09-mcp-server-resources

Demo MCP Server (.NET 10)

With Azure AD (Entra ID) Authentication. Builds on section 08. This section adds MCP Resources - read-only contextual data such as todo://schema (JSON schema) and todo://stats/dashboard (real-time statistics). Demonstrates the separation of Resources (context) vs Tools (actions).

Before you run

1. Azure AD (Entra ID): Replace <AZURE_TENANT_ID> and <AZURE_CLIENT_ID> in src/McpServerResources/appsettings.json and .vscode/launch.json (for F5 debugging).
2. Azure Storage Connection String: Replace <AZURE_STORAGE_CONNECTION_STRING> in the same files.

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MCP Server - Azure Table Storage Setup (Cheapest & Simplest)

This guide explains how to set up Azure Table Storage and connect it to a .NET MCP Server using a storage account connection string.

This approach is deliberately:

• ✅ Low cost
• ✅ Low ceremony
• ✅ Easy to understand
• ❌ Not production-grade security (by design, for teaching)

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Overview

We will:

1. Create a low-cost Azure Storage Account
2. Enable Table Storage
3. Copy the connection string
4. Store it in appsettings.json
5. Use it from C# to read/write todos

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1. Create the Azure Storage Account

In the Azure Portal:

1. Create resource → Storage account
2. Use the following settings:

Basics

• Resource group: your existing MCP server resource group
• Storage account name: any globally unique name (e.g. jcmpserverdemo01)
• Region: same as your Container App
• Performance: Standard
• Replication: Locally-redundant storage (LRS)
• Preferred storage type:
  👉 Other (tables and queues)

This is the cheapest possible configuration that supports Azure Table Storage.

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2. Security & Networking (keep it simple)

You can leave most settings as default.

Important points:

• Public network access: Enabled
• Secure transfer required: Enabled
• Storage account key access: Enabled

We intentionally allow key-based access to avoid managed identity and RBAC complexity in this demo.

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3. Create the Table

After the storage account is created:

MCP Resources best practices

This server demonstrates the following MCP resource patterns:

Resources vs Tools

A key best practice in MCP is the separation of Resources and Tools:

• Resources are for read-only contextual information. This includes:
  • System schemas and metadata (todo://schema)
  • Real-time dashboards and statistics (todo://stats/dashboard)
  • Documentation or background context that helps the AI understand the environment.
• Tools are for actions and data manipulation. This includes:
  • CRUD operations on individual records (GetTodo, AddTodo, UpdateTodo)
  • Executing specific tasks or workflows.

Why this matters: Resources are designed to provide the AI model with "context" to its environment. Using resources to access individual records from a database is an anti-pattern because:

1. It bloats the resource list with thousands of items.
2. It doesn't provide meaningful context for the model's reasoning process.
3. Tools are better suited for targeted data retrieval and modification.

Dynamic Resources

The todo://stats/dashboard resource demonstrates the Dynamic Resource pattern. These are resources that change as the underlying data changes and support Subscriptions, allowing the client to receive updates whenever the system state changes.