diff --git a/src/Api.php b/src/Api.php
index 376aa92..77b4435 100644
--- a/src/Api.php
+++ b/src/Api.php
@@ -126,14 +126,6 @@ class Api
         $consumer_key = null,
         Client $http_client = null
     ) {
-        if (!isset($application_key)) {
-            throw new Exceptions\InvalidParameterException("Application key parameter is empty");
-        }
-
-        if (!isset($application_secret)) {
-            throw new Exceptions\InvalidParameterException("Application secret parameter is empty");
-        }
-
         if (!isset($api_endpoint)) {
             throw new Exceptions\InvalidParameterException("Endpoint parameter is empty");
         }
@@ -236,6 +228,17 @@ class Api
      */
     protected function rawCall($method, $path, $content = null, $is_authenticated = true, $headers = null)
     {
+        if ( $is_authenticated )
+        {
+            if (!isset($this->application_key)) {
+                throw new Exceptions\InvalidParameterException("Application key parameter is empty");
+            }
+
+            if (!isset($this->application_secret)) {
+                throw new Exceptions\InvalidParameterException("Application secret parameter is empty");
+            }
+        }
+
         $url     = $this->endpoint . $path;
         $request = new Request($method, $url);
         if (isset($content) && $method == 'GET') {
@@ -278,9 +281,11 @@ class Api
             $headers = [];
         }
         $headers['Content-Type']      = 'application/json; charset=utf-8';
-        $headers['X-Ovh-Application'] = $this->application_key;
 
         if ($is_authenticated) {
+
+            $headers['X-Ovh-Application'] = $this->application_key;
+
             if (!isset($this->time_delta)) {
                 $this->calculateTimeDelta();
             }
@@ -318,15 +323,27 @@ class Api
      *
      * @param string $path    path ask inside api
      * @param array  $content content to send inside body of request
+     * @param array  headers  custom HTTP headers to add on the request
+     * @param bool   is_authenticated   if the request need to be authenticated
      *
      * @return array
      * @throws \GuzzleHttp\Exception\ClientException if http request is an error
      */
-    public function get($path, $content = null, $headers = null)
+    public function get($path, $content = null, $headers = null, $is_authenticated = true)
     {
-        return $this->decodeResponse(
-            $this->rawCall("GET", $path, $content, true, $headers)
-        );
+        if(preg_match('/^\/[^\/]+\.json$/', $path))
+        {
+          // Schema description must be access without authentication
+          return $this->decodeResponse(
+              $this->rawCall("GET", $path, $content, false, $headers)
+          );
+        }
+        else
+        {
+          return $this->decodeResponse(
+              $this->rawCall("GET", $path, $content, $is_authenticated, $headers)
+          );
+        }
     }
 
     /**
@@ -334,14 +351,16 @@ class Api
      *
      * @param string $path    path ask inside api
      * @param array  $content content to send inside body of request
+     * @param array  headers  custom HTTP headers to add on the request
+     * @param bool   is_authenticated   if the request need to be authenticated
      *
      * @return array
      * @throws \GuzzleHttp\Exception\ClientException if http request is an error
      */
-    public function post($path, $content = null, $headers = null)
+    public function post($path, $content = null, $headers = null, $is_authenticated = true)
     {
         return $this->decodeResponse(
-            $this->rawCall("POST", $path, $content, true, $headers)
+            $this->rawCall("POST", $path, $content, $is_authenticated, $headers)
         );
     }
 
@@ -350,14 +369,16 @@ class Api
      *
      * @param string $path    path ask inside api
      * @param array  $content content to send inside body of request
+     * @param array  headers  custom HTTP headers to add on the request
+     * @param bool   is_authenticated   if the request need to be authenticated
      *
      * @return array
      * @throws \GuzzleHttp\Exception\ClientException if http request is an error
      */
-    public function put($path, $content, $headers = null)
+    public function put($path, $content, $headers = null, $is_authenticated = true)
     {
         return $this->decodeResponse(
-            $this->rawCall("PUT", $path, $content, true, $headers)
+            $this->rawCall("PUT", $path, $content, $is_authenticated, $headers)
         );
     }
 
@@ -366,14 +387,16 @@ class Api
      *
      * @param string $path    path ask inside api
      * @param array  $content content to send inside body of request
+     * @param array  headers  custom HTTP headers to add on the request
+     * @param bool   is_authenticated   if the request need to be authenticated
      *
      * @return array
      * @throws \GuzzleHttp\Exception\ClientException if http request is an error
      */
-    public function delete($path, $content = null, $headers = null)
+    public function delete($path, $content = null, $headers = null, $is_authenticated = true)
     {
         return $this->decodeResponse(
-            $this->rawCall("DELETE", $path, $content, true, $headers)
+            $this->rawCall("DELETE", $path, $content, $is_authenticated, $headers)
         );
     }
 
diff --git a/tests/ApiFunctionalTest.php b/tests/ApiFunctionalTest.php
index a1b9883..59d3954 100644
--- a/tests/ApiFunctionalTest.php
+++ b/tests/ApiFunctionalTest.php
@@ -250,4 +250,13 @@ class ApiFunctionalTest extends \PHPUnit_Framework_TestCase
     {
         $this->api->get('/me/api/credential', ['status' => 'pendingValidation']);
     }
+
+    /**
+     * Test APi::get without authentication
+     */
+    public function testApiGetWithoutAuthentication()
+    {
+        $api = new Api(NULL,NULL, $this->endpoint, null, $this->client);
+        $api->get('/hosting/web/moduleList',null,null,false);
+    }
 }
diff --git a/tests/ApiTest.php b/tests/ApiTest.php
index fdb464e..e9790b8 100644
--- a/tests/ApiTest.php
+++ b/tests/ApiTest.php
@@ -117,7 +117,8 @@ class ApiTest extends \PHPUnit_Framework_TestCase
     public function testMissingApplicationKey()
     {
         $this->setExpectedException('\\Ovh\\Exceptions\\InvalidParameterException', 'Application key');
-        new Api(null, $this->application_secret, $this->endpoint, $this->consumer_key, $this->client);
+        $api = new Api(null, $this->application_secret, $this->endpoint, $this->consumer_key, $this->client);
+        $api->get('/me');
     }
 
     /**
@@ -126,7 +127,29 @@ class ApiTest extends \PHPUnit_Framework_TestCase
     public function testMissingApplicationSecret()
     {
         $this->setExpectedException('\\Ovh\\Exceptions\\InvalidParameterException', 'Application secret');
-        new Api($this->application_key, null, $this->endpoint, $this->consumer_key, $this->client);
+        $api = new Api($this->application_key, null, $this->endpoint, $this->consumer_key, $this->client);
+        $api->get('/me');
+    }
+
+    /**
+     * Test we don't check Application Key for unauthenticated call
+     */
+    public function testNoCheckAppKeyForUnauthCall()
+    {
+        $handlerStack = $this->client->getConfig('handler');
+        $handlerStack->push(Middleware::mapRequest(function (Request $request) {
+            if($request->getUri()->getPath() == "/1.0/unauthcall") {
+                return $request;
+            }
+
+            $request = $request->withUri($request->getUri()
+                ->withHost('httpbin.org')
+                ->withPath('/')
+                ->withQuery(''));
+            return $request;
+        }));
+        $api = new Api(NULL, NULL, $this->endpoint, $this->consumer_key, $this->client);
+        $api->get('/1.0/unauthcall', null, null, false);
     }
 
     /**