diff --git a/app/Api/V1/Controllers/AboutController.php b/app/Api/V1/Controllers/AboutController.php
index 77e63b7c64..2f7795d05c 100644
--- a/app/Api/V1/Controllers/AboutController.php
+++ b/app/Api/V1/Controllers/AboutController.php
@@ -26,20 +26,25 @@ namespace FireflyIII\Api\V1\Controllers;
 
 use DB;
 use FireflyIII\Transformers\UserTransformer;
+use Illuminate\Http\JsonResponse;
 use Illuminate\Http\Request;
 use League\Fractal\Manager;
 use League\Fractal\Resource\Item;
 use League\Fractal\Serializer\JsonApiSerializer;
 
 /**
+ * Returns basic information about this installation.
+ *
  * Class AboutController
  */
 class AboutController extends Controller
 {
     /**
-     * @return \Illuminate\Http\JsonResponse
+     * Returns system information.
+     *
+     * @return JsonResponse
      */
-    public function about()
+    public function about(): JsonResponse
     {
         $search        = ['~', '#'];
         $replace       = ['\~', '# '];
@@ -59,11 +64,13 @@ class AboutController extends Controller
     }
 
     /**
+     * Returns information about the user.
+     *
      * @param Request $request
      *
-     * @return \Illuminate\Http\JsonResponse
+     * @return JsonResponse
      */
-    public function user(Request $request)
+    public function user(Request $request): JsonResponse
     {
         $manager = new Manager();
         $baseUrl = $request->getSchemeAndHttpHost() . '/api/v1';
diff --git a/app/Api/V1/Controllers/AccountController.php b/app/Api/V1/Controllers/AccountController.php
index d20a6a2eb2..d5e0d4d255 100644
--- a/app/Api/V1/Controllers/AccountController.php
+++ b/app/Api/V1/Controllers/AccountController.php
@@ -30,6 +30,7 @@ use FireflyIII\Models\AccountType;
 use FireflyIII\Repositories\Account\AccountRepositoryInterface;
 use FireflyIII\Repositories\Currency\CurrencyRepositoryInterface;
 use FireflyIII\Transformers\AccountTransformer;
+use Illuminate\Http\JsonResponse;
 use Illuminate\Http\Request;
 use Illuminate\Pagination\LengthAwarePaginator;
 use League\Fractal\Manager;
@@ -50,8 +51,6 @@ class AccountController extends Controller
 
     /**
      * AccountController constructor.
-     *
-     * @throws \FireflyIII\Exceptions\FireflyException
      */
     public function __construct()
     {
@@ -75,9 +74,9 @@ class AccountController extends Controller
      *
      * @param \FireflyIII\Models\Account $account
      *
-     * @return \Illuminate\Http\Response
+     * @return JsonResponse
      */
-    public function delete(Account $account)
+    public function delete(Account $account): JsonResponse
     {
         $this->repository->destroy($account, null);
 
@@ -89,9 +88,9 @@ class AccountController extends Controller
      *
      * @param Request $request
      *
-     * @return \Illuminate\Http\JsonResponse
+     * @return JsonResponse
      */
-    public function index(Request $request)
+    public function index(Request $request): JsonResponse
     {
         // create some objects:
         $manager = new Manager();
@@ -128,7 +127,7 @@ class AccountController extends Controller
      *
      * @return \Illuminate\Http\JsonResponse
      */
-    public function show(Request $request, Account $account)
+    public function show(Request $request, Account $account): JsonResponse
     {
         $manager = new Manager();
 
@@ -148,7 +147,7 @@ class AccountController extends Controller
      *
      * @return \Illuminate\Http\JsonResponse
      */
-    public function store(AccountRequest $request)
+    public function store(AccountRequest $request): JsonResponse
     {
         $data = $request->getAll();
         // if currency ID is 0, find the currency by the code:
@@ -174,7 +173,7 @@ class AccountController extends Controller
      *
      * @return \Illuminate\Http\JsonResponse
      */
-    public function update(AccountRequest $request, Account $account)
+    public function update(AccountRequest $request, Account $account): JsonResponse
     {
         $data = $request->getAll();
         // if currency ID is 0, find the currency by the code:
diff --git a/app/Api/V1/Controllers/BillController.php b/app/Api/V1/Controllers/BillController.php
index de370ef3e3..c06b060df9 100644
--- a/app/Api/V1/Controllers/BillController.php
+++ b/app/Api/V1/Controllers/BillController.php
@@ -48,8 +48,6 @@ class BillController extends Controller
 
     /**
      * BillController constructor.
-     *
-     * @throws FireflyException
      */
     public function __construct()
     {
diff --git a/app/Api/V1/Controllers/TransactionController.php b/app/Api/V1/Controllers/TransactionController.php
index 18cdb56a7b..b877ab0c17 100644
--- a/app/Api/V1/Controllers/TransactionController.php
+++ b/app/Api/V1/Controllers/TransactionController.php
@@ -135,17 +135,19 @@ class TransactionController extends Controller
     /**
      * @param Request     $request
      * @param Transaction $transaction
+     * @param string      $include
      *
      * @return \Illuminate\Http\JsonResponse
      */
-    public function show(Request $request, Transaction $transaction)
+    public function show(Request $request, Transaction $transaction, string $include)
     {
         $manager = new Manager();
         $baseUrl = $request->getSchemeAndHttpHost() . '/api/v1';
         $manager->setSerializer(new JsonApiSerializer($baseUrl));
 
         // add include parameter:
-        $include = $request->get('include') ?? '';
+        $include = $include ?? '';
+        $include = $request->get('include') ?? $include;
         $manager->parseIncludes($include);
 
         // collect transactions using the journal collector