agent-framework/dotnet/samples/02-agents/AgentsWithFoundry/Agent_Step12_Middleware

Middleware with the Responses API

This sample demonstrates multiple middleware layers working together: PII filtering, guardrails, function invocation logging, and human-in-the-loop approval.

What this sample demonstrates

• Agent-level run middleware (PII filtering, guardrail enforcement)
• Function-level middleware (logging, result overrides)
• Human-in-the-loop approval workflows for sensitive function calls
• Using .AsBuilder().Use() to compose middleware
• No server-side agent creation or cleanup required

Prerequisites

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

Set the following environment variables:

$env:AZURE_AI_PROJECT_ENDPOINT="https://your-foundry-service.services.ai.azure.com/api/projects/your-foundry-project"
$env:AZURE_AI_MODEL_DEPLOYMENT_NAME="gpt-5.4-mini"

Run the sample

cd dotnet/samples/02-agents/AgentsWithFoundry
dotnet run --project .\Agent_Step12_Middleware