microsoft--agent-framework/dotnet/samples/02-agents/ModelContextProtocol/FoundryAgent_Hosted_MCP/README.md

Prerequisites

Before you begin, ensure you have the following prerequisites:

• .NET 10 SDK or later
• Microsoft Foundry service endpoint and deployment configured
• Azure CLI installed and authenticated (for Azure credential authentication)

Note: This demo uses Azure CLI credentials for authentication. Make sure you're logged in with az login and have access to the Microsoft Foundry resource. For more information, see the Azure CLI documentation.

Set the following environment variables:

$env:FOUNDRY_PROJECT_ENDPOINT="https://your-foundry-service.services.ai.azure.com/api/projects/your-foundry-project" # Replace with your Microsoft Foundry resource endpoint
$env:FOUNDRY_MODEL="gpt-5.4-mini"  # Optional, defaults to gpt-5.4-mini

Authenticating a hosted MCP server with a Foundry project connection

A hosted MCP server can authenticate through a Foundry project connection instead of an inline authorization token or headers. The connection stores the credentials and the platform injects them at request time. This mirrors the Python FoundryChatClient.get_mcp_tool(..., project_connection_id=...).

Use the FoundryAITool.CreateMcpTool overload that takes a projectConnectionId:

using Microsoft.Agents.AI.Foundry;
using OpenAI.Responses;

AITool tool = FoundryAITool.CreateMcpTool(
    serverLabel: "github",
    serverUri: new Uri("https://api.githubcopilot.com/mcp"),
    projectConnectionId: "my-foundry-connection",
    toolCallApprovalPolicy: new McpToolCallApprovalPolicy(GlobalMcpToolCallApprovalPolicy.AlwaysRequireApproval));

The resulting tool sends project_connection_id on the MCP tool to Foundry.