agent-framework/dotnet/samples/04-hosting/FoundryHostedAgents/responses/Hosted-Workflow-Handoff

Hosted-Workflow-Handoff

A hosted agent server demonstrating two patterns in a single app:

• tool-agent — an agent with local tools (time, weather) plus remote Microsoft Learn MCP tools
• triage-workflow — a handoff workflow that routes conversations to specialist agents (code expert or creative writer) using AgentWorkflowBuilder

Both agents are served over the Responses protocol. The server also exposes interactive web demos at /tool-demo and /workflow-demo.

Unlike the other samples in this folder, this one connects to an Azure OpenAI resource directly (not an Azure AI Foundry project endpoint).

Prerequisites

• .NET 10 SDK
• An Azure OpenAI resource with a deployed model (e.g., gpt-4o)
• Azure CLI logged in (az login)

Configuration

Copy the template and fill in your values:

cp .env.example .env

Edit .env:

AZURE_OPENAI_ENDPOINT=https://<your-account>.openai.azure.com/
AZURE_OPENAI_DEPLOYMENT=gpt-4o
AZURE_BEARER_TOKEN=DefaultAzureCredential
ASPNETCORE_URLS=http://+:8088
ASPNETCORE_ENVIRONMENT=Development

AZURE_BEARER_TOKEN=DefaultAzureCredential is a sentinel value that tells the app to skip the bearer token and fall through to DefaultAzureCredential (requires az login). Set it to a real token only when running in Docker.

Note: .env is gitignored. The .env.example template is checked in as a reference.

Running directly (contributors)

cd dotnet/samples/04-hosting/FoundryHostedAgents/responses/Hosted-Workflow-Handoff
dotnet run

The server starts on http://localhost:8088. Open http://localhost:8088 to see the demo index page.

Test it

Using the Azure Developer CLI (invokes triage-workflow — the primary/default agent):

azd ai agent invoke --local "Write me a short poem about coding"

To target a specific agent by name, use curl:

# Invoke triage-workflow explicitly
curl -X POST http://localhost:8088/responses \
  -H "Content-Type: application/json" \
  -d '{"input": "Write me a haiku about autumn", "model": "triage-workflow"}'

# Invoke tool-agent (local tools + MCP)
curl -X POST http://localhost:8088/responses \
  -H "Content-Type: application/json" \
  -d '{"input": "What time is it in Tokyo?", "model": "tool-agent"}'

Running with Docker

1. Publish for the container runtime

dotnet publish -c Debug -f net10.0 -r linux-musl-x64 --self-contained false -o out

2. Build the Docker image

docker build -f Dockerfile.contributor -t hosted-workflow-handoff .

3. Run the container

export AZURE_BEARER_TOKEN=$(az account get-access-token --resource https://ai.azure.com --query accessToken -o tsv)

docker run --rm -p 8088:8088 \
  -e AZURE_BEARER_TOKEN=$AZURE_BEARER_TOKEN \
  --env-file .env \
  hosted-workflow-handoff

4. Test it

azd ai agent invoke --local "Explain async/await in C#"

How the triage workflow works

User message
     │
     ▼
┌──────────────┐
│ Triage Agent │  ──routes──▶  ┌─────────────┐
│  (router)    │               │ Code Expert │
└──────────────┘               └─────────────┘
     ▲                                │
     │◀──────────────────────────────┘
     │
     └──routes──▶  ┌─────────────────┐
                   │ Creative Writer │
                   └─────────────────┘

The triage agent receives every message and hands off to the appropriate specialist. Specialists route back to the triage agent after responding, allowing for multi-turn conversations.

NuGet package users

Use the standard Dockerfile instead of Dockerfile.contributor. See the commented section in HostedWorkflowHandoff.csproj for the PackageReference alternative.