-intel/agent-json-schema-guard

Each call costs $0.001 in USDC on Base, paid with the request over x402.

Run a free test callOne unpaid request, the way an agent sends it. You see the payment challenge it gets back. Nothing is charged.

Example request

From the listing.

POST https://api.fadeandco.workers.dev/api/agent-intel/agent-json-schema-guard
content-type: application/json

{
  "schema": {
    "additionalProperties": false,
    "properties": {
      "age": {
        "minimum": 0,
        "type": "integer"
      },
      "name": {
        "maxLength": 40,
        "type": "string"
      }
    },
    "required": [
      "name"
    ],
    "type": "object"
  },
  "value": {
    "age": 36,
    "extra": "remove me",
    "name": "Ada"
  }
}

Parameters

ParameterTypeRequiredDescription
schemaobjectYesThe JSON Schema
valueanyYesThe JSON value to check (any JSON)

Example response

The provider's example. We can't check it without paying.

{
  "checkedAt": "2026-10-23T09:35:20.029Z",
  "errors": [],
  "note": "Subset of JSON Schema 2020-12. Unsupported keywords are rejected, not ignored.",
  "removedFields": [
    "/extra"
  ],
  "sanitized": {
    "age": 36,
    "name": "Ada"
  },
  "source": "https://json-schema.org/draft/2020-12",
  "valid": true
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.001.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://api.fadeandco.workers.dev/api/agent-intel/agent-json-schema-guard' \
  -H 'content-type: application/json' \
  --data-raw '{"schema":{"additionalProperties":false,"properties":{"age":{"minimum":0,"type":"integer"},"name":{"maxLength":40,"type":"string"}},"required":["name"],"type":"object"},"value":{"age":36,"extra":"remove me","name":"Ada"}}'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - -X POST 'https://api.fadeandco.workers.dev/api/agent-intel/agent-json-schema-guard' \
  -H 'content-type: application/json' \
  --data-raw '{"schema":{"additionalProperties":false,"properties":{"age":{"minimum":0,"type":"integer"},"name":{"maxLength":40,"type":"string"}},"required":["name"],"type":"object"},"value":{"age":36,"extra":"remove me","name":"Ada"}}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode
JavaScript: pay and call
// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.001 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.001" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.001 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.fadeandco.workers.dev%2Fapi%2Fagent-intel%2Fagent-json-schema-guard&method=POST
const res = await pay("https://api.fadeandco.workers.dev/api/agent-intel/agent-json-schema-guard", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "schema": {
      "additionalProperties": false,
      "properties": {
        "age": {
          "minimum": 0,
          "type": "integer"
        },
        "name": {
          "maxLength": 40,
          "type": "string"
        }
      },
      "required": [
        "name"
      ],
      "type": "object"
    },
    "value": {
      "age": 36,
      "extra": "remove me",
      "name": "Ada"
    }
  }),
});
console.log(res.status, await res.text());
Python: pay and call
# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.001 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.001"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://api.fadeandco.workers.dev/api/agent-intel/agent-json-schema-guard",
        json={
            "schema": {
                "additionalProperties": False,
                "properties": {
                    "age": {
                        "minimum": 0,
                        "type": "integer",
                    },
                    "name": {
                        "maxLength": 40,
                        "type": "string",
                    },
                },
                "required": [
                    "name",
                ],
                "type": "object",
            },
            "value": {
                "age": 36,
                "extra": "remove me",
                "name": "Ada",
            },
        },
    )
    print(res.status_code, res.text)

Security scan

No findings

We scan names, descriptions and tool definitions for hidden instructions and other prompt-injection patterns.

Recent checks

WhenResultHTTPTimePrice
4 h agoAmount "0.002" is not in atomic token units402796 ms$0.002
12 h agoAmount "0.002" is not in atomic token units402160 ms$0.002
21 h agoAmount "0.002" is not in atomic token units40249 ms$0.002
29 h agoAmount "0.002" is not in atomic token units40289 ms$0.002
37 h agoAmount "0.002" is not in atomic token units40244 ms$0.002
Show 10 older checks
45 h agoAmount "0.002" is not in atomic token units4021.0 s$0.002
2 days agoAmount "0.002" is not in atomic token units4021.0 s$0.002
3 days agoAmount "0.002" is not in atomic token units402105 ms$0.002
3 days agoAmount "0.002" is not in atomic token units4021.4 s$0.002
3 days agoAmount "0.002" is not in atomic token units402152 ms$0.002
3 days agoAmount "0.002" is not in atomic token units40246 ms$0.002
4 days agoAmount "0.002" is not in atomic token units402103 ms$0.002
4 days agoAmount "0.001" is not in atomic token units402686 ms$0.001
4 days agoAmount "0.001" is not in atomic token units40241 ms$0.001
5 days agoAmount "0.001" is not in atomic token units402105 ms$0.001