[MCP: optimize_context] Pay-per-call JSON context pruning & LLM token budget enforcement

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xA18E34607479b706123cA5e1831f24d2ECECe4c6",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "1000",
    "maxTimeoutSeconds": 604800
  }
]

{
  "bazaar": {
    "info": {
      "input": {
        "body": {
          "data": {}
        },
        "bodyType": "json",
        "method": "POST",
        "type": "http"
      },
      "output": {
        "example": {
          "metrics": {
            "originalTokens": 622,
            "reductionPercentage": "84.9%",
            "savedTokens": 528,
            "slimmedTokens": 94,
            "strategyApplied": "prune_arrays"
          },
          "result": {},
          "status": "success",
          "toolResultReference": {
            "expiresIn": "3600s",
            "fetchTool": "fetch_result",
            "referenceId": "ref_12345678"
          }
        },
        "type": "json"
      }
    },
    "schema": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "properties": {
        "input": {
          "additionalProperties": false,
          "properties": {
            "body": {
              "type": "object"
            },
            "bodyType": {
              "const": "json",
              "type": "string"
            },
            "method": {
              "enum": [
                "POST",
                "PUT",
                "PATCH"
              ],
              "type": "string"
            },
            "type": {
              "const": "http",
              "type": "string"
            }
          },
          "required": [
            "type",
            "method",
            "bodyType",
            "body"
          ],
          "type": "object"
        },
        "output": {
          "properties": {
            "example": {
              "type": "object"
            },
            "type": {
              "type": "string"
            }
          },
          "required": [
            "type"
          ],
          "type": "object"
        }
      },
      "required": [
        "input"
      ],
      "type": "object"
    }
  }
}

curl "https://contextslim.friczero.com/message"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

const res = await fetch("https://contextslim.friczero.com/message");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

import httpx
res = httpx.get("https://contextslim.friczero.com/message")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header