561 Group Market

FOUR Evidence Truth Conjunction

Meet up to 14627 FOUR points in truth order: told-for iff every input tells for, told-against iff any tells against. Inputs must share a family; empty input returns the existing vacuous unit potential in the knowledge family. No Boolean collapse or witness creation.

Price
$0.002 USDC per request
Network
Base mainnet, eip155:8453, settled in USDC through the Coinbase CDP facilitator
Method and URL
POST https://market.561.group/v1/four/reading-truth-meet
Response type
application/json
Seller
Causeway Services (561 Group)

Input contract

Input that fails this contract is refused with a 4xx status before any payment is requested.

{
  "maxBytes": 102400,
  "bodySchema": {
    "type": "object",
    "additionalProperties": true,
    "required": [
      "names"
    ],
    "properties": {
      "names": {
        "type": "array",
        "maxItems": 14627,
        "items": {
          "type": "string",
          "enum": [
            "absurd",
            "potential",
            "active",
            "stable",
            "told none",
            "told true",
            "told false",
            "told both",
            "neither",
            "true",
            "false",
            "both",
            "unknown",
            "held",
            "denied",
            "contested"
          ]
        }
      }
    }
  }
}

Example request

{
  "method": "POST",
  "url": "https://market.561.group/v1/four/reading-truth-meet",
  "headers": {
    "accept": "application/json",
    "content-type": "application/json"
  },
  "body": {
    "names": [
      "held",
      "denied"
    ]
  }
}

Output

{
  "schema": {
    "type": "string",
    "enum": [
      "absurd",
      "potential",
      "active",
      "stable",
      "told none",
      "told true",
      "told false",
      "told both",
      "neither",
      "true",
      "false",
      "both",
      "unknown",
      "held",
      "denied",
      "contested"
    ]
  },
  "example": "denied"
}

How to buy with x402

  1. Send the request without payment. The server answers 402 Payment Required with a base64 JSON PAYMENT-REQUIRED header holding the amount, asset, network and payee.
  2. Have your wallet sign an EIP-3009 transferWithAuthorization for exactly those terms (an x402 client library does this for you).
  3. Repeat the identical request with the signed payload in the PAYMENT-SIGNATURE header.
  4. The server verifies, runs the operation, settles, and returns 200 with the result and a PAYMENT-RESPONSE header carrying the settlement receipt.

Read the price without paying

curl --include --request POST --header 'accept: application/json' --header 'content-type: application/json' --data-raw '{"names":["held","denied"]}' --url 'https://market.561.group/v1/four/reading-truth-meet'

This request authorizes nothing; it returns the live payment terms. Read the full explanation of x402.

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