dotnet-project-analysis

name	dotnet-project-analysis
description	Analyzes .NET solution layout and build config -- .sln, .csproj, CPM.
allowed-tools	["Read","Grep","Glob","Bash","Write","Edit"]

dotnet-project-analysis

Analyzes .NET solution structure, project references, and build configuration. This skill is foundational -- agents need to understand project layout before doing any meaningful .NET development work.

Prerequisites: Run [skill:dotnet-version-detection] first to determine TFM and SDK version. For .NET 10+ single-file apps without a .csproj, see [skill:dotnet-file-based-apps] instead.

Scope

• Finding solution root (.sln, .slnx)
• Parsing project references and dependency graphs
• Detecting Central Package Management (CPM) configuration
• Identifying build configuration files (Directory.Build.props, Directory.Build.targets)

Out of scope

• Reading and modifying individual .csproj files -- see [skill:dotnet-csproj-reading]
• Project organization and SDK selection decisions -- see [skill:dotnet-project-structure]
• TFM/SDK version detection -- see [skill:dotnet-version-detection]

---

Step 1: Find the Solution Root

Look for solution files in the workspace, starting from the current directory and walking up to the repository root.

.sln (Legacy Format)

The traditional MSBuild solution format. Contains project paths and build configurations.

Microsoft Visual Studio Solution File, Format Version 12.00
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "MyApp", "src\MyApp\MyApp.csproj", "{GUID}"
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "MyApp.Tests", "tests\MyApp.Tests\MyApp.Tests.csproj", "{GUID}"
EndProject

Extract project entries from Project("...") lines. The second quoted value is the project name, the third is the relative path to the .csproj.

.slnx (Modern XML Format)

The new XML-based solution format (supported in .NET 10+ SDK, Visual Studio 17.13+). Preferred for new projects.

<Solution>
  <Folder Name="/src/">
    <Project Path="src/MyApp/MyApp.csproj" />
  </Folder>
  <Folder Name="/tests/">
    <Project Path="tests/MyApp.Tests/MyApp.Tests.csproj" />
  </Folder>
</Solution>

Extract project entries from <Project Path="..." /> elements. Solution folders (<Folder>) indicate logical grouping.

No Solution File

If no .sln or .slnx is found, scan for .csproj files recursively. Report: "No solution file found. Discovered N project files. Consider creating a solution with dotnet new sln and dotnet sln add."

---

Step 2: Analyze Each Project

For every .csproj discovered in Step 1, read its contents and extract the following.

Project SDK and Type

The <Project Sdk="..."> attribute identifies the project kind:

SDK	Project Type	Description
Microsoft.NET.Sdk	Class Library / Console	Default SDK, check for <OutputType>
Microsoft.NET.Sdk.Web	Web (API / MVC / Razor Pages)	ASP.NET Core web application
Microsoft.NET.Sdk.BlazorWebAssembly	Blazor WASM	Client-side Blazor (legacy SDK)
Microsoft.NET.Sdk.Worker	Worker Service	Background service / daemon
Microsoft.NET.Sdk.Razor	Razor Class Library	Shared Razor components
Microsoft.Maui.Sdk or TFMs with -android/-ios	MAUI	Cross-platform mobile/desktop
Custom or Uno.Sdk	Uno Platform	Cross-platform UI (check for Uno references)

Output Type Detection

If SDK is Microsoft.NET.Sdk, check <OutputType> to distinguish:

OutputType	Meaning
Exe	Console application
Library (or absent)	Class library
WinExe	Windows desktop (WPF/WinForms/WinUI)

Test Project Detection

A project is a test project if any of the following are true:

• <IsTestProject>true</IsTestProject> is set
• Has a PackageReference to xunit.v3, xunit, NUnit, MSTest.TestFramework, or Microsoft.NET.Test.Sdk
• Project name ends with .Tests, .UnitTests, .IntegrationTests, or .TestUtils

Blazor Project Detection

A project is Blazor if:

• SDK is Microsoft.NET.Sdk.BlazorWebAssembly
• Has <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly" />
• Has .razor files in the project directory
• Uses AddInteractiveServerComponents() or AddInteractiveWebAssemblyComponents() in startup

MAUI Project Detection

A project is MAUI if:

• <UseMaui>true</UseMaui> is set
• SDK is Microsoft.Maui.Sdk
• TFM includes platform-specific targets: net*-android, net*-ios, net*-maccatalyst, net*-windows (e.g., net8.0-android, net10.0-ios)

Uno Platform Detection

A project is Uno Platform if:

• SDK is Uno.Sdk or Uno.Sdk.Private
• Has PackageReference to Uno.WinUI or Uno.UI
• TFM includes Uno-specific targets (e.g., net*-browserwasm, net*-desktop)

---

Step 3: Map Project References

Read <ProjectReference> elements from each .csproj to build the dependency graph.

<ItemGroup>
  <ProjectReference Include="..\MyApp.Core\MyApp.Core.csproj" />
  <ProjectReference Include="..\MyApp.Infrastructure\MyApp.Infrastructure.csproj" />
</ItemGroup>

Build a dependency graph and report it:

Project Dependency Graph
========================
MyApp.Web (Web API)
  -> MyApp.Core (Library)
  -> MyApp.Infrastructure (Library)
    -> MyApp.Core (Library)
MyApp.Tests (Test)
  -> MyApp.Web (Web API)
  -> MyApp.Core (Library)

Flag issues:

• Circular references: "Project A -> B -> A detected. This will cause build failures."
• Test projects referencing other test projects: "Unusual -- test projects should reference production code, not other tests."
• Deep nesting: More than 4 levels deep may indicate over-abstraction.

---

Step 4: Detect Centralized Build Configuration

Directory.Build.props

Search for Directory.Build.props starting from each project directory up to the solution root. These files set shared MSBuild properties across all projects in their directory subtree.

Common shared properties to report:

• <TargetFramework> / <TargetFrameworks> -- shared TFM (see [skill:dotnet-version-detection])
• <LangVersion> -- C# language version
• <Nullable>enable</Nullable> -- nullable reference types
• <ImplicitUsings>enable</ImplicitUsings> -- implicit global usings
• <TreatWarningsAsErrors>true</TreatWarningsAsErrors> -- strict warnings
• <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild> -- code style enforcement
• <AnalysisLevel>latest-all</AnalysisLevel> -- analyzer severity
• <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally> -- CPM indicator

Report: "Found Directory.Build.props at <path>. Shared settings: [list properties found]. These apply to all projects under <directory>."

Directory.Build.targets

Search for Directory.Build.targets the same way. These run after project evaluation and typically contain:

• Shared <PackageReference> items (e.g., analyzers applied to all projects)
• Conditional logic based on project type
• Custom MSBuild targets

Report: "Found Directory.Build.targets at <path>. Contains: [summarize content]."

Multiple Directory.Build Files

If multiple Directory.Build.props files exist at different levels (e.g., root and src/), report the hierarchy:

Build Configuration Hierarchy
==============================
/repo/Directory.Build.props           (root: Nullable, ImplicitUsings, LangVersion)
  /repo/src/Directory.Build.props     (src: TargetFramework, TreatWarningsAsErrors)
  /repo/tests/Directory.Build.props   (tests: IsTestProject, test-specific settings)

Note: Inner files do NOT automatically import outer files. Check for <Import Project="$([MSBuild]::GetPathOfFileAbove('Directory.Build.props', '$(MSBuildThisFileDirectory)../'))" /> to see if chaining is configured.

---

Step 5: Detect Central Package Management (CPM)

Directory.Packages.props

Search for Directory.Packages.props starting from the solution root and walking upward toward the repository root (or filesystem root). NuGet resolves CPM hierarchically -- a monorepo may have Directory.Packages.props in a parent directory that governs multiple solutions. Also check for <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally> in any Directory.Build.props in the hierarchy, as CPM can be enabled there instead.

<Project>
  <PropertyGroup>
    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
  </PropertyGroup>
  <ItemGroup>
    <PackageVersion Include="Microsoft.Extensions.Logging" Version="10.0.0" />
    <PackageVersion Include="xunit.v3" Version="3.2.2" />
  </ItemGroup>
</Project>

Report:

• CPM enabled: "Central Package Management is active. Package versions are defined in Directory.Packages.props at <path>. Individual .csproj files use <PackageReference Include="..." /> without Version attributes."
• Package count: "N packages managed centrally."
• Version overrides: Check for <PackageReference ... VersionOverride="..."> in individual projects -- flag these as exceptions.
• Inherited CPM: If Directory.Packages.props is above the solution root, note: "CPM is inherited from <path> (above solution root). This is common in monorepos."

CPM Not Used

If no Directory.Packages.props is found in the upward search and ManagePackageVersionsCentrally is not set in any Directory.Build.props:

• Report: "Central Package Management is not configured. Each project defines its own package versions."
• Suggest: "Consider enabling CPM for version consistency. See [skill:dotnet-project-structure] for setup guidance."

---

Step 6: Detect Additional Configuration Files

.editorconfig

Check for .editorconfig at the solution root and nested levels. Report:

• Whether it exists
• Key rules: indent style/size, naming conventions, severity overrides
• .NET-specific sections: [*.cs] rules for dotnet_style_* and csharp_style_*

nuget.config

Search for nuget.config (case-insensitive) starting from the solution root and walking upward through parent directories. NuGet merges configuration hierarchically (project > user > machine), so multiple files may contribute to the effective config. Report all discovered files and their contents:

• Package sources configured (e.g., nuget.org, private feeds, local folders)
• Any <packageSourceMapping> entries (security best practice for supply chain)
• Any <disabledPackageSources> entries
• Note: "User-level (~/.nuget/NuGet/NuGet.Config) and machine-level configs may also affect package resolution. Run dotnet nuget list source to see the effective merged sources."

global.json

Already read by [skill:dotnet-version-detection]. Report relevant details here:

• sdk.version and sdk.rollForward policy
• msbuild-sdks section if present (custom SDK versions)

.config/dotnet-tools.json

Check for local tool manifest. Report installed tools:

• dotnet-ef -- Entity Framework Core tools
• dotnet-format -- code formatting
• nbgv -- Nerdbank.GitVersioning
• Any other tools and their versions

---

Step 7: Identify Entry Points and Key Files

Guide the agent to the most important files based on project type.

Web API / MVC / Razor Pages

• Entry point: Program.cs (top-level statements, service registration, middleware pipeline)
• Configuration: appsettings.json, appsettings.{Environment}.json
• Startup: Look for builder.Services registrations and app.Map* endpoint definitions
• Endpoints: Minimal API endpoints in Program.cs or *.cs files under an Endpoints/ directory; Controller-based in Controllers/ directory

Console Application

• Entry point: Program.cs (top-level statements or static void Main)
• Configuration: appsettings.json if using IHostBuilder / Generic Host

Worker Service

• Entry point: Program.cs with builder.Services.AddHostedService<Worker>()
• Worker: Class inheriting BackgroundService with ExecuteAsync override

Class Library

• No entry point: Document the public API surface (public classes/interfaces)
• Key files: Look for the primary namespace's types

Blazor

• Entry point: Program.cs with component registration
• Root component: App.razor or Routes.razor
• Layout: MainLayout.razor in Layout/ or Shared/
• Pages: .razor files with @page directive

MAUI

• Entry point: MauiProgram.cs with CreateMauiApp()
• App shell: AppShell.xaml for navigation structure
• Pages: Files under Views/ or Pages/ directories
• Platform-specific: Platforms/ directory with Android, iOS, Windows, Mac Catalyst folders

Test Project

• Test files: *.cs files with [Fact], [Theory], [Test], or [TestMethod] attributes
• Fixtures: Classes implementing IClassFixture<T> or ICollectionFixture<T>
• Configuration: Look for WebApplicationFactory<T> usage for integration tests

---

Structured Output Format

After completing analysis, present results in this format:

.NET Project Analysis Results
==============================
Solution:         MyApp.slnx (or MyApp.sln)
Projects:         5 (2 libraries, 1 web API, 1 console, 1 test)
CPM:              enabled (42 packages in Directory.Packages.props)
Shared Config:    Directory.Build.props (Nullable, ImplicitUsings, LangVersion=14)
Code Style:       .editorconfig present
Package Sources:  nuget.org + private feed (packageSourceMapping configured)
Local Tools:      dotnet-ef 10.0.0, nbgv 3.7.0

Project Dependency Graph
------------------------
MyApp.Api (Web API, net10.0) -> entry: src/MyApp.Api/Program.cs
  -> MyApp.Core (Library)
  -> MyApp.Infrastructure (Library)
    -> MyApp.Core (Library)
MyApp.Console (Console, net10.0) -> entry: src/MyApp.Console/Program.cs
  -> MyApp.Core (Library)
MyApp.Tests (Test, xUnit) -> entry: tests/MyApp.Tests/
  -> MyApp.Api (Web API)
  -> MyApp.Core (Library)

Key Files
---------
- Solution root:    /repo/MyApp.slnx
- Shared props:     /repo/Directory.Build.props
- Package versions: /repo/Directory.Packages.props
- API entry point:  /repo/src/MyApp.Api/Program.cs
- API config:       /repo/src/MyApp.Api/appsettings.json

---

Edge Cases

Mixed Solution Formats

If both .sln and .slnx exist, prefer .slnx (modern format). Note: "Both .sln and .slnx found. Using .slnx as primary. The .sln may be maintained for older tooling compatibility."

Monorepo with Multiple Solutions

If multiple .sln/.slnx files exist, report all of them and ask the user which solution to analyze. If one is at the repository root, default to that one.

Projects Not in Solution

If .csproj files exist that are not referenced by any solution file, report them as orphaned: "Found N project files not included in any solution. These may be experimental or unused."

Conditional ProjectReferences

If <ProjectReference> is inside a <When> or has a Condition attribute:

<ProjectReference Include="..\MyApp.DevTools\MyApp.DevTools.csproj"
                  Condition="'$(Configuration)' == 'Debug'" />

Report: "Conditional reference to MyApp.DevTools (Debug only)."

Web Project Without launchSettings.json

If a web project has no Properties/launchSettings.json, note: "No launchSettings.json found. The project uses default Kestrel settings. Consider adding launch profiles for development."