Building Console Apps

Get a console CLI running in under 2 minutes

HPD-Agent works natively in .NET console applications with no additional dependencies. Use await foreach to consume events and build interactive command-line tools.

Quick Start

1. Install the Package

dotnet add package HPD.Agent

2. Create a Minimal Console App

using HPD.Agent;
using HPD.Agent.Events;

// Configure the agent
var agent = new AgentBuilder()
    .WithProvider("anthropic", "claude-sonnet-4-5")
    .WithSystemInstructions("You are a helpful assistant.")
    .Build();

// Start conversation
var messages = new List<ChatMessage>();

while (true)
{
    // Get user input
    Console.Write("You: ");
    var input = Console.ReadLine();
    if (string.IsNullOrEmpty(input)) break;

    messages.Add(new ChatMessage { Role = "user", Content = input });

    // Stream agent response
    Console.Write("Agent: ");
    await foreach (var evt in agent.RunAsync(messages))
    {
        switch (evt)
        {
            case TextDeltaEvent delta:
                Console.Write(delta.Text);
                break;

            case MessageTurnFinishedEvent:
                Console.WriteLine("\n");
                break;
        }
    }
}

3. Run It

dotnet run

That's it! You now have a working console agent.

Next Steps

This basic example gets you started, but production console apps need:

• Tool execution indicators
• Permission prompts
• Error handling
• Ctrl+C cancellation
• Multi-turn conversation management

For complete patterns and best practices, see:

• Event Handling - Understanding the event stream
• Middleware - Adding hooks and custom logic
• Bidirectional Events - Handling user prompts and clarifications
• Streaming & Cancellation - Ctrl+C handling and graceful shutdown

See Also

• Event Handling - Understanding the event stream
• Building Web Apps - SSE streaming for web/mobile