sametbrr/dotnet-api-mcp

.NET Core API MCP Server

A Model Context Protocol (MCP) server that enables Claude AI to interact with .NET Core APIs through CRUD operations and Swagger/OpenAPI integration.

Features

• HTTP Methods Support (GET, POST, PUT, DELETE, PATCH)
• Swagger/OpenAPI Integration
• Multi-environment Configuration (local, development, beta, production)
• Automatic Endpoint Discovery
• Model/Schema Tracking
• Dynamic Query Parameters
• Authentication Support
• Configurable Timeouts & Headers

Quick Start Guide

Step 1: Choose Your Platform

Option A: Claude Desktop

Install the package:

npm install -g dotnet-api-mcp

Configure Claude Desktop:

1. Open your Claude Desktop config file:

   • macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
   • Windows: %APPDATA%\Claude\claude_desktop_config.json

2. Add the MCP server configuration:

{
  "mcpServers": {
    "dotnet-api": {
      "command": "npx",
      "args": ["-y", "dotnet-api-mcp"],
      "env": {}
    }
  }
}

3. Restart Claude Desktop

Option B: Claude Code (VSCode)

Step 1.1: Install the package in your project:

npm install dotnet-api-mcp

Step 1.2: Add MCP server to Claude Code:

claude mcp add dotnet-api-mcp dotnet-api-mcp

Step 1.3: Restart VSCode

Step 2: Create Configuration File

Create a config.json file in your project root directory (where package.json is located):

Option 1 - Copy from example:

cp node_modules/dotnet-api-mcp/config.example.json config.json

Option 2 - Create manually:

Create config.json with the following structure:

{
  "environments": {
    "local": {
      "baseUrl": "https://localhost:7000/api",
      "swaggerUrl": "https://localhost:7000/swagger/v1/swagger.json",
      "auth": {
        "email": "your-email@example.com",
        "password": "your-password"
      }
    }
  },
  "activeEnvironment": "local",
  "timeout": 30000,
  "headers": {
    "Content-Type": "application/json",
    "Accept": "application/json"
  }
}

Step 3: Configure Your API Settings

Update config.json with your actual API information:

Required Fields:

1. baseUrl: Your API base URL

   "baseUrl": "https://localhost:7000/api"
   

   ⚠️ Warning: If missing, API requests will fail with "No base URL configured"

2. swaggerUrl: Your Swagger/OpenAPI documentation URL

   "swaggerUrl": "https://localhost:7000/swagger/v1/swagger.json"
   

   ⚠️ Warning: If missing, Swagger tools won't work

Optional Fields:

3. auth (if your API requires authentication):

   "auth": {
     "email": "your-email@example.com",
     "password": "your-password"
   }
   

   ℹ️ Info: You can omit this section if your API doesn't require authentication

4. timeout (default: 30000ms):

   "timeout": 30000
   

   ℹ️ Info: Increase if your API responses are slow

5. headers (custom HTTP headers):

   "headers": {
     "Content-Type": "application/json",
     "Accept": "application/json"
   }
   

   ℹ️ Info: Add any custom headers your API requires

Step 4: Add Multiple Environments (Optional)

You can configure multiple environments for different stages:

{
  "environments": {
    "local": {
      "baseUrl": "https://localhost:7000/api",
      "swaggerUrl": "https://localhost:7000/swagger/v1/swagger.json"
    },
    "development": {
      "baseUrl": "https://dev-api.example.com/api",
      "swaggerUrl": "https://dev-api.example.com/swagger/v1/swagger.json"
    },
    "beta": {
      "baseUrl": "https://beta-api.example.com/api",
      "swaggerUrl": "https://beta-api.example.com/swagger/v1/swagger.json"
    },
    "production": {
      "baseUrl": "https://api.example.com/api",
      "swaggerUrl": "https://api.example.com/swagger/v1/swagger.json"
    }
  },
  "activeEnvironment": "local"
}

⚠️ Warning: Always set activeEnvironment to specify which environment to use.

Step 5: Verify Installation

Ask Claude to test the connection:

"Fetch the Swagger documentation from my API"

If successful, you'll see the API endpoints. If not, check these common issues:

Common Issues:

Configuration Reference

Complete config.json Example

{
  "environments": {
    "local": {
      "baseUrl": "https://localhost:7000/api",
      "swaggerUrl": "https://localhost:7000/swagger/v1/swagger.json",
      "auth": {
        "email": "user@example.com",
        "password": "password123"
      }
    }
  },
  "activeEnvironment": "local",
  "timeout": 30000,
  "headers": {
    "Content-Type": "application/json",
    "Accept": "application/json",
    "X-Custom-Header": "custom-value"
  }
}

Environment Switching

To switch between environments, update activeEnvironment:

{
  "activeEnvironment": "production"
}

Available Tools

HTTP Request Tools

api_get

Make GET requests to your API

// List all users
api_get("/users")

// Get user by ID with params
api_get("/users/123", { include: "profile" })

api_post

Make POST requests to create resources

api_post("/users", {
  "name": "John Doe",
  "email": "john@example.com"
})

api_put

Make PUT requests to update resources

api_put("/users/123", {
  "name": "Jane Doe",
  "email": "jane@example.com"
})

api_delete

Make DELETE requests

api_delete("/users/123")

api_patch

Make PATCH requests for partial updates

api_patch("/users/123", {
  "email": "newemail@example.com"
})

Swagger/OpenAPI Tools

swagger_fetch

Fetch Swagger/OpenAPI documentation

swagger_fetch({ environment: "beta" })

swagger_list_endpoints

List all API endpoints

// List all endpoints
swagger_list_endpoints()

// Filter by tag
swagger_list_endpoints({ tag: "User" })

// Filter by method
swagger_list_endpoints({ method: "POST" })

swagger_get_endpoint

Get detailed information about a specific endpoint

swagger_get_endpoint({
  path: "/api/users/{id}",
  method: "GET"
})

swagger_get_schema

Get model/schema definition from Swagger

swagger_get_schema({ schemaName: "UserDto" })

Usage Examples

With Claude Desktop

You: "Fetch the Swagger documentation for my API"
Claude: [Uses swagger_fetch tool]

You: "List all users from the beta environment"
Claude: [Uses api_get with /users endpoint]

You: "Create a new product with name 'Laptop' and price 999"
Claude: [Uses api_post with /products endpoint]

Programmatic Usage

import { spawn } from 'child_process';

const mcp = spawn('node', ['node_modules/dotnet-api-mcp/src/index.js']);

// MCP server is now running and can receive requests

Development

Running Locally

git clone https://github.com/sametbrr/dotnet-api-mcp.git
cd dotnet-api-mcp
npm install
npm start

Development Mode (with auto-reload)

npm run dev

Troubleshooting

Connection Issues

• Verify your API URL in config.json
• Check if API accepts CORS requests
• Ensure SSL certificates are valid

Authentication Errors

• Update auth credentials in config.json
• Check if API requires token-based auth

Swagger Not Loading

• Verify swaggerUrl is accessible
• Ensure Swagger JSON endpoint is exposed

Requirements

• Node.js >= 18.0.0
• .NET Core API with Swagger/OpenAPI support

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

MIT License - see LICENSE file for details

Author

Samet Birer

Links

• GitHub Repository
• NPM Package
• Report Issues
• Model Context Protocol