{
  "x402Version": 2,
  "id": 37838,
  "slug": "37838",
  "resource": "https://mcp.dropenginehq.com/api/simulate-transaction",
  "description": "Simulates an unsigned Base or Base Sepolia EVM transaction with read-only RPC calls before an agent signs or broadcasts it. Returns execution/revert status, gas estimate, decoded top-level ERC-20 transfers and approvals, unlimited-approval warnings, and a risk signal. It never signs, holds keys, or broadcasts. Standard RPC does not expose complete internal/token state diffs.",
  "type": "http",
  "serviceName": "Transaction Preflight",
  "resourceType": "MCP Tool",
  "accepts": [
    {
      "scheme": "exact",
      "network": "eip155:8453",
      "payTo": "0xc7693f1ba43E6D1F1885292E1194dc1FDc6e7585",
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "amount": "20000",
      "amountUsd": 0.02,
      "maxTimeoutSeconds": 300
    }
  ],
  "extensions": {
    "bazaar": {
      "info": {
        "input": {
          "body": {
            "chain": "base",
            "data": "0x",
            "from": "0x1111111111111111111111111111111111111111",
            "to": "0x1111111111111111111111111111111111111111",
            "value": "0"
          },
          "bodyType": "json",
          "method": "POST",
          "type": "http"
        }
      },
      "schema": {
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "properties": {
          "input": {
            "additionalProperties": false,
            "properties": {
              "body": {
                "additionalProperties": false,
                "properties": {
                  "chain": {
                    "description": "Base mainnet, or Base Sepolia for test transactions.",
                    "enum": [
                      "base",
                      "base-sepolia"
                    ],
                    "type": "string"
                  },
                  "data": {
                    "description": "Unsigned transaction calldata; no signing material.",
                    "maxLength": 131074,
                    "pattern": "^0x([a-fA-F0-9]{2})*$",
                    "type": "string"
                  },
                  "from": {
                    "pattern": "^0x[a-fA-F0-9]{40}$",
                    "type": "string"
                  },
                  "to": {
                    "pattern": "^0x[a-fA-F0-9]{40}$",
                    "type": "string"
                  },
                  "value": {
                    "description": "Native value in wei, as an integer string.",
                    "maxLength": 78,
                    "pattern": "^(0|[1-9][0-9]*)$",
                    "type": "string"
                  }
                },
                "required": [
                  "chain",
                  "from",
                  "to",
                  "value",
                  "data"
                ],
                "type": "object"
              },
              "bodyType": {
                "enum": [
                  "json",
                  "form-data",
                  "text"
                ],
                "type": "string"
              },
              "method": {
                "enum": [
                  "POST",
                  "PUT",
                  "PATCH"
                ],
                "type": "string"
              },
              "type": {
                "const": "http",
                "type": "string"
              }
            },
            "required": [
              "type",
              "method",
              "bodyType",
              "body"
            ],
            "type": "object"
          }
        },
        "required": [
          "input"
        ],
        "type": "object"
      }
    }
  },
  "tags": [
    "transaction",
    "simulation",
    "security",
    "bazaar"
  ],
  "sourceHost": "mcp.dropenginehq.com",
  "lastUpdated": "2026-09-28T09:53:15.936Z",
  "quality": {
    "calls30d": 1,
    "uniquePayers30d": 1,
    "lastCalledAt": "2026-09-28T09:53:15.715Z"
  },
  "metadata": {
    "serviceName": "Transaction Preflight",
    "extensions": {
      "bazaar": {
        "info": {
          "input": {
            "body": {
              "chain": "base",
              "data": "0x",
              "from": "0x1111111111111111111111111111111111111111",
              "to": "0x1111111111111111111111111111111111111111",
              "value": "0"
            },
            "bodyType": "json",
            "method": "POST",
            "type": "http"
          }
        },
        "schema": {
          "$schema": "https://json-schema.org/draft/2020-12/schema",
          "properties": {
            "input": {
              "additionalProperties": false,
              "properties": {
                "body": {
                  "additionalProperties": false,
                  "properties": {
                    "chain": {
                      "description": "Base mainnet, or Base Sepolia for test transactions.",
                      "enum": [
                        "base",
                        "base-sepolia"
                      ],
                      "type": "string"
                    },
                    "data": {
                      "description": "Unsigned transaction calldata; no signing material.",
                      "maxLength": 131074,
                      "pattern": "^0x([a-fA-F0-9]{2})*$",
                      "type": "string"
                    },
                    "from": {
                      "pattern": "^0x[a-fA-F0-9]{40}$",
                      "type": "string"
                    },
                    "to": {
                      "pattern": "^0x[a-fA-F0-9]{40}$",
                      "type": "string"
                    },
                    "value": {
                      "description": "Native value in wei, as an integer string.",
                      "maxLength": 78,
                      "pattern": "^(0|[1-9][0-9]*)$",
                      "type": "string"
                    }
                  },
                  "required": [
                    "chain",
                    "from",
                    "to",
                    "value",
                    "data"
                  ],
                  "type": "object"
                },
                "bodyType": {
                  "enum": [
                    "json",
                    "form-data",
                    "text"
                  ],
                  "type": "string"
                },
                "method": {
                  "enum": [
                    "POST",
                    "PUT",
                    "PATCH"
                  ],
                  "type": "string"
                },
                "type": {
                  "const": "http",
                  "type": "string"
                }
              },
              "required": [
                "type",
                "method",
                "bodyType",
                "body"
              ],
              "type": "object"
            }
          },
          "required": [
            "input"
          ],
          "type": "object"
        }
      }
    }
  },
  "liveness": {
    "reliability": null
  },
  "verified": false,
  "featured": false,
  "provider": {
    "host": "mcp.dropenginehq.com",
    "manifest_name": "mcp.dropenginehq.com",
    "source": "cdp-mirror",
    "source_manifest_url": "https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources",
    "submitted_at": "2026-10-14T01:15:01.050Z"
  }
}