api.limitguard.ai

Live 402 challenge

Captured by the enrichment pass, not read just now. Prices can change — always read the 402 the endpoint answers with.

{
  "error": "Payment Required",
  "accepts": [
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2",
        "decimals": 6
      },
      "payTo": "0x6454a645C92B8722EC9A07FCe12A582A877B8843",
      "amount": "5000",
      "scheme": "exact",
      "network": "eip155:8453",
      "mimeType": "application/json",
      "resource": "https://api.limitguard.ai/v1/seller/preflight",
      "description": "Preflight before an agent pays an x402 seller: screens the payTo wallet against the OFAC SDN address list, reads who registered the resource domain and when (RDAP), and screens that company against the OFAC, EU and UN lists. Compares the payTo with the wallet the seller publishes in its 402 and /.well-known/x402, and blocks a lookalike (address poisoning). Returns ok, caution or block with one reason per finding.",
      "maxAmountRequired": "5000",
      "maxTimeoutSeconds": 600
    },
    {
      "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
      "extra": {
        "name": "USDC",
        "version": "2",
        "decimals": 6,
        "feePayer": "2jMbAFjK2joDBaecvvNDBKU1BTyj3FuvV1ZTmvTkKQu8"
      },
      "payTo": "P9Mqh3W5sR5CqJAWYJFQePVaUs5GBfnonsaCdT7FbEQ",
      "amount": "5000",
      "scheme": "exact",
      "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
      "mimeType": "application/json",
      "resource": "https://api.limitguard.ai/v1/seller/preflight",
      "description": "Preflight before an agent pays an x402 seller: screens the payTo wallet against the OFAC SDN address list, reads who registered the resource domain and when (RDAP), and screens that company against the OFAC, EU and UN lists. Compares the payTo with the wallet the seller publishes in its 402 and /.well-known/x402, and blocks a lookalike (address poisoning). Returns ok, caution or block with one reason per finding.",
      "maxAmountRequired": "5000",
      "maxTimeoutSeconds": 600
    },
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "proof": "transactionHash",
        "header": "X-PAYMENT",
        "decimals": 6,
        "challengeId": "C0PfEgdd1ksFeoJXOB-ZTcqbCHhQDyOh",
        "paymentFlow": "upfront",
        "instructions": "Already sent the USDC? Transfer at least 5000 units to payTo on this network, then retry with '0x<64-hex transaction hash>' as your PAYMENT-SIGNATURE (x402 v2) or X-PAYMENT (v1) header AND the X-Payment-Challenge header from the payment-required response you were quoted this resource with (extra.challengeId there). The receipt is read on chain; the transfer must be within the last 150 blocks, each hash pays once, and only the caller that received that challenge can redeem it. Optionally also send X-Payment-Challenge-Signature: the sending wallet's signature over the challenge message (layout on the x402 protocol page). It is optional today and will become required; signing makes your hash unredeemable by anyone else. A redemption sent right after mining can be refused with errorCode settlement_not_yet_visible while our node catches up; the hash is not consumed, so wait for Retry-After and send the same request again.",
        "challengeHeader": "X-Payment-Challenge",
        "challengeSignatureHeader": "X-Payment-Challenge-Signature"
      },
      "payTo": "0x6454a645C92B8722EC9A07FCe12A582A877B8843",
      "amount": "5000",
      "scheme": "settled-transfer",
      "network": "eip155:8453",
      "mimeType": "application/json",
      "resource": "https://api.limitguard.ai/v1/seller/preflight",
      "description": "Preflight before an agent pays an x402 seller: screens the payTo wallet against the OFAC SDN address list, reads who registered the resource domain and when (RDAP), and screens that company against the OFAC, EU and UN lists. Compares the payTo with the wallet the seller publishes in its 402 and /.well-known/x402, and blocks a lookalike (address poisoning). Returns ok, caution or block with one reason per finding.",
      "maxAmountRequired": "5000",
      "maxTimeoutSeconds": 300
    }
  ],
  "resource": {
    "url": "https://api.limitguard.ai/v1/seller/preflight",
    "tags": [
      "kyb",
      "sanctions",
      "lead-verification",
      "wallet-screening",
      "compliance"
    ],
    "iconUrl": "https://limitguard.ai/icon-512.png",
    "mimeType": "application/json",
    "description": "Preflight before an agent pays an x402 seller: screens the payTo wallet against the OFAC SDN address list, reads who registered the resource domain and when (RDAP), and screens that company against the OFAC, EU and UN lists. Compares the payTo with the wallet the seller publishes in its 402 and /.well-known/x402, and blocks a lookalike (address poisoning). Returns ok, caution or block with one reason per finding.",
    "serviceName": "Limitguard"
  },
  "errorCode": "payment_required",
  "extensions": {
    "bazaar": {
      "info": {
        "input": {
          "body": {
            "pay_to": "0x7e4c2a91d05b3f68a1c9e2d4b7f05a3c6e81d290",
            "resource_url": "https://api.example.com/v1/data"
          },
          "type": "http",
          "method": "POST",
          "bodyType": "json"
        },
        "output": {
          "type": "json",
          "example": {
            "as_of": "2026-10-13T09:00:00+00:00",
            "domain": {
              "host": "api.example.com",
              "company": {
                "name": "Example B.V.",
                "country": "NL"
              },
              "rdap_domain": "example.com",
              "rdap_status": "ok",
              "registered_at": "2019-03-01"
            },
            "wallet": {
              "as_of": "2026-10-12",
              "lists": [],
              "status": "ok",
              "chain_id": "eip155:8453",
              "sanctioned": false,
              "address_redacted": "0x7e4c...d290"
            },
            "reasons": [],
            "sources": [
              "ofac_sdn_wallet_list",
              "rdap",
              "sanctions_name_lists",
              "seller_declared_payto"
            ],
            "verdict": "ok",
            "lookalike": {
              "status": "ok",
              "reasons": [
                "payto_matches_seller"
              ],
              "declared": "match",
              "payer_masked": null,
              "pay_to_masked": "0x7e4c...d290",
              "payer_history": "not_requested",
              "declared_masked": [
                "0x7e4c...d290"
              ],
              "declared_sources": [
                "payment_required"
              ],
              "previous_payee_masked": null
            },
            "not_checked": [
