Update README

README.md

@@ -1,4 +1,26 @@
-# gha-extract-shell-scripts
+# GHA Extract Shell Scripts
 
-Extracts inline shell scripts within GitHub Action workflows for the purposes of performing
-linting and formatting checks.
+Processes the GitHub Action workflows contained within `.github/workflows` and extracts all steps which contain an embedded shell script for the purpose of running linting and formatting. Each workflow step containing a shell script will be written out to a file to make it easy to use existing tooling such as `shellcheck` and `shfmt`.
+
+## Inputs
+
+The `gha-extract-shell-scripts` action supports the following inputs:
+
+| Name                 | Description | Required | Example |
+|:---------------------|:------------|:---------|:--------|
+| `output-dir`         | Allows the user to specify the name of the directory containing the extracted workflow shell script steps. Defaults to `workflow_scripts`. | No | `workflow_scripts` |
+| `shellcheck-disable` | Ignore all the specified errors within the extracted shell scripts. | No | `SC2016,SC2050` |
+
+## Outputs
+
+| Name         | Description | Example |
+|:-------------|:------------|:--------|
+| `output-dir` | The name of the directory containing the various extracted workflow shell script steps. | `workflow_scripts` |
+
+## Permissions
+
+The following [job permissions](https://docs.github.com/en/actions/using-jobs/assigning-permissions-to-jobs) are required to run this action:
+
+```yaml
+permissions: {}
+```