diff --git a/gatherling/api.php b/gatherling/api.php
index 27d107c2e..46bce18e8 100644
--- a/gatherling/api.php
+++ b/gatherling/api.php
@@ -157,10 +157,10 @@
         break;
 
     case 'whoami':
-        auth();
+        $auth_error = auth();
         $player = Player::getSessionPlayer();
         if (is_null($player)) {
-            error('Not Logged in', ['name' => null]);
+            error('Not Logged in', ['name' => null, 'auth_error' => $auth_error]);
         }
 
         $result = repr_json_player($player);
diff --git a/gatherling/api_lib.php b/gatherling/api_lib.php
index b81525c77..559a57316 100644
--- a/gatherling/api_lib.php
+++ b/gatherling/api_lib.php
@@ -45,7 +45,7 @@ function is_admin()
     return false;
 }
 
-/** @return bool  */
+/** @return string  */
 function auth()
 {
     $username = null;
@@ -60,16 +60,19 @@ function auth()
     }
 
     if (is_null($username) || is_null($apikey)) {
-        return false;
+        return "Auth not provided";
     }
 
     $player = Player::findByName($username);
     if (is_null($player)) {
-        return false;
+        return "Can't find a user called $username";
     }
     if ($player->api_key == $apikey) {
         $_SESSION['username'] = $player->name;
     }
+    else {
+        return "Invalid API Key";
+    }
 
     return Player::isLoggedIn();
 }