{
    "$schema": "http://json-schema.org/draft-04/schema#",
    "type": "array",
    "items": {
        "type": "object",
        "properties": {
            "id": {
                "type": "number"
            },
            "name": {
                "type": "string"
            },
            "description": {
                "type": "string"
            },
            "build_time": {
                "type": "number"
            },
            "icon": {
                "type": "string"
            },
            "type": {
                "type": "string"
            },
            "required_level": {
                "type": "number"
            },
            "experience": {
                "type": "number"
            },
            "prerequisites": {
                "type": "array",
                "items": {}
            },
            "costs": {
                "type": "array",
                "items": {
                    "type": "object",
                    "properties": {
                        "type": {
                            "type": "string"
                        },
                        "count": {
                            "type": "number"
                        },
                        "name": {
                            "type": "string"
                        },
                        "item_id": {
                            "type": "number"
                        }
                    }
                }
            }
        },
        "required": [
            "id",
            "name",
            "description",
            "build_time",
            "icon",
            "type",
            "required_level",
            "experience",
            "prerequisites",
            "costs"
        ]
    },
    "properties": {},
    "additionalProperties": false
}