schema.json

{
    "$ref": "#/definitions/MyObject",
    "$schema": "http://json-schema.org/draft-07/schema#",
    "definitions": {
        "MyGeneric<number,string>": {
            "additionalProperties": false,
            "properties": {
                "field": {
                    "$ref": "#/definitions/MyGeneric<string,number>"
                }
            },
            "required": [
                "field"
            ],
            "type": "object"
        },
        "MyGeneric<string,number>": {
            "additionalProperties": false,
            "properties": {
                "field": {
                    "$ref": "#/definitions/MyGeneric<number,string>"
                }
            },
            "required": [
                "field"
            ],
            "type": "object"
        },
        "MyObject": {
            "additionalProperties": false,
            "properties": {
                "value": {
                    "$ref": "#/definitions/MyGeneric<string,number>"
                }
            },
            "required": [
                "value"
            ],
            "type": "object"
        }
    }
}