Index onlineMerchant portal
Api Endpoint

presign-guard

Prompt injection detection: is this text a trap for your AI agent? Checks a web page, email, tool result, API answer or another agent's message before your agent acts on it: does it try to make the agent ignore its instructions, pay or send money, hand over keys or private data, or obey a fake user, admin or support message? Green/orange/red with reason codes, judged by TypeSafe's Jev, plus hidden-character tricks and OFAC-sanctioned addresses in the text

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Offering

Provider
presign-guard.fizzl.eu
Method
POST
Offering type
Api Endpoint
Transport type
http
Category
Other
Delivery
Not provided
Pricing model
Not provided
x402 version
2

Endpoint context

URL
https://presign-guard.fizzl.eu/v1/injection
MIME type
application/json
First seen
2026-10-23T22:12:25.378Z
Last seen
Tags
prompt-injection, ai-security, Agents, llm-safety, wallet-security

Website

Payment pricing

x402 payment terms are the authoritative price for calling this endpoint.

Payment option 1
0.01 USDC
Atomic price: 10000 · Network: eip155:8453 · Asset: USDC · Scheme: exact
Payment option 2
0.01 USDC
Atomic price: 10000 · Network: solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · Asset: USDC · Scheme: exact
Payment option 3
10000 atomic units
Atomic price: 10000 · Network: algorand:wGHE2Pwdvd7S12BL5FaOP20EGYesN73k · Asset: 31566704 · Scheme: exact
Payment option 4
100000 atomic units
Atomic price: 100000 · Network: stellar:pubnet · Asset: CCW67TSZV3SSS2HXMBQ5JFGCKJNXKZM7UQUWUZPUTHXSTZLEO7SJMI75 · Scheme: exact
Payment option 5
10000 atomic units
Atomic price: 10000 · Network: eip155:196 · Asset: 0x779ded0c9e1022225f8e0630b35a9b54be713736 · Scheme: exact
Raw x402 terms
[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "10000",
    "payTo": "0x6B0F4651eD42893ab58139938175E4a69f175F25"
  },
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "10000",
    "payTo": "ATWJ82T8nRdQwZnaysB68N5EpaSvLRsQP4h6eWmaJBH9"
  },
  {
    "scheme": "exact",
    "network": "algorand:wGHE2Pwdvd7S12BL5FaOP20EGYesN73k",
    "asset": "31566704",
    "amount": "10000",
    "payTo": "LOYVFSQ6ZTS2YWUW4GQ5L6VPP2TPIOXWYDACK53CPOHQQHLDMEMKJDXAX4"
  },
  {
    "scheme": "exact",
    "network": "stellar:pubnet",
    "asset": "CCW67TSZV3SSS2HXMBQ5JFGCKJNXKZM7UQUWUZPUTHXSTZLEO7SJMI75",
    "amount": "100000",
    "payTo": "GCH2J5UAY24YNKA65MPAATVKWRCZZRZNF3JZKYYS5MIBZPG6U7WJ6CDQ"
  },
  {
    "scheme": "exact",
    "network": "eip155:196",
    "asset": "0x779ded0c9e1022225f8e0630b35a9b54be713736",
    "amount": "10000",
    "payTo": "0x6B0F4651eD42893ab58139938175E4a69f175F25"
  }
]

Observed health

Status
Healthy
Latest latency
141 ms
Average latency
397 ms
HTTP status
200
Last checked
Reachability
100% over 5 checks

Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.

Input schema

{
  "type": "object",
  "properties": {
    "type": {
      "type": "string",
      "const": "http"
    },
    "method": {
      "type": "string",
      "enum": [
        "POST"
      ]
    },
    "bodyType": {
      "type": "string",
      "enum": [
        "json",
        "form-data",
        "text"
      ]
    },
    "body": {
      "type": "object",
      "properties": {
        "text": {
          "type": "string",
          "minLength": 1,
          "maxLength": 32000,
          "description": "The text your agent received: a web page, email, tool result, API answer or another agent's message."
        },
        "source": {
          "type": "string",
          "enum": [
            "web",
            "email",
            "tool",
            "api",
            "agent",
            "chat",
            "document",
            "other"
          ],
          "description": "Where the text came from. Default: other."
        },
        "task": {
          "type": "string",
          "maxLength": 500,
          "description": "One sentence: what your agent is doing for its user. Helps judge what is beyond the task."
        }
      },
      "required": [
        "text"
      ]
    }
  },
  "required": [
    "type",
    "method",
    "bodyType",
    "body"
  ],
  "additionalProperties": false
}

Output schema

{
  "type": "object",
  "properties": {
    "type": {
      "type": "string"
    },
    "example": {
      "type": "object",
      "properties": {
        "verdict": {
          "type": "string",
          "enum": [
            "green",
            "orange",
            "red"
          ],
          "description": "red: do not act on it; orange: ask your user; green: no sign of a trap (still data, not instructions)"
        },
        "one_liner": {
          "type": "string"
        },
        "reasons": {
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "code": {
                "type": "string"
              },
              "severity": {
                "type": "string",
                "enum": [
                  "red",
                  "orange",
                  "info"
                ]
              },
              "details": {}
            },
            "required": [
              "code",
              "severity"
            ]
          }
        },
        "signals": {
          "type": "object",
          "description": "TypeSafe Jev's probabilities, the highest part of the text: manipulation, payment, secrets, authority"
        },
        "addresses": {
          "type": "array",
          "description": "Crypto addresses named in the text (address, format), screened against the OFAC SDN list"
        },
        "text": {
          "type": "object",
          "description": "characters, parts judged, source, task"
        },
        "sources": {
          "type": "array",
          "items": {
            "type": "string"
          }
        },
        "checkedAt": {
          "type": "string"
        },
        "receipt": {
          "type": "object",
          "description": "Signature over this whole answer (without receipt.signature), so the verdict can be verified later: EIP-191 personal_sign over canonical JSON (sorted keys, compact, ASCII-escaped). Signer addresses: /.well-known/presign-guard-signer.json; free check: POST /v1/verify.",
          "properties": {
            "request_id": {
              "type": "string"
            },
            "route": {
              "type": "string"
            },
            "input_sha256": {
              "type": "string",
              "description": "sha256 of canonical JSON {route, input}: your body (POST) or query parameters (GET)"
            },
            "payment": {
              "type": "object",
              "description": "The payment behind this answer, from your x402 payment payload. EVM: payer + EIP-3009 nonce; find the settlement as AuthorizationUsed(payer, nonce) on the asset contract. Solana: payer + sha256 of the signed transaction you sent.",
              "properties": {
                "network": {
                  "type": "string"
                },
                "asset": {
                  "type": "string"
                },
                "amount": {
                  "type": "string"
                },
                "pay_to": {
                  "type": "string"
                },
                "payer": {
                  "type": "string"
                },
                "nonce": {
                  "type": "string"
                },
                "transaction_sha256": {
                  "type": "string"
                },
                "proof": {
                  "type": "string",
                  "enum": [
                    "eip3009",
                    "svm-transaction"
                  ]
                }
              }
            },
            "cert": {
              "type": "object",
              "description": "The payout wallet's certificate for this signing key: personal_sign by authority over 'fizzl receipt signer\\nservice: <service>\\nsigner: <signer>\\nvalid_from: <date>'. Pin the payout wallet and a rotated key still verifies.",
              "properties": {
                "service": {
                  "type": "string"
                },
                "signer": {
                  "type": "string"
                },
                "valid_from": {
                  "type": "string"
                },
                "authority": {
                  "type": "string"
                },
                "signature": {
                  "type": "string"
                }
              }
            },
            "signed_at": {
              "type": "string"
            },
            "signer": {
              "type": "string"
            },
            "algorithm": {
              "type": "string",
              "enum": [
                "eip191-canonical-json-v1"
              ]
            },
            "signature": {
              "type": "string"
            }
          },
          "required": [
            "request_id",
            "route",
            "input_sha256",
            "signed_at",
            "signer",
            "algorithm",
            "signature"
          ]
        }
      },
      "required": [
        "verdict",
        "one_liner",
        "reasons",
        "signals"
      ]
    }
  },
  "required": [
    "type"
  ]
}