Visual Studio Integration
REST API Client Code Generator provides seamless integration across all major Visual Studio platforms with consistent functionality and user experience.

Add a new REST API Client directly from the Visual Studio Add menu

Configure your OpenAPI specification URL, namespace, and code generator
Supported Platforms
- Visual Studio 2017, 2019, 2022 - Full integration with all modern Visual Studio versions
- Visual Studio Code - Context menu integration for JSON and YAML files
- Visual Studio for Mac - Complete feature parity across platforms

Right-click context menu options in Solution Explorer for quick access to code generation
Code Generators
Custom Tools
Custom tools let you associate a tool with an item in a project and run that tool whenever the file is saved, enabling automatic code regeneration when your OpenAPI specifications change.
NSwagCodeGenerator
Version: v14.4.0
Generates a single file C# REST API Client using the NSwag.CodeGeneration.CSharp NuGet package. Produces clean, strongly-typed code with full async support and comprehensive error handling.
Key Features:
- Strongly-typed client generation
- Full async/await support
- Comprehensive exception handling
- Integration with ASP.NET Core
OpenApiCodeGenerator
Version: v7.14.0
Generates a single file C# REST API Client using OpenAPI Generator. The output file merges all generated files using the command: generate -g csharp --input-spec [swagger file] --output [output file] -DapiTests=false -DmodelTests=false -DpackageName=[namespace] --skip-overwrite
Configuration Options:
- Generate Multiple Files support
- Extensive customization properties
- Template customization
- Multiple output formats
KiotaCodeGenerator
Version: v1.27.0
Generates a single file C# REST API Client using Microsoft Kiota. The output merges files generated with: generate -l CSharp -d [swagger file] -o [output file] -n [namespace]
Microsoft Integration:
- Microsoft Graph API support
- Azure authentication patterns
- Modern .NET practices
- Strong typing and validation
SwaggerCodeGenerator
Version: v3.0.34
Generates a single file C# REST API Client using Swagger Codegen CLI. Uses the command: generate -l csharp --input-spec [swagger file] --output [output file] -DapiTests=false -DmodelTests=false -DpackageName=[namespace] --skip-overwrite
Proven Reliability:
- Extensive language support
- Legacy project compatibility
- Established workflow integration
- Community-driven templates
AutoRestCodeGenerator
Version: v3.0.0-beta.20210504.2 (v3), v2.0.4417 (v2)
Generates a single file C# REST API Client using AutoRest. Equivalent to: --csharp --input-file=[swagger file] --output-file=[output file] --namespace=[namespace] --add-credentials
Enterprise Features:
- Azure service optimization
- Advanced authentication
- Retry policies and timeout configuration
- Enterprise-grade reliability
RefitterCodeGenerator
Version: v1.6.0
Generates a single file C# REST API Client interface for Refit using Refitter.Core. Combines a Refit interface generated by Refitter with contracts generated using NSwag.CodeGeneration.CSharp.
Reactive Patterns:
- Refit interface generation
- Reactive programming support
- Clean interface design
- Comprehensive testing capabilities
Configuration File Support

Generate code from NSwag Studio .nswag configuration files

Refitter .refitter settings file integration

Microsoft Kiota kiota-lock.json configuration support
Generate code using configuration files:
.nswag
configuration files from NSwagStudio by including it in the project and using the Generate NSwag Studio output context menu.refitter
settings files from Refitter by including it in the project and using the Generate Refitter output context menukiota-lock.json
configuration files from Microsoft Kiota by including it in the project and using the Generate Kiota output context menu
Auto-Generation Features
🔄 Automatic Code Regeneration
Custom tools automatically regenerate client code whenever your OpenAPI specification files change, keeping your code always in sync with your API.
- Auto-updating of generated code file when changes are made to the OpenAPI specification JSON or YAML file
- Custom namespace definition for the generated file
- Multiple file generation support for OpenAPI Generator and Kiota (configurable in settings)
- Context menu integration for quick access to generation options
Advanced Configuration
Settings and Customization
The extension provides extensive configuration options for each code generator, accessible through the Visual Studio Tools menu.

General settings for Java, NPM, and tool paths

NSwag-specific configuration options

OpenAPI Generator customization settings
Customizable Settings
Environment Configuration
- Java path configuration - Specify custom Java installation paths
- NPM and Node.js paths - Configure custom Node.js environments
- JAR file locations - Use existing Swagger Codegen CLI and OpenAPI Generator JAR files
Generator-Specific Options
- AutoRest Customization - Support for all C# generator settings, custom authentication schemes, retry policies
- NSwag Customization - Full access to NSwag package properties, custom serialization settings, advanced type mapping
- OpenAPI Generator Options - Access to additional properties, template customization, multiple output formats

AutoRest generator configuration

Refitter customization settings

Microsoft Kiota configuration options
Cross-Platform Support
Visual Studio Code Integration

VS Code command palette integration

Context menu support for C# generation in VS Code

TypeScript code generation support in VS Code
Visual Studio for Mac

Visual Studio for Mac "Add New" menu integration

OpenAPI specification configuration dialog on macOS

Code generation context menu in Visual Studio for Mac
Dependencies and Requirements
Automatic Dependency Management
The Visual Studio Extension automatically adds the required NuGet packages that the generated code depends on:
NSwag Dependencies
- Newtonsoft.Json - JSON serialization
OpenAPI Generator Dependencies
- RestSharp - HTTP client library
- JsonSubTypes - Polymorphic JSON serialization
- Polly - Resilience and fault-handling library
- Newtonsoft.Json - JSON serialization
Microsoft Kiota Dependencies
- Microsoft.Kiota.Abstractions
- Microsoft.Kiota.Http.HttpClientLibrary
- Microsoft.Kiota.Serialization.* packages
- Microsoft.Kiota.Authentication.Azure
- Azure.Identity
Refitter Dependencies
- Refit - REST library for .NET
Swagger Codegen CLI Dependencies
- RestSharp - HTTP client library
- JsonSubTypes - Polymorphic JSON serialization
AutoRest Dependencies
- Microsoft.Rest.ClientRuntime
- Newtonsoft.Json - JSON serialization
Runtime Requirements
- Java Runtime Environment - Required for Swagger Codegen CLI and OpenAPI Generator
- NPM - Required for AutoRest and NSwag CLI installations
- .NET 7.0 - Required for Microsoft Kiota
📦 On-Demand Installation
The Swagger Codegen CLI and OpenAPI Generator are distributed as JAR files and downloaded on demand. AutoRest is installed via NPM as a global tool, and Microsoft Kiota is installed as a .NET Tool - all automatically managed for you.
Analytics and Error Reporting

Analytics and error reporting configuration options
- Anonymous usage tracking - Helps improve the tool through Exceptionless and Azure Application Insights
- Error reporting - Automatic error collection to improve stability and user experience
- Privacy-focused - Uses secure hash of username@host for anonymous identification
- Configurable - Can be completely disabled through the settings panel
Custom Tool Examples

NSwag custom tool configuration in file properties

OpenAPI Generator custom tool setup

Swagger Codegen CLI custom tool configuration