{
  "x402Version": 2,
  "id": 6803,
  "slug": "6803",
  "resource": "https://api.agentmercantile.com/v1/transaction-gas-preflight",
  "description": "Return bounded factual eth_estimateGas units and recent eth_feeHistory execution-fee evidence for one unsigned Ethereum or Base transaction. Not execution, signing, custody, trading, or a guaranteed final cost. Call when you need point-in-time gas units and recent execution-fee context before signing or submitting.",
  "type": "http",
  "accepts": [
    {
      "scheme": "exact",
      "network": "eip155:8453",
      "payTo": "0xdb7b2b54f80479826222749a2ea73a8acc306e1e",
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "amount": "5000",
      "maxTimeoutSeconds": 60
    }
  ],
  "outputSchema": {
    "bazaar": {
      "info": {
        "description": "Return bounded factual eth_estimateGas units and recent eth_feeHistory execution-fee evidence for one unsigned Ethereum or Base transaction. Not execution, signing, custody, trading, or a guaranteed final cost. Call when you need point-in-time gas units and recent execution-fee context before signing or submitting.",
        "input": {
          "body": {
            "chain": "eip155:8453",
            "data": "0x",
            "to": "0x0000000000000000000000000000000000000001",
            "value_wei": "0"
          },
          "bodyType": "json",
          "method": "POST",
          "type": "http"
        },
        "output": {
          "example": {
            "chain": {
              "caip2": "eip155:8453",
              "chain_id": 8453,
              "name": "base"
            },
            "fee_history": {
              "block_count": 5,
              "newest_block": "latest"
            },
            "gas_estimate": {
              "gas_units": "21000"
            },
            "illustrative_execution_fees": {
              "covers": "l2_execution_fee_only",
              "guaranteed_final_cost": false,
              "kind": "illustrative_execution_fee_observations",
              "recommendation": false
            },
            "limitations": [
              "Point-in-time gas evidence, not a guaranteed final cost or total transaction cost."
            ],
            "machine": "VM06",
            "methodology_version": "transaction-gas-preflight-0.1.0",
            "request_shape": {
              "calldata_bytes": 0,
              "has_from": false,
              "value_nonzero": false
            },
            "status": "OK"
          },
          "type": "json"
        }
      },
      "schema": {
        "$schema": "https://json-schema.org/draft/2020-12/schema",
        "properties": {
          "input": {
            "additionalProperties": false,
            "properties": {
              "body": {
                "additionalProperties": false,
                "properties": {
                  "chain": {
                    "description": "Analysis chain only. Payment remains Base eip155:8453.",
                    "enum": [
                      "eip155:1",
                      "eip155:8453"
                    ],
                    "type": "string"
                  },
                  "data": {
                    "description": "Optional 0x-prefixed even-length hex calldata. Default 0x. Maximum 8192 bytes. Request body maximum 20480 bytes.",
                    "maxLength": 16386,
                    "pattern": "^0x(?:[0-9a-fA-F]{2})*$",
                    "type": "string"
                  },
                  "from": {
                    "description": "Optional 0x-prefixed 20-byte sender used only as an eth_estimateGas field. No ownership is implied.",
                    "pattern": "^0x[0-9a-fA-F]{40}$",
                    "type": "string"
                  },
                  "to": {
                    "description": "Required 0x-prefixed 20-byte destination. Contract creation is not supported.",
                    "pattern": "^0x[0-9a-fA-F]{40}$",
                    "type": "string"
                  },
                  "value_wei": {
                    "description": "Optional unsigned base-10 integer string in the uint256 range. Default 0. JSON Schema cannot express the full uint256 upper bound; runtime validation rejects values above 2^256-1.",
                    "pattern": "^(0|[1-9][0-9]*)$",
                    "type": "string"
                  }
                },
                "required": [
                  "chain",
                  "to"
                ],
                "type": "object"
              },
              "bodyType": {
                "enum": [
                  "json",
                  "form-data",
                  "text"
                ],
                "type": "string"
              },
              "method": {
                "enum": [
                  "POST"
                ],
                "type": "string"
              },
              "type": {
                "const": "http",
                "type": "string"
              }
            },
            "required": [
              "type",
              "method",
              "bodyType",
              "body"
            ],
            "type": "object"
          },
          "output": {
            "properties": {
              "example": {
                "additionalProperties": true,
                "properties": {
                  "chain": {
                    "type": "object"
                  },
                  "fee_history": {
                    "description": "Recent eth_feeHistory execution-fee evidence.",
                    "type": [
                      "object",
                      "null"
                    ]
                  },
                  "gas_estimate": {
                    "description": "eth_estimateGas units when estimable.",
                    "type": [
                      "object",
                      "null"
                    ]
                  },
                  "illustrative_execution_fees": {
                    "description": "Illustrative L2 execution-fee observations, not a guaranteed final cost.",
                    "type": [
                      "object",
                      "null"
                    ]
                  },
                  "limitations": {
                    "items": {
                      "type": "string"
                    },
                    "type": "array"
                  },
                  "machine": {
                    "enum": [
                      "VM06"
                    ],
                    "type": "string"
                  },
                  "methodology_version": {
                    "enum": [
                      "transaction-gas-preflight-0.1.0"
                    ],
                    "type": "string"
                  },
                  "request_shape": {
                    "type": "object"
                  },
                  "status": {
                    "enum": [
                      "OK",
                      "PARTIAL",
                      "UNESTIMABLE",
                      "HOLD"
                    ],
                    "type": "string"
                  }
                },
                "required": [
                  "status",
                  "machine",
                  "methodology_version",
                  "chain",
                  "gas_estimate",
                  "limitations"
                ],
                "type": "object"
              },
              "type": {
                "type": "string"
              }
            },
            "required": [
              "type"
            ],
            "type": "object"
          }
        },
        "required": [
          "input"
        ],
        "type": "object"
      }
    }
  },
  "tags": [
    "bazaar"
  ],
  "sourceHost": "api.agentmercantile.com",
  "lastUpdated": "2026-09-17T03:59:00.452Z",
  "quality": {
    "calls30d": 2,
    "uniquePayers30d": 2,
    "lastCalledAt": "2026-09-17T03:59:00.125Z"
  },
  "liveness": {},
  "verified": false,
  "featured": false,
  "provider": {
    "host": "api.agentmercantile.com",
    "manifest_name": "api.agentmercantile.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"
  }
}