              "scam_lists",
              "x402_seller_lists",
              "wallet_history"
            ],
            "schema_version": "seller-preflight-v1",
            "company_sanctions": {
              "status": "no_match",
              "list_dates": {
                "EU": "2026-10-12",
                "UN": "2026-10-12",
                "OFAC SDN": "2026-10-12"
              },
              "lists_checked": [
                "OFAC SDN",
                "EU",
                "UN"
              ]
            }
          }
        },
        "sandbox": {
          "url": "https://api.limitguard.ai/v1/keys/create",
          "curl": "curl -s -X POST https://api.limitguard.ai/v1/keys/create -H 'Content-Type: application/json' -d '{\"email\": \"you@example.com\", \"tier\": \"sandbox\"}'",
          "note": "Free sandbox key, no wallet. POST here with tier=sandbox to get an lg_sandbox_ key; send it as X-API-Key for free mock data on the entity, risk, KYB, reputation and sanctions routes (10 req/min). Or sign up for 5 free lead checks (once per verified company, used within 30 days; a full report is paid): https://dashboard.limitguard.ai/sign-up?utm_source=api&utm_medium=agent&utm_campaign=signup&utm_content=x402_hint. Or screen a name against the OFAC, EU and UN sanctions lists free first: POST https://api.limitguard.ai/v1/sanctions/preview, or a wallet address against the OFAC SDN list: POST https://api.limitguard.ai/v1/sanctions/wallet."
        },
        "recovery": {
          "url": "https://api.limitguard.ai/v1/quickstart",
          "curl": "curl -s https://api.limitguard.ai/v1/quickstart"
        },
        "description": "Preflight before an agent pays an x402 seller: screens the payTo wallet against the OFAC SDN address list, reads who registered the resource domain and when (RDAP), and screens that company against the OFAC, EU and UN lists. Compares the payTo with the wallet the seller publishes in its 402 and /.well-known/x402, and blocks a lookalike (address poisoning). Returns ok, caution or block with one reason per finding.",
        "documentation_url": "https://docs.limitguard.ai/x402-protocol?utm_source=api&utm_medium=agent&utm_campaign=docs&utm_content=x402_protocol"
      },
      "schema": {
        "type": "object",
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "required": [
          "input"
        ],
        "properties": {
          "note": {
            "type": "string"
          },
          "input": {
            "type": "object",
            "required": [
              "type",
              "method",
              "bodyType",
              "body"
            ],
            "properties": {
              "body": {
                "type": "object",
                "required": [
                  "pay_to",
                  "resource_url"
                ],
                "properties": {
                  "payer": {
                    "type": "string",
                    "description": "Optional: your own paying wallet (EVM). Its previous USDC payees on Base are compared with pay_to"
                  },
                  "pay_to": {
                    "type": "string",
                    "description": "The payTo wallet of the x402 quote you are about to pay"
                  },
                  "network": {
                    "type": "string",
                    "description": "CAIP-2 network of the quote (default eip155:8453); eip155:* or solana:*"
                  },
                  "resource_url": {
                    "type": "string",
                    "description": "The https URL of the paid resource, on a public DNS name"
                  }
                }
              },
              "type": {
                "type": "string",
                "const": "http"
              },
              "method": {
                "enum": [
                  "POST",
                  "PUT",
                  "PATCH"
                ],
                "type": "string"
              },
              "headers": {
                "type": "object",
                "additionalProperties": {
                  "type": "string"
                }
              },
              "bodyType": {
                "enum": [
                  "json",
                  "form-data",
                  "text"
                ],
                "type": "string"
              },
              "queryParams": {
                "type": "object"
              }
            },
            "additionalProperties": false
          },
          "output": {
            "type": "object",
            "required": [
              "type"
            ],
            "properties": {
              "type": {
                "type": "string"
              },
              "example": {
                "type": "object"
              }
            }
          },
          "sandbox": {
            "type": "object",
            "required": [
              "url"
            ],
            "properties": {
              "url": {
                "type": "string"
              },
              "curl": {
                "type": "string"
              },
              "note": {
                "type": "string"
              }
            }
          },
          "recovery": {
            "type": "object",
            "required": [
              "url"
            ],
            "properties": {
              "url": {
                "type": "string"
              },
              "curl": {
                "type": "string"
              }
            }
          },
          "prepaidBalance": {
            "type": "object",
            "required": [
              "balance_usd",
              "price_usd"
            ],
            "properties": {
              "note": {
                "type": "string"
              },
              "topup": {
                "type": "object",
                "required": [
                  "url"
                ],
                "properties": {
                  "url": {
                    "type": "string"
                  },
                  "curl": {
                    "type": "string"
                  },
                  "minimum_usd": {
                    "type": "integer"
                  }
                }
              },
              "reason": {
                "type": "string"
              },
              "price_usd": {
                "type": "number"
              },
              "balance_usd": {
                "type": [
                  "number",
                  "null"
                ]
              }
            }
          },
          "documentation_url": {
            "type": "string"
          },
          "cachedTierAvailable": {
            "type": "boolean"
          }
        }
      }
    }
  },
  "x402Version": 2
}

