I really have no idea why it would create this weird entries, but you should not have to go to http://domain/public/develop/.... The public is too much, as far as I know.

What if you just go to

http://test.app/develop/building/5

?

hm, I thought I have to go to the public folder. Because the Route:: object always starts with public/

If there is a public in your url depends on your configuration. I have it on my local machine. That's not important.
I think it has to do something with the Session. There is no other way that "old" values stay remembered.
Don't use sessions to handle a temporary request, maybe it should be Input::get?
BTW, make your life simpler and use link_to_route() in your view.

I don't use Sessions. I just use the routes. Or do those routes use sessions?

I can't use link_to_route() because I need those links to be around <button> elements like this

<a>
<button></button>
</a>

Yes, the $building_id is passed directly, not using the Session.
I havo no other idea, sorry.
Diedump the SQL log for current request, maybe this will help you.

dd(DB::getQueryLog());

Just use my package :) https://github.com/xscence/Laravel-facebook-sdk-v4-lbook if you want ufc

hm, that's very strange. If I diedump this (I did it in App::after()) the script should stop working, am I right? Hence, every SQL query should be in this diedump. But I only have this:

  3 => 
    array (size=3)
      'query' => string 'insert into `actions` (`user_id`, `location_id`, `action_type_id`, `access_id`, `second_access_id`, `fire_time`, `visible`, `updated_at`, `created_at`) values (?, ?, ?, ?, ?, ?, ?, ?, ?)' (length=186)
      'bindings' => 
        array (size=9)
          0 => string '1' (length=1)
          1 => string '1' (length=1)
          2 => int 1
          3 => string '1' (length=1)
          4 => string '5' (length=1)
          5 => 
            object(Carbon\Carbon)[335]
              ...
          6 => int 1
          7 => string '2014-10-23 07:06:21' (length=19)
          8 => string '2014-10-23 07:06:21' (length=19)
      'time' => float 0.68

That's the correct one, with binding 4 => string '5'

That's what it created in my database: The last row is the correct one.

I have absolutely no clue where the error is :/

PS: The Facebook sdk => Do you mean the "API calls"? But I don't know, if I need this.

Found a question on Stackoverflow that might discuss the same problem: http://stackoverflow.com/questions/23422703/laravel-4-routes-with-parameters-gets-called-twice/23500953#23500953

Unfortunately, the person who answered it, didn't exactly write how to solve it :/

but maybe it helps someone to find the problem. I have no idea what I can do :(