Is SublimeLinter giving me the correct errors?

I'm using Sublimetext 3 and SublimeLinter (along with SublimeLinter-php) to lint my files. I've never used this plugin before (nor have I used IDE's extensively in PHP) and I'm seeing SublimeLinter show errors like this in my code: (some laravel code)

These are the errors I'm getting for each of those lines:

11: undeclared parent class Controller
12: undefined identifier 'Request'
14: unknown class Post
19: unresolved function response

Are these actual errors that SublimeLinter should have picked up? Or is my configuration for SublimeLinter wrong which is causing it to pick up these lines as errors by mistake?

Solution

Turns out this was happening because I did not have a sublime project set up.

A project can be set up my clicking Project > Save Project As... from the project menu drop down