Reorganize plugins into domain-specific groupings

.github/CODEOWNERS

@@ -10,43 +10,47 @@
 /tests/dotnet-msbuild/ @ViktorHofer @JanKrivanek
 /agentic-workflows/dotnet-msbuild/ @ViktorHofer @JanKrivanek
 
-/plugins/dotnet/skills/analyzing-dotnet-performance/ @dotnet/dotnet-diag
-/tests/dotnet/analyzing-dotnet-performance/ @dotnet/dotnet-diag
-
+# dotnet (common everyday C#/.NET)
 /plugins/dotnet/skills/csharp-scripts/ @dotnet/roslyn
 /tests/dotnet/csharp-scripts/ @dotnet/roslyn
 
 /plugins/dotnet/skills/dotnet-pinvoke/ @dotnet/appmodel
 /tests/dotnet/dotnet-pinvoke/ @dotnet/appmodel
 
-/plugins/dotnet/skills/dump-collect/ @dotnet/dotnet-diag
-/tests/dotnet/dump-collect/ @dotnet/dotnet-diag
+/plugins/dotnet/skills/nuget-trusted-publishing/ @lewing @kartheekp-ms
+/tests/dotnet/nuget-trusted-publishing/ @lewing @kartheekp-ms
+
+# dotnet-upgrade (migrating and upgrading .NET projects)
+/plugins/dotnet-upgrade/skills/thread-abort-migration/ @dotnet/appmodel
+/tests/dotnet-upgrade/thread-abort-migration/ @dotnet/appmodel
 
-/plugins/dotnet/skills/dotnet-trace-collect/ @brianrob
-/tests/dotnet/dotnet-trace-collect/ @brianrob
+/plugins/dotnet-upgrade/skills/migrate-nullable-references/ @danmoseley
+/tests/dotnet-upgrade/migrate-nullable-references/ @danmoseley
 
-/plugins/dotnet/skills/optimizing-ef-core-queries/ @dotnet/efteam
-/tests/dotnet/optimizing-ef-core-queries/ @dotnet/efteam
+/plugins/dotnet-upgrade/skills/dotnet-aot-compat/ @agocke @dotnet/appmodel
+/tests/dotnet-upgrade/dotnet-aot-compat/ @agocke @dotnet/appmodel
 
-/plugins/dotnet/skills/thread-abort-migration/ @dotnet/appmodel
-/tests/dotnet/thread-abort-migration/ @dotnet/appmodel
+# dotnet-diag (perf investigations, debugging, incident analysis)
+/plugins/dotnet-diag/skills/analyzing-dotnet-performance/ @dotnet/dotnet-diag
+/tests/dotnet-diag/analyzing-dotnet-performance/ @dotnet/dotnet-diag
 
-/plugins/dotnet/skills/migrate-nullable-references/ @danmoseley
-/tests/dotnet/migrate-nullable-references/ @danmoseley
+/plugins/dotnet-diag/skills/dump-collect/ @dotnet/dotnet-diag
+/tests/dotnet-diag/dump-collect/ @dotnet/dotnet-diag
 
-/plugins/dotnet/skills/android-tombstone-symbolication/ @dotnet/dotnet-diag 
-/tests/dotnet/android-tombstone-symbolication/ @dotnet/dotnet-diag 
+/plugins/dotnet-diag/skills/dotnet-trace-collect/ @brianrob
+/tests/dotnet-diag/dotnet-trace-collect/ @brianrob
 
-/plugins/dotnet/skills/clr-activation-debugging/ @marklio @ChrisAhna
-/tests/dotnet/clr-activation-debugging/ @marklio @ChrisAhna
+/plugins/dotnet-diag/skills/android-tombstone-symbolication/ @dotnet/dotnet-diag
+/tests/dotnet-diag/android-tombstone-symbolication/ @dotnet/dotnet-diag
 
-/plugins/dotnet/skills/microbenchmarking/ @dotnet/dotnet-perf-team
-/tests/dotnet/microbenchmarking/ @dotnet/dotnet-perf-team
+/plugins/dotnet-diag/skills/clr-activation-debugging/ @marklio @ChrisAhna
+/tests/dotnet-diag/clr-activation-debugging/ @marklio @ChrisAhna
 
