Update README.md

Author: David Kale

README.md

@@ -88,9 +88,19 @@ jobs:
   triage:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/labeler@v2
+    - uses: actions/labeler@main
       with:
         repo-token: "${{ secrets.GITHUB_TOKEN }}"
 ```
 
 _Note: This grants access to the `GITHUB_TOKEN` so the action can make calls to GitHub's rest API_
+
+#### Inputs
+
+Various inputs are defined in [`action.yml`](action.yml) to let you configure the labeler:
+
+| Name | Description | Default |
+| - | - | - |
+| `repo-token` | Token to use to authorize label changes. Typically the GITHUB_TOKEN secret | N/A |
+| `configuration-path` | The path to the label configuration file | `.github/labeler.yml` |
+| `sync-labels` | Whether or not to remove labels when matching files are reverted or no longer changed by the PR | `false`