[プレビュー] Azure Functions をリモート MCP サーバーとして使えるようになったので試してみた

% docker run -p 10000:10000 -p 10001:10001 -p 10002:10002 \
    mcr.microsoft.com/azure-storage/azurite
Unable to find image 'mcr.microsoft.com/azure-storage/azurite:latest' locally
latest: Pulling from azure-storage/azurite
6e771e15690e: Already exists 

:

Azurite Blob service is starting at http://0.0.0.0:10000
Azurite Blob service is successfully listening at http://0.0.0.0:10000
Azurite Queue service is starting at http://0.0.0.0:10001
Azurite Queue service is successfully listening at http://0.0.0.0:10001
Azurite Table service is starting at http://0.0.0.0:10002
Azurite Table service is successfully listening at http://0.0.0.0:10002

brew tap azure/functions
brew install azure-functions-core-tools@4
# if upgrading on a machine that has 2.x or 3.x installed:
brew link --overwrite azure-functions-core-tools@4

% func start
  Determining projects to restore...
  Restored /Users/iwasa.takahito/work/hoge0422azurefunc/remote-mcp-functions-dotnet/src/FunctionsMcpTool.csproj (in 5.14 sec).
/Users/iwasa.takahito/work/hoge0422azurefunc/remote-mcp-functions-dotnet/src/SnippetsTool.cs(8,49): warning CS9113: Parameter 'logger' is unread. [/Users/iwasa.takahito/work/hoge0422azurefunc/remote-mcp-functions-dotnet/src/FunctionsMcpTool.csproj]
  Determining projects to restore...
  Restored /Users/iwasa.takahito/work/hoge0422azurefunc/remote-mcp-functions-dotnet/src/obj/Debug/net8.0/WorkerExtensions/WorkerExtensions.csproj (in 4.13 sec).
  WorkerExtensions -> /Users/iwasa.takahito/work/hoge0422azurefunc/remote-mcp-functions-dotnet/src/obj/Debug/net8.0/WorkerExtensions/buildout/Microsoft.Azure.Functions.Worker.Extensions.dll
  FunctionsMcpTool -> /Users/iwasa.takahito/work/hoge0422azurefunc/remote-mcp-functions-dotnet/src/bin/output/FunctionsMcpTool.dll

Build succeeded.

/Users/iwasa.takahito/work/hoge0422azurefunc/remote-mcp-functions-dotnet/src/SnippetsTool.cs(8,49): warning CS9113: Parameter 'logger' is unread. [/Users/iwasa.takahito/work/hoge0422azurefunc/remote-mcp-functions-dotnet/src/FunctionsMcpTool.csproj]
    1 Warning(s)
    0 Error(s)

Time Elapsed 00:00:14.60

Azure Functions Core Tools
Core Tools Version:       4.0.7030 Commit hash: N/A +bb4c949899cd5659d6bfe8b92cc923453a2e8f88 (64-bit)
Function Runtime Version: 4.1037.0.23568

[2025-04-21T20:23:24.563Z] Found /Users/iwasa.takahito/work/hoge0422azurefunc/remote-mcp-functions-dotnet/src/FunctionsMcpTool.csproj. Using for user secrets file configuration.
[2025-04-21T20:23:25.375Z] MCP server SSE endpoint: http://localhost:7071/runtime/webhooks/mcp/sse
[2025-04-21T20:23:27.225Z] Worker process started and initialized.

Functions:

        GetSnippet: mcpToolTrigger

        SaveSnippet: mcpToolTrigger

        SayHello: mcpToolTrigger

For detailed output, run func with --verbose flag.
[2025-04-21T20:23:32.267Z] Host lock lease acquired by instance ID '000000000000000000000000BA677196'.

{
  "mcpServers": {
    "Azure Functions Local": {
      "command": "npx",
      "args": [
        "mcp-remote",
        "http://localhost:7071/runtime/webhooks/mcp/sse"
      ]
    }
  }
}

% azd auth login
  Logged in to Azure as admin@aad.tak1wa.com
% azd up        
  (✓) Done: Downloading Bicep
? Select an Azure Subscription to use:  1. hoge subscription (a50aeedb-979c-428f-8b2d-28974d5e3d3b)
? Enter a value for the 'location' infrastructure parameter:  7. (US) East US (eastus)
? Enter a value for the 'vnetEnabled' infrastructure parameter: False

Packaging services (azd package)

  (✓) Done: Packaging service api
  - Package Output: /var/folders/4d/nhd1bp3d161crsn900wjrprm0000gp/T/remote-mcp-functions-dotnet-api-azddeploy-1745267851.zip

Provisioning Azure resources (azd provision)
Provisioning Azure resources can take some time.

Subscription: hoge subscription (a50aeedb-979c-428f-8b2d-28974d5e3d3b)
Location: East US

  You can view detailed progress in the Azure Portal:
  https://portal.azure.com/#view/HubsExtension/DeploymentDetailsBlade/~/overview/id/%2Fsubscriptions%2Fa50aeedb-979c-428f-8b2d-28974d5e3d3b%2Fproviders%2FMicrosoft.Resources%2Fdeployments%2Fhoge0422-1745267855

  (✓) Done: Resource group: rg-hoge0422 (5.232s)
  (✓) Done: App Service plan: plan-tehexyshtiewy (9.582s)
  (✓) Done: Storage account: sttehexyshtiewy (23.55s)
  (✓) Done: Log Analytics workspace: log-tehexyshtiewy (19.404s)
  (✓) Done: Application Insights: appi-tehexyshtiewy (4.844s)
  (✓) Done: Function App: func-api-tehexyshtiewy (25.778s)

Deploying services (azd deploy)

  (✓) Done: Deploying service api
  - Endpoint: https://func-api-tehexyshtiewy.azurewebsites.net/


SUCCESS: Your up workflow to provision and deploy to Azure completed in 2 minutes 31 seconds.

namespace FunctionsSnippetTool;

internal sealed class ToolsInformation
{
    public const string SaveSnippetToolName = "save_snippet";
    public const string SaveSnippetToolDescription =
        "Saves a code snippet into your snippet collection.";
    public const string GetSnippetToolName = "get_snippets";
    public const string GetSnippetToolDescription =
        "Gets code snippets from your snippet collection.";
    public const string SnippetNamePropertyName = "snippetname";
    public const string SnippetPropertyName = "snippet";
    public const string SnippetNamePropertyDescription = "The name of the snippet.";
    public const string SnippetPropertyDescription = "The code snippet.";
    public const string PropertyType = "string";
    public const string HelloToolName = "hello";
    public const string HelloToolDescription =
        "Simple hello world MCP Tool that responses with a hello message.";
}

using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Extensions.Mcp;
using Microsoft.Extensions.Logging;
using static FunctionsSnippetTool.ToolsInformation;

namespace FunctionsSnippetTool;

public class HelloTool(ILogger<SnippetsTool> logger)
{
    [Function(nameof(SayHello))]
    public string SayHello(
        [McpToolTrigger(HelloToolName, HelloToolDescription)] ToolInvocationContext context
    )
    {
        logger.LogInformation("Saying hello");
        return "Hello I am MCP Tool!";
    }
}