-/plugins/dotnet/skills/nuget-trusted-publishing/ @lewing @kartheekp-ms
-/tests/dotnet/nuget-trusted-publishing/ @lewing @kartheekp-ms
+/plugins/dotnet-diag/skills/microbenchmarking/ @dotnet/dotnet-perf-team
+/tests/dotnet-diag/microbenchmarking/ @dotnet/dotnet-perf-team
 
-/plugins/dotnet/skills/dotnet-aot-compat/ @agocke @dotnet/appmodel
-/tests/dotnet/dotnet-aot-compat/ @agocke @dotnet/appmodel
+/plugins/dotnet-diag/agents/optimizing-dotnet-performance.agent.md @dotnet/appmodel
 
-/plugins/dotnet/agents/optimizing-dotnet-performance.agent.md @dotnet/appmodel
+# dotnet-data (data access, Entity Framework)
+/plugins/dotnet-data/skills/optimizing-ef-core-queries/ @dotnet/efteam
+/tests/dotnet-data/optimizing-ef-core-queries/ @dotnet/efteam

CONTRIBUTING.md

@@ -43,6 +43,27 @@ agentic-workflows/
 
 Every plugin must have a plugin.json file in the plugin root that is linked to from the marketplace.json file.
 
+### Plugin organization
+
+Skills are grouped into domain-specific plugins. When proposing a new skill, place it in the plugin that best matches its domain:
+
+| Plugin | Domain |
+|--------|--------|
+| `dotnet` | Common everyday C#/.NET coding tasks useful to all .NET developers |
+| `dotnet-upgrade` | Migrating and upgrading .NET projects across framework versions, language features, and compatibility targets |
+| `dotnet-diag` | Performance investigations, debugging, and incident analysis |
+| `dotnet-data` | Data access and Entity Framework |
+| `dotnet-msbuild` | MSBuild and project system |
+
+If your skill does not fit any existing plugin, consider creating a new one. The following plugin names are reserved for future use and are good candidates for new skills in those areas:
+
+- `dotnet-aspnet` — ASP.NET
+- `dotnet-wpf` — WPF
+- `dotnet-winforms` — Windows Forms (WinForms)
+- `dotnet-maui` — .NET MAUI
+
+To create a new plugin, add a `plugins/<plugin-name>/plugin.json` file and a matching entry in the marketplace.json file. See existing plugins for the expected format.
+
 ## Before you start
 
 - Search existing issues and pull requests to avoid duplicates.
@@ -108,7 +129,7 @@ description: <description of what the skill does, when to use it, and when not t
 > **Tip:** The `description` field is used by the agent runtime to decide whether to load the full skill.
 > Include **when to use** and **when not to use** guidance directly in the description so the agent can
 > select or skip skills without reading the entire `SKILL.md`. This avoids unnecessary token usage.
-> See [`thread-abort-migration/SKILL.md`](plugins/dotnet/skills/thread-abort-migration/SKILL.md) for a good example.
+> See [`thread-abort-migration/SKILL.md`](plugins/dotnet-upgrade/skills/thread-abort-migration/SKILL.md) for a good example.
 
 ### Recommended `SKILL.md` sections
 

plugins/dotnet-data/plugin.json

@@ -0,0 +1,7 @@
+{
+  "name": "dotnet-data",
+  "version": "0.1.0",
+  "description": "Skills for .NET data access and Entity Framework related tasks.",
+  "skills": "./skills/",
+  "agents": "./agents/"
+}

plugins/dotnet-diag/plugin.json

@@ -0,0 +1,7 @@
+{
+  "name": "dotnet-diag",
+  "version": "0.1.0",
+  "description": "Skills for .NET performance investigations, debugging, and incident analysis.",
+  "skills": "./skills/",
+  "agents": "./agents/"
+}

plugins/dotnet-upgrade/plugin.json

@@ -0,0 +1,7 @@
+{
+  "name": "dotnet-upgrade",
+  "version": "0.1.0",
+  "description": "Skills for migrating and upgrading .NET projects across framework versions, language features, and compatibility targets.",
+  "skills": "./skills/",
+  "agents": "./agents/"
+}

plugins/dotnet/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "dotnet",
   "version": "0.1.0",
-  "description": "Collection of core .NET skills for handling common .NET coding tasks.",
+  "description": "Common everyday C#/.NET coding skills. Expected to be useful to all .NET developers.",
   "skills": "./skills/",
   "agents": "./agents/"
 }