Accepts

The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.

[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "name": "USD Coin",
      "version": "2",
      "decimals": 6
    },
    "payTo": "0x6454a645C92B8722EC9A07FCe12A582A877B8843",
    "scheme": "exact",
    "network": "eip155:8453",
    "mimeType": "application/json",
    "resource": "https://api.limitguard.ai/v1/seller/preflight",
    "description": "Preflight before an agent pays an x402 seller: screens the payTo wallet against the OFAC SDN address list, reads who registered the resource domain and when (RDAP), and screens that company against t…",
    "maxAmountRequired": "5000",
    "maxTimeoutSeconds": 600
  },
  {
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "extra": {
      "name": "USDC",
      "version": "2",
      "decimals": 6,
      "feePayer": "2jMbAFjK2joDBaecvvNDBKU1BTyj3FuvV1ZTmvTkKQu8"
    },
    "payTo": "P9Mqh3W5sR5CqJAWYJFQePVaUs5GBfnonsaCdT7FbEQ",
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "mimeType": "application/json",
    "resource": "https://api.limitguard.ai/v1/seller/preflight",
    "description": "Preflight before an agent pays an x402 seller: screens the payTo wallet against the OFAC SDN address list, reads who registered the resource domain and when (RDAP), and screens that company against t…",
    "maxAmountRequired": "5000",
    "maxTimeoutSeconds": 600
  }
]

Provenance

Seen in the source catalog

2026-10-14 08:34Z

Last indexed by Roundhouse

2026-10-25 19:46Z

Last enriched (probe, favicon, geo)

2026-10-19 14:45Z

x402 version

1

Max timeout

600s

Liveness probe

HTTP 402