{
  "x402Version": 2,
  "id": 6896,
  "slug": "6896",
  "resource": "https://api.nexismvp.com/market/gas-preflight",
  "description": "Simulate a Base mainnet transaction before submitting it — real eth_estimateGas + eth_call against the given {to, data, value}, returns whether it would succeed, estimated gas, and estimated cost. POST body required. Experimental/informational only — not financial advice.",
  "type": "http",
  "accepts": [
    {
      "scheme": "exact",
      "network": "eip155:8453",
      "payTo": "0x3B59f268EbC38c5F43B8B9bE37238bf43378Ad87",
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "amount": "1000",
      "maxTimeoutSeconds": 300
    }
  ],
  "outputSchema": {
    "bazaar": {
      "info": {
        "input": {
          "body": {
            "chain": "base",
            "data": "0x",
            "to": "0x3B59f268EbC38c5F43B8B9bE37238bf43378Ad87",
            "value": "0x0"
          },
          "bodyType": "json",
          "method": "POST",
          "type": "http"
        },
        "output": {
          "example": {
            "estimated_cost_eth": 1e-7,
            "estimated_gas": 21000,
            "revert_reason": null,
            "will_succeed": true
          },
          "type": "json"
        }
      },
      "schema": {
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "properties": {
          "input": {
            "additionalProperties": false,
            "properties": {
              "body": {
                "properties": {
                  "chain": {
                    "description": "Only 'base' supported currently",
                    "enum": [
                      "base"
                    ],
                    "type": "string"
                  },
                  "data": {
                    "description": "Call data, 0x-prefixed hex (default 0x)",
                    "type": "string"
                  },
                  "to": {
                    "description": "Target address",
                    "type": "string"
                  },
                  "value": {
                    "description": "Value in wei, 0x-prefixed hex (default 0x0)",
                    "type": "string"
                  }
                },
                "required": [
                  "to"
                ],
                "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"
          },
          "output": {
            "properties": {
              "example": {
                "properties": {
                  "estimated_cost_eth": {
                    "type": "number"
                  },
                  "estimated_gas": {
                    "type": "integer"
                  },
                  "revert_reason": {
                    "type": [
                      "string",
                      "null"
                    ]
                  },
                  "will_succeed": {
                    "type": "boolean"
                  }
                },
                "required": [
                  "will_succeed"
                ],
                "type": "object"
              },
              "type": {
                "type": "string"
              }
            },
            "required": [
              "type"
            ],
            "type": "object"
          }
        },
        "required": [
          "input"
        ],
        "type": "object"
      }
    }
  },
  "tags": [
    "bazaar"
  ],
  "sourceHost": "api.nexismvp.com",
  "lastUpdated": "2026-09-14T06:34:59.625Z",
  "quality": {
    "calls30d": 1,
    "uniquePayers30d": 1,
    "lastCalledAt": "2026-09-14T06:34:59.382Z"
  },
  "liveness": {},
  "verified": false,
  "featured": false,
  "provider": {
    "host": "api.nexismvp.com",
    "manifest_name": "api.nexismvp.com",
    "source": "cdp-mirror",
    "source_manifest_url": "https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources",
    "submitted_at": "2026-09-18T22:00:31.484Z"
  }
}