Anybody knows the cause of this error

{
   type: "error.SuiteScriptModuleLoaderError",
   name: "UNEXPECTED_ERROR",
   message: "",
   "stack": []
}

? It intermittent and when I reload the suitelet once or twice it disappears.

Look for duplicate copies of one or more of your SuiteScript files in your file cabinet. That error looks to me like it cannot find the file it wants in the folder you are executing from.

So this could be the ones I specify in the form.clientModulePath, right