Predge · Signed Attestations

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"
    },
    "payTo": "0x9084f5000e07c7133d6da5ee4f271ab6d1821144",
    "amount": "20000",
    "scheme": "exact",
    "network": "eip155:8453",
    "mimeType": "application/json",
    "resource": "https://x402-api-production-266e.up.railway.app/v1/kalshi/attest/:ticker",
    "description": "Cryptographically SIGNED settled-KALSHI-outcome ATTESTATION for one market (path param: ticker, a Kalshi market ticker). Returns the market's SETTLED resolution (resolved, resolution yes|no, resolved_at) as an ed25519-signed envelope verifiable OFFLINE against the SAME published key as /v1/attest. Optional query param: side (yes|no) — adds correct (true iff it matches the resolution, null while unsettled). Data source: Kalshi's public market API (no key, no account); this attests the MARKET's own result, NOT trader data. A market that exists but has not settled returns resolved:false. 404 (not charged) for an unknown ticker.",
    "maxAmountRequired": "20000",
    "maxTimeoutSeconds": 60
  },
  {
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "extra": {},
    "payTo": "9dxMRRtC7RKZH5rFZpUywjmnQ87H9qHhtW43u5LYmpV",
    "amount": "20000",
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "mimeType": "application/json",
    "resource": "https://x402-api-production-266e.up.railway.app/v1/kalshi/attest/:ticker",
    "description": "Cryptographically SIGNED settled-KALSHI-outcome ATTESTATION for one market (path param: ticker, a Kalshi market ticker). Returns the market's SETTLED resolution (resolved, resolution yes|no, resolved_at) as an ed25519-signed envelope verifiable OFFLINE against the SAME published key as /v1/attest. Optional query param: side (yes|no) — adds correct (true iff it matches the resolution, null while unsettled). Data source: Kalshi's public market API (no key, no account); this attests the MARKET's own result, NOT trader data. A market that exists but has not settled returns resolved:false. 404 (not charged) for an unknown ticker.",
    "maxAmountRequired": "20000",
    "maxTimeoutSeconds": 60
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "type": "http",
        "queryParams": {
          "side": "yes"
        }
      },
      "output": {
        "type": "json",
        "example": {
          "kind": "kalshi-resolution",
          "issuer": "predge.io",
          "verify": "ed25519: verify `signature` (hex) over the UTF-8 bytes of `canonical` using `public_key` (hex, raw 32-byte ed25519). `canonical` is JSON with keys sorted lexicographically and no whitespace.",
          "correct": true,
          "payload": {
            "kind": "kalshi-resolution",
            "issuer": "predge.io",
            "source": "kalshi",
            "ticker": "KXPRESPARTY-28-R",
            "correct": true,
            "version": "predge-attest-v1",
            "resolved": true,
            "issued_at": "2026-07-29T10:00:00.000Z",
            "resolution": "yes",
            "resolved_at": "2026-07-29T12:45:00Z",
            "queried_side": "yes"
          },
          "version": "predge-attest-v1",
          "algorithm": "ed25519",
          "canonical": "{\"correct\":true,\"issued_at\":\"2026-07-29T10:00:00.000Z\",\"issuer\":\"predge.io\",\"kind\":\"kalshi-resolution\",\"queried_side\":\"yes\",\"resolution\":\"yes\",\"resolved\":true,\"resolved_at\":\"2026-07-29T12:45:00Z\",\"source\":\"kalshi\",\"ticker\":\"KXPRESPARTY-28-R\",\"version\":\"predge-attest-v1\"}",
          "signature": "3a1f…64-byte-hex…9c",
          "data_basis": "Settled market resolution from Kalshi's public market API (result yes|no). Outcome-verified truth, not a prediction — signed so a consumer can verify it offline.",
          "public_key": "d75a9807...c7e2a1",
          "queried_side": "yes",
          "outcome_verified": true
        }
      }
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method"
          ],
          "properties": {
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "enum": [
                "GET",
                "HEAD",
                "DELETE"
              ],
              "type": "string"
            },
            "queryParams": {
              "type": "object",
              "properties": {
                "side": {
                  "enum": [
                    "yes",
                    "no"
                  ],
                  "type": "string",
                  "description": "Optional side to check correctness for"
                }
              }
            }
          },
          "additionalProperties": false
        },
        "output": {
          "type": "object",
          "required": [
            "type"
          ],
          "properties": {
            "type": {
              "type": "string"
            },
            "example": {
              "type": "object"
            }
          }
        }
      }
    }
  }
}

Provenance

Seen in the source catalog

—

Last indexed by Roundhouse

2026-09-21 22:15Z

Last enriched (probe, favicon, geo)

2026-09-21 22:45Z

x402 version

2

Max timeout

60s

Liveness probe

HTTP 400