AI features are easiest to ship when the .NET application is already shaped like a production system: clear boundaries, testable services, observable endpoints, and deployment-friendly configuration. In this tutorial, we will build the foundation for an AI-ready ASP.NET Core API without locking the project to one model provider.
Why AI-Ready Architecture Matters
Many teams start by calling an AI API directly from a controller. That works for a demo, but it becomes painful when you need retries, prompt versioning, audit logs, safety checks, caching, or provider changes. A better approach is to isolate the AI workflow behind an application service and keep the HTTP layer thin.
Project Shape
A practical starting structure looks like this:
src/
Api/
Program.cs
Endpoints/
Application/
Ai/
IAiAssistant.cs
AiAssistant.cs
Infrastructure/
Ai/
AiClientOptions.cs
HttpAiClient.cs
Domain/
KnowledgeAnswer.cs
The API project handles routing. The application layer owns business use cases. The infrastructure layer talks to external AI providers. This keeps your C# code clean even as the AI implementation changes.
Create a Thin Endpoint
Minimal APIs are a good fit for focused AI workflows. The endpoint validates input, calls the application service, and returns a result.
app.MapPost("/api/assistant/answer", async (
AskQuestionRequest request,
IAiAssistant assistant,
CancellationToken cancellationToken) =>
{
if (string.IsNullOrWhiteSpace(request.Question))
{
return Results.BadRequest("Question is required.");
}
var answer = await assistant.AnswerAsync(
request.Question,
cancellationToken);
return Results.Ok(answer);
});
public sealed record AskQuestionRequest(string Question);
Hide Provider Details Behind an Interface
The application should not care whether the answer comes from OpenAI, Azure OpenAI, Amazon Bedrock, a local model, or a future internal gateway.
public interface IAiAssistant
{
Task<KnowledgeAnswer> AnswerAsync(
string question,
CancellationToken cancellationToken);
}
public sealed class AiAssistant : IAiAssistant
{
private readonly IAiClient _client;
public AiAssistant(IAiClient client)
{
_client = client;
}
public async Task<KnowledgeAnswer> AnswerAsync(
string question,
CancellationToken cancellationToken)
{
var prompt = $"Answer this developer question clearly: {question}";
var response = await _client.GenerateAsync(prompt, cancellationToken);
return new KnowledgeAnswer(
response.Text,
DateTimeOffset.UtcNow);
}
}
Add Docker-Friendly Configuration
AI applications should never hard-code keys or deployment settings. Use environment variables locally, in Docker, Kubernetes, and AWS.
builder.Services.Configure<AiClientOptions>(
builder.Configuration.GetSection("AiClient"));
builder.Services.AddHttpClient<IAiClient, HttpAiClient>();
builder.Services.AddScoped<IAiAssistant, AiAssistant>();
Example Docker environment variables:
AIClient