diff --git a/src/ReC.Domain/Constants/ApiKeyLocation.cs b/src/ReC.Domain/Constants/ApiKeyLocation.cs
new file mode 100644
index 0000000..fe6433b
--- /dev/null
+++ b/src/ReC.Domain/Constants/ApiKeyLocation.cs
@@ -0,0 +1,7 @@
+namespace ReC.Domain.Constants;
+
+public enum ApiKeyLocation
+{
+    Header = 0,
+    Query = 1
+}