Road User Tools Agent & API Platform

Convert fuel economy

Convert between UK MPG, US MPG, litres per 100 kilometres, and kilometres per litre.

Interfaces

POST

REST endpoint/api/v1/fuel-economy/convert

MCP

Tool nameconvert_fuel_economy

Request

Send the request as JSON. MCP clients pass the same fields as tool arguments.

cURLshell

curl -X POST https://roaduser.tools/api/v1/fuel-economy/convert \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "content-type: application/json" \
  -d '{
  "value": 40,
  "from": "mpg_uk",
  "to": "l_per_100km"
}'

Request bodyjson

{
  "value": 40,
  "from": "mpg_uk",
  "to": "l_per_100km"
}

Response

REST wraps the calculation result in the standard success envelope. MCP returns the same calculation data as structured tool output.

JSON

{
  "ok": true,
  "data": {
    "input": {
      "value": 40,
      "from": "mpg_uk",
      "to": "l_per_100km"
    },
    "conversions": {
      "mpg_uk": 40,
      "mpg_us": 33.30696738515955,
      "l_per_100km": 7.062023408295555,
      "km_per_l": 14.160247597385885
    },
    "result": 7.062023408295555
  }
}

{
  "ok": false,
  "error": {
    "code": "invalid_request",
    "message": "Invalid request input."
  }
}

Schemas

The definitions below show the complete JSON Schema used to validate inputs and describe outputs.

Input schema

{
  "type": "object",
  "additionalProperties": false,
  "properties": {
    "value": {
      "type": "number",
      "description": "Fuel economy value to convert. Must be finite and greater than zero."
    },
    "from": {
      "type": "string",
      "enum": [
        "mpg_uk",
        "mpg_us",
        "l_per_100km",
        "km_per_l"
      ],
      "description": "Input fuel economy unit."
    },
    "to": {
      "type": "string",
      "enum": [
        "mpg_uk",
        "mpg_us",
        "l_per_100km",
        "km_per_l"
      ],
      "description": "Optional target unit. When omitted, all units are returned."
    }
  },
  "required": [
    "value",
    "from"
  ]
}

Output schema

{
  "type": "object",
  "additionalProperties": false,
  "properties": {
    "input": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "value": {
          "type": "number"
        },
        "from": {
          "type": "string",
          "enum": [
            "mpg_uk",
            "mpg_us",
            "l_per_100km",
            "km_per_l"
          ]
        },
        "to": {
          "type": "string",
          "enum": [
            "mpg_uk",
            "mpg_us",
            "l_per_100km",
            "km_per_l"
          ]
        }
      },
      "required": [
        "value",
        "from"
      ]
    },
    "conversions": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "mpg_uk": {
          "type": "number"
        },
        "mpg_us": {
          "type": "number"
        },
        "l_per_100km": {
          "type": "number"
        },
        "km_per_l": {
          "type": "number"
        }
      },
      "required": [
        "mpg_uk",
        "mpg_us",
        "l_per_100km",
        "km_per_l"
      ]
    },
    "result": {
      "type": "number",
      "description": "Target-unit result when a target unit is supplied."
    }
  },
  "required": [
    "input",
    "conversions"
  ]
}