espocrm/schema/metadata/app/clientIcons.json

{
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "$id": "https://www.espocrm.com/schema/metadata/app/clientIcons.json",
    "title": "app/icons",
    "description": "Client icons.",
    "type": "object",
    "properties": {
        "classList": {
            "description": "Icon classes.",
            "type": "array",
            "items": {
                "anyOf": [
                    {"type": "string"},
                    {"enum": ["__APPEND__"]}
                ]
            }
        }
    }
}