[docs] Update documentation for features from 2026-04-07

docs/src/content/docs/guides/compilation.md

@@ -61,6 +61,8 @@ target: copilot  # or vscode, claude, codex, or all
 3. **Optimization**: Applies mathematical context optimization (see below)
 4. **Format Generation**: Outputs native files for each target agent format
 
+> **Tip**: `apm compile` warns when any `.instructions.md` file is missing an `applyTo` frontmatter field. An instruction without `applyTo` applies globally and cannot be scoped to specific paths. Add `applyTo` to keep context focused.
+
 ### Example Output
 
 **After `apm compile`:**

docs/src/content/docs/guides/marketplaces.md

@@ -75,6 +75,8 @@ This registers the marketplace and fetches its `marketplace.json`. By default AP
 - `--name/-n` -- Custom display name for the marketplace
 - `--branch/-b` -- Branch to track (default: `main`)
 
+> **GitHub Enterprise**: `apm marketplace add` respects the `GITHUB_HOST` environment variable. Set it to your GHES hostname to register marketplaces hosted on a GitHub Enterprise Server instance. See [Authentication](../../getting-started/authentication/) for details.
+
 ```bash
 # Register with a custom name on a specific branch
 apm marketplace add acme/plugin-marketplace --name acme-plugins --branch release

docs/src/content/docs/guides/skills.md

@@ -383,6 +383,16 @@ If skill lacks APM metadata:
 1. Check the skill was installed via APM (not manually copied)
 2. Reinstall the package
 
+### Duplicate Skill Name Warning
+
+If two installed packages deploy a native skill with the same name, APM warns about the conflict:
+
+```
+[!] Skill name conflict: "code-review" deployed by both owner/pkg-a and owner/pkg-b
+```
+
+The last-installed package wins. To resolve: uninstall one of the conflicting packages, or use packages that use distinct skill names.
+
 ## Related Documentation
 
 - [Core Concepts](../../introduction/how-it-works/) - Understanding APM architecture