C# Skill - Roslyn-Powered Code Analysis CLI

A command-line tool for C# code analysis and refactoring using Roslyn APIs. Provides fast, accurate, token-efficient operations for working with C# codebases.

Features

• 18 Commands across 7 categories for comprehensive code analysis
• Symbol-aware operations that understand C# semantics
• Safe refactoring with preview mode
• Multiple output formats: JSON, Text, Markdown
• Fast and accurate using Roslyn compiler APIs

Installation

git clone <repository-url>
cd csharp-skill
dotnet build

Usage

dotnet run -- [command] [options]

# Or after building, use the executable directly:
./bin/Debug/net10.0/csharp-skill [command] [options]

Global Options

• --solution, -s <path> - Path to .sln file (optional - auto-discovers if not specified)
• --project, -p <path> - Path to .csproj file (alternative to solution, also auto-discovers)
• --output, -o <format> - Output format: json, text, or markdown (default: json)
• --verbose, -v - Enable verbose logging

Auto-Discovery: If you don't specify -s or -p, the tool automatically searches the current directory for a .sln file (preferred) or .csproj file. Perfect for running commands from your project root!

Commands

Symbol Commands

find-definition

Find where a symbol (class, method, property, etc.) is defined.

csharp-skill -s MySolution.sln find-definition UserService --type class
csharp-skill -s MySolution.sln find-definition GetById --type method --in-namespace MyApp.Services

Options:

• --type, -t - Filter by symbol type: class, method, property, field, interface, enum
• --in-file, -f - Search only in specific file
• --in-namespace, -n - Search only in specific namespace

find-references

Find all references/usages of a symbol throughout the solution.

csharp-skill -s MySolution.sln find-references GetById --type method
csharp-skill -s MySolution.sln find-references IUserRepository --type interface

Options:

• --type, -t - Symbol type to search for
• --in-namespace, -n - Symbol namespace

signature

Get the signature and documentation of a symbol.

csharp-skill -s MySolution.sln signature GetById --type method --include-overloads
csharp-skill -s MySolution.sln signature UserService --type class

Options:

• --type, -t - Type of symbol
• --include-overloads - Show all overloads for methods
• --include-docs - Include XML documentation comments (default: true)

list-members

List all members (methods, properties, fields) of a type.

csharp-skill -s MySolution.sln list-members UserService
csharp-skill -s MySolution.sln list-members User --kind method --accessibility public

Options:

• --kind, -k - Filter by member kind: method, property, field, event
• --accessibility, -a - Filter by accessibility: public, private, protected, internal
• --include-inherited - Include inherited members

rename

Safely rename a symbol across the entire solution.

# Preview mode (show changes without applying)
csharp-skill -s MySolution.sln rename UserService UserManager --preview

# Apply rename
csharp-skill -s MySolution.sln rename UserService UserManager --type class --rename-file

# Rename method
csharp-skill -s MySolution.sln rename GetById FindById --type method

Options:

• --type, -t - Type of symbol being renamed
• --in-namespace, -n - Limit scope to namespace
• --preview - Show changes without applying them
• --rename-file - Also rename the file if renaming a type

Compilation Commands

diagnostics

Get all compilation errors, warnings, and info messages.

csharp-skill -s MySolution.sln diagnostics --severity error
csharp-skill -s MySolution.sln diagnostics --file src/UserService.cs --severity warning
csharp-skill -s MySolution.sln diagnostics --code CS0246

Options:

• --severity, -s - Filter by severity: error, warning, info
• --file, -f - Get diagnostics only for specific file
• --code, -c - Filter by diagnostic code (e.g., CS0246)

check-symbol-exists

Quickly verify if a symbol exists and is accessible.

csharp-skill -s MySolution.sln check-symbol-exists UserDto --type class
csharp-skill -s MySolution.sln check-symbol-exists GetById --type method --in-namespace MyApp.Services

Options:

• --type, -t - Expected symbol type
• --in-namespace, -n - Expected namespace

Type Hierarchy Commands

find-implementations

Find all implementations of an interface or abstract class.

csharp-skill -s MySolution.sln find-implementations IUserRepository
csharp-skill -s MySolution.sln find-implementations IDisposable

inheritance-tree

Show inheritance hierarchy (ancestors and descendants).

csharp-skill -s MySolution.sln inheritance-tree UserService
csharp-skill -s MySolution.sln inheritance-tree BaseService --direction down

Options:

• --direction, -d - Show ancestors, descendants, or both (default: both)

Call Analysis Commands

find-callers

Find all methods that call a specific method.

csharp-skill -s MySolution.sln find-callers GetById
csharp-skill -s MySolution.sln find-callers ProcessOrder

find-callees

Find all methods called by a specific method.

