Provably-fair verify API

Recomputes the HMAC-SHA256(serverSeed, clientSeed:nonce) outcome and converts it to a float, dice roll or bounded integer to verify a provably-fair gambling result. Answers 'Was this casino roll provably fair given the seeds?', 'What outcome does this server/client seed pair produce?'.

Price$0.04per request

MethodPOST

Route/v1/gametheory/provably-fair-verify

StatusLive

MIME typeapplication/json

Rate limit120/minute

Cache0s public

provably-fairhmacsha256verificationgamblingrngcasinocrypto

API URLhttps://x402.hexl.dev/v1/gametheory/provably-fair-verify

Integration docs

Example request

{
  "serverSeed": "serverSeed123",
  "clientSeed": "clientSeed456",
  "nonce": 0,
  "mode": "float"
}

Example response

{
  "serverSeed": "serverSeed123",
  "clientSeed": "clientSeed456",
  "nonce": 0,
  "message": "clientSeed456:0",
  "hmacSha256": "39cc7e8cc7336f20ce6c58c0140db1a4a0f90a4547517afdd771bd85a59ebc3a",
  "leadingHex": "39cc7e8c",
  "intValue": 969703052,
  "float": 0.2257765858,
  "mode": "float",
  "outcome": 0.2257765858,
  "interpretation": "HMAC-SHA256(serverSeed, \"clientSeed456:0\") = 39cc7e8cc7336f20… → float in [0,1) = 0.2257765858. Recompute to confirm the operator did not tamper with the result."
}

Input schema

{
  "type": "object",
  "required": [
    "serverSeed",
    "clientSeed"
  ],
  "properties": {
    "serverSeed": {
      "type": "string",
      "examples": [
        "serverSeed123"
      ]
    },
    "clientSeed": {
      "type": "string",
      "examples": [
        "clientSeed456"
      ]
    },
    "nonce": {
      "type": "integer",
      "minimum": 0,
      "examples": [
        0
      ]
    },
    "mode": {
      "type": "string",
      "enum": [
        "float",
        "dice",
        "int"
      ],
      "examples": [
        "float"
      ]
    },
    "max": {
      "type": "integer",
      "minimum": 1
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}