Refactor action metadata: update descriptions for clarity and consistency; ensure proper formatting in action.yml.

Author: MariusStorhaug

README.md

@@ -1,17 +1,60 @@
-# Template-Action
+# Install-PowerShell
 
-A template repository for GitHub Actions
+A cross‑platform GitHub Action that installs a specific **PowerShell Core** version—or the latest stable release—on any GitHub‑hosted runner
+(Linux, macOS, or Windows). The action automatically skips installation when the requested version is already present.
 
 ## Usage
 
-### Inputs
+Add the action to a job in your workflow file:
 
-### Secrets
-
-### Outputs
+```yaml
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
 
-### Example
+      - name: Install PowerShell
+        uses: PSModule/install-powershell@v1
+        with:
+          Version: 7.5.0
 
-```yaml
-Example here
+      - name: Run a PowerShell script
+        shell: pwsh
+        run: |
+          Write-Host "Using PowerShell $($PSVersionTable.PSVersion)"
 ```
+
+## Inputs
+
+| Input   | Required | Default | Description |
+| ------- | -------- | ------- | ----------- |
+| `Version` | `false` | `latest` | Desired PowerShell Core version (e.g. `7.4.1`). Use `latest` to install the newest stable release. |
+
+## Secrets
+
+This action does **not** require any secrets.
+
+## Outputs
+
+This action does **not** generate any outputs.
+
+## How it works
+
+* **Version resolution**
+  If `Version` is set to `latest` (case‑insensitive), the action queries the GitHub API for the newest stable release tag in the
+  `PowerShell/PowerShell` repository and substitutes that version.
+
+* **Skip logic**
+  Before installing, the action checks the current runner to see whether the requested version is already available
+  (`pwsh -Command $($PSVersionTable.PSVersion)`). If it matches, the step ends immediately.
+
+* **Platform‑specific installers**
+  | Runner OS | Install strategy |
+  | --------- | ---------------- |
+  | **Linux** (Debian/Ubuntu‑based) | Uses APT if available; otherwise downloads the `.deb` asset directly from the release page and installs with `dpkg`. |
+  | **macOS** | Prefers Homebrew Cask (`brew install --cask powershell`) and falls back to downloading the `.pkg` installer. ARCH detection (`arm64` / `x64`) is automatic. |
+  | **Windows** | Downloads the corresponding `.msi` package and installs silently with `msiexec`. |
+
+* **Error handling**
+  The step fails with a clear error message if the requested version cannot be resolved or if the operating‑system distribution is unsupported (e.g., non‑APT Linux distros).

action.yml

@@ -1,5 +1,5 @@
 name: Install PowerShell
-description: >
+description: |
   Install a specific version —or the latest stable version— of PowerShell Core
   on any GitHub runner (Linux, macOS, Windows).
   Skips the install if the requested version is already present.
@@ -10,9 +10,9 @@ branding:
 
 inputs:
   Version:
-    description: >
+    description: |
       PowerShell version to install (e.g. `7.4.1`).
-      Set to 'latest' to automatically install the newest stable release.
+      Defaults to install the latest stable release.
     required: false
     default: 'latest'