diff --git a/README.md b/README.md
index 0f139e2..f177849 100644
--- a/README.md
+++ b/README.md
@@ -21,4 +21,7 @@ Now it is only one adapter ``GoogleTranslatorAdapter`` which uses [stichoza/goog
 ```yaml
     App\Service\Translator\AdapterInterface:
         class: App\Service\Translator\Adapter\GoogleTranslatorAdapter
-```
\ No newline at end of file
+```
+
+## REST API
+To explore API documentation you could copy [open-api.yaml](docs/open-api.yaml) content to https://editor.swagger.io/
\ No newline at end of file
diff --git a/config/routes/dev/framework.yaml b/config/routes/dev/framework.yaml
deleted file mode 100644
index bcbbf13..0000000
--- a/config/routes/dev/framework.yaml
+++ /dev/null
@@ -1,3 +0,0 @@
-_errors:
-    resource: '@FrameworkBundle/Resources/config/routing/errors.xml'
-    prefix: /_error
diff --git a/docs/open-api.yaml b/docs/open-api.yaml
new file mode 100644
index 0000000..d2aa10e
--- /dev/null
+++ b/docs/open-api.yaml
@@ -0,0 +1,67 @@
+openapi: 3.0.1
+info:
+    title: Assessment API
+    description: 'Assessment API'
+    version: v1
+
+paths:
+    /questions:
+        get:
+            summary: Returns the list of translated questions and associated choices
+            parameters:
+              - in: query
+                required: true
+                name: lang
+                schema:
+                  type: string
+                description: Language (ISO-639-1 code) in which the questions and choices should be translated
+            responses:
+                200:
+                    description: List of translated questions and associated choices
+                    content:
+                      application/json:
+                        schema:
+                          $ref: '#/components/schemas/QuestionList'
+        post:
+            summary: Creates a new question and associated choices (the number of associated choices must be exactly equal to 3)
+            requestBody:
+              required: true
+              content:
+                application/json:
+                  schema:
+                    $ref: '#/components/schemas/Question'
+            responses:
+                200:
+                    description: Question and associated choices (not translated)
+                    content:
+                      application/json:
+                        schema:
+                          $ref: '#/components/schemas/Question'
+components:
+    schemas:
+        QuestionList:
+            type: object
+            properties:
+                data:
+                    type: array
+                    items:
+                      $ref: '#/components/schemas/Question'
+        Question:
+            type: object
+            properties:
+                text:
+                    type: string
+                createdAt:
+                    type: string
+                    format: date-time
+                    description: Creation date of the question
+                choices:
+                    type: array
+                    description: Choices associated to the question
+                    items:
+                      $ref: '#/components/schemas/Choice'
+        Choice:
+            type: object
+            properties:
+                text:
+                    type: string
\ No newline at end of file
diff --git a/src/Domain/Service/API/DTO/MultipleChoiceQuestionDTO.php b/src/Domain/Service/API/DTO/MultipleChoiceQuestionDTO.php
index d18c130..aa5e395 100644
--- a/src/Domain/Service/API/DTO/MultipleChoiceQuestionDTO.php
+++ b/src/Domain/Service/API/DTO/MultipleChoiceQuestionDTO.php
@@ -40,6 +40,7 @@ public static function fromPSRRequest(RequestInterface $request)
             throw new APIValidationException('Request does not contain valid JSON object');
         }
 
+        // Todo check datetime and format for createdAt
         foreach (static::REQUIRED_PROPS as $propName) {
             if (!isset($data[$propName])) {
                 throw new APIValidationException(sprintf(static::MISSED_PROPERTY_ERROR_MESSAGE_TEMPLATE, $propName));
diff --git a/tests/Integration/.gitkeep b/tests/Integration/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/tests/Unit/.gitkeep b/tests/Unit/.gitkeep
new file mode 100644
index 0000000..e69de29