csharp-skill -s MySolution.sln find-callees GetUser
csharp-skill -s MySolution.sln find-callees ProcessOrder

Dependency Analysis Commands

dependencies

Analyze what types/namespaces a file or type depends on.

csharp-skill -s MySolution.sln dependencies src/Controllers/UserController.cs
csharp-skill -s MySolution.sln dependencies UserService

unused-code

Find potentially unused code (methods, classes, properties).

csharp-skill -s MySolution.sln unused-code

Code Generation Commands

generate-interface

Extract an interface from a class.

csharp-skill -s MySolution.sln generate-interface UserService
csharp-skill -s MySolution.sln generate-interface UserService -o text

implement-interface

Generate implementation stubs for an interface.

csharp-skill -s MySolution.sln implement-interface IUserRepository
csharp-skill -s MySolution.sln implement-interface IDisposable

Organization Commands

list-types

List all types in a namespace or file.

csharp-skill -s MySolution.sln list-types --namespace MyApp.Services
csharp-skill -s MySolution.sln list-types

Options:

• --namespace - Filter by namespace

namespace-tree

Show the namespace hierarchy of the solution.

csharp-skill -s MySolution.sln namespace-tree
csharp-skill -s MySolution.sln namespace-tree -o markdown

analyze-file

Quick comprehensive analysis of a single file.

csharp-skill -s MySolution.sln analyze-file src/Services/UserService.cs
csharp-skill -s MySolution.sln analyze-file src/Program.cs -o markdown

Output Formats

JSON (default)

csharp-skill -s MySolution.sln find-definition UserService -o json

{
  "symbol": "UserService",
  "kind": "class",
  "location": {
    "file": "src/Services/UserService.cs",
    "line": 15,
    "column": 18
  },
  "namespace": "MyApp.Services",
  "accessibility": "public"
}

Text

csharp-skill -s MySolution.sln find-definition UserService -o text

Symbol: UserService
Kind: class
Location: File: src/Services/UserService.cs
          Line: 15
          Column: 18
Namespace: MyApp.Services
Accessibility: public

Markdown

csharp-skill -s MySolution.sln find-definition UserService -o markdown

**Symbol**: UserService
**Kind**: class
**Location**: ...

Example Workflows

Workflow 1: Safe Refactoring

# 1. Check current usage
csharp-skill -s MySolution.sln find-references GetById --type method

# 2. Preview rename
csharp-skill -s MySolution.sln rename GetById FindById --type method --preview

# 3. Execute rename
csharp-skill -s MySolution.sln rename GetById FindById --type method

# 4. Verify no errors
csharp-skill -s MySolution.sln diagnostics --severity error

Workflow 2: Understanding a Type

# 1. Find where it's defined
csharp-skill -s MySolution.sln find-definition UserService

# 2. See its members
csharp-skill -s MySolution.sln list-members UserService

# 3. Check inheritance
csharp-skill -s MySolution.sln inheritance-tree UserService

# 4. See what it depends on
csharp-skill -s MySolution.sln dependencies UserService

Workflow 3: Code Quality

# 1. Check for compilation errors
csharp-skill -s MySolution.sln diagnostics --severity error

# 2. Find unused code
csharp-skill -s MySolution.sln unused-code

# 3. Analyze specific file
csharp-skill -s MySolution.sln analyze-file src/Services/UserService.cs

Exit Codes

• 0 - Success
• 1 - General error (exception, invalid arguments)
• 2 - Not found (symbol not found, file not found)

Requirements

• .NET 10.0 Runtime - Required to run the tool
  • Download: https://dotnet.microsoft.com/download/dotnet/10.0
  • The binaries are framework-dependent and require .NET 10.0 to be installed
• Solution or project file to analyze

Architecture

The tool is built on three main components:

1. RoslynApiClient - Wrapper around Roslyn APIs for symbol operations
2. Command Handlers - 18 command implementations using System.CommandLine
3. Output Formatters - JSON/text/markdown output generation

All source code is located in src/CSharpExpertCli/.

Technical Details

Dependencies

• Microsoft.CodeAnalysis.CSharp.Workspaces (v5.0.0)
• Microsoft.CodeAnalysis.Workspaces.MSBuild (v5.0.0)
• Microsoft.Build.Locator (v1.8.1)
• System.CommandLine (v2.0.0-beta4.22272.1)

Key Features

• Uses Roslyn's SymbolFinder for accurate symbol lookups
• Leverages SemanticModel for type information
• Safe renaming via Renamer API
• Compilation diagnostics from full solution analysis

Contributing

This tool implements all 18 commands specified in SPEC.md.

License

[Your License Here]

Support

For issues or questions, please refer to the specification document or open an issue.