chore: Improved README

Author: 4drian3d

README.md

@@ -1,2 +1,24 @@
-# Example-Expansion
-Example Expansion for MiniPlaceholders
+# PlaceholderAPI-Expansion
+PlaceholderAPI Expansion for MiniPlaceholders
+
+## Supported Platforms
+
+- Paper
+- Folia
+
+## Placeholders
+
+- `<placeholderapi_global:(placeholder)>`
+
+This placeholder does not require any player to work.
+Its operation would be similar to running the command `/papi parse --null (placeholders)`
+
+- `<placeholderapi_player:(placeholder)>`
+
+This placeholder requires an online player to function.
+Its operation would be similar to running the `/papi parse me (placeholders)` command
+
+- `<placeholderapi_relational:(placeholder)>`
+
+This placeholder requires two online players to work.
+The functioning of this placeholder depends on whether the plugin in which it is used has relational placeholder support