schema.json

{
    "$schema": "http://json-schema.org/draftv4/schema#",
    "type": "object",
    "required": [ "name", "mods" ],
    "additionalProperties": false,
    "properties": {
        "name": { "type": "string", "minLength": 1 },
        "mods": {
            "type": "array",
            "minItems": 1,
            "uniqueItems": true,
            "items": { "$ref": "#/definitions/mod" }
        }
    },
    "definitions": {
        "mod": {
            "type": "object",
            "required": [ "modfolder", "modfiles" ],
            "additionalProperties": false,
            "properties": {
                "modfolder": { "type": "string", "minLength": 1 },
                "modfiles": {
                    "type": "array",
                    "minItems": 1,
                    "items": { "$ref": "#/definitions/modfile" },
                    "uniqueItems": true
                }
            }
        },
        "modfile": {
            "type": "object",
            "required": [ "url", "localpath", "size", "sizecompressed", "checksum" ],
            "additionalProperties": false,
            "properties": {
                "url": { "type": "string", "format": "uri" },
                "localpath": { "type": "string", "pattern": "^[^/]+(/[^/]+)+" },
                "size": { "type": "integer", "minimum": 1 },
                "sizecompressed": { "type": "integer", "minimum": 1 },
                "checksum": { "type": "string", "format": "md5" }
            }
        }
    }
}