diff --git a/Composer-plugin.md b/Composer-plugin.md
index 14edbc7..5a62b4c 100644
--- a/Composer-plugin.md
+++ b/Composer-plugin.md
@@ -2,9 +2,9 @@ Allows you to run Composer within your build, to install dependencies prior to t
 
 ## Configuration
 ### Options
-* **directory** [optional] - Directory within which you want Composer to run (default: build root) 
-* **action** [optional - Action you wish Composer to run (default: 'install')
-* **prefer_dist** [optional - true|false whether Composer should run with the `--prefer-dist` flag (default: false)
+* **directory** [optional, string] - Directory within which you want Composer to run (default: build root) 
+* **action** [optional, string, update|install] - Action you wish Composer to run (default: 'install')
+* **prefer_dist** [optional, bool, true|false] - whether Composer should run with the `--prefer-dist` flag (default: false)
 
 ### Example
 ```yml