`JsonRpcRequest` allows non-JSON values

[legobeat]

The resulting type of JsonRpcRequest:

export declare const JsonRpcRequestStruct: Struct<{
    id: string | number | null;
    method: string;
    jsonrpc: "2.0";
    params?: Json[] | Record<string, Json> | undefined;
}, {
    id: Struct<string | number | null, null>;
    jsonrpc: Struct<"2.0", "2.0">;
    method: Struct<string, null>;
    params: Struct<Json[] | Record<string, Json> | undefined, null>;
}>;


export declare type JsonRpcRequest<Params extends JsonRpcParams = JsonRpcParams> = InferWithParams<typeof JsonRpcRequestStruct, Params>;

This allows explicit undefined value for params, which is invalid JSON since undefined is not a valid JSON value. params?: Json[] | Record<string, Json> | undefined; should be params?: Json[] | Record<string, Json>;.

It seems like superstruct-derived optional always get a | undefined, which makes the resolution less obvious to me.