Minor documentation tweaks

Author: peternewman

README.md

@@ -1,9 +1,18 @@
 # sort-problem-matcher
 
-This problem matcher lets you show errors from GNU `sort` as annotation in GitHub Actions.
+This problem matcher lets you show errors from GNU `sort -c` as annotation in
+GitHub Actions.
 
 Based on korelstar's xmllint-problem-matcher.
 
+## Inputs
+
+No inputs are required.
+
+## Outputs
+
+No outputs are generated apart from a configured problem matcher.
+
 ## Usage
 
 Add the step to your workflow, before `sort -c` is called.

action.yml

@@ -5,5 +5,5 @@ runs:
   using: 'node12'
   main: 'index.js'
 branding:
-  icon: 'check-square'
+  icon: 'search'
   color: 'green'