Base64 in both directions, including the URL-safe alphabet, with UTF-8 handled properly

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "2500",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:137",
    "payTo": "0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff",
    "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
    "amount": "2500",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:42161",
    "payTo": "0xc210Ea7D5692a6401ADf25BbCB7aCDe9cDB7e9Ff",
    "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
    "amount": "2500",
    "maxTimeoutSeconds": 300
  }
]

{
  "bazaar": {
    "info": {
      "input": {
        "method": "GET",
        "queryParams": {
          "input": "hello world",
          "mode": "encode"
        },
        "type": "http"
      },
      "output": {
        "example": {
          "mode": "encode",
          "result": "aGVsbG8gd29ybGQ="
        },
        "type": "json"
      }
    },
    "schema": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "properties": {
        "input": {
          "additionalProperties": false,
          "properties": {
            "method": {
              "enum": [
                "GET"
              ],
              "type": "string"
            },
            "queryParams": {
              "properties": {
                "input": {
                  "description": "The text or base64 to convert.",
                  "type": "string"
                },
                "mode": {
                  "description": "encode | decode. Defaults to encode.",
                  "type": "string"
                },
                "urlSafe": {
                  "description": "Use the URL-safe alphabet (-_ instead of +/).",
                  "type": "boolean"
                }
              },
              "required": [
                "input"
              ],
              "type": "object"
            },
            "type": {
              "const": "http",
              "type": "string"
            }
          },
          "required": [
            "type",
            "method"
          ],
          "type": "object"
        },
        "output": {
          "properties": {
            "example": {
              "type": "object"
            },
            "type": {
              "type": "string"
            }
          },
          "required": [
            "type"
          ],
          "type": "object"
        }
      },
      "required": [
        "input"
      ],
      "type": "object"
    }
  }
}

curl "https://flat-rate-llm.kikoribera03.workers.dev/v1/util/base64"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

const res = await fetch("https://flat-rate-llm.kikoribera03.workers.dev/v1/util/base64");
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://flat-rate-llm.kikoribera03.workers.dev/v1/util/base64")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header