That path value itself appears correct. (The '\' characters would be to escape the '"' characters, but that may or may not be necessary depending on your client/environment.)
Getting the response body is the right way to begin debugging this. Exactly how you do so depends on the particular HTTP client you're using though, so I'm afraid I can't offer specific instructions if you're not using an official Dropbox SDK. You should refer to the documentation for your HTTP client for information on how to retrieve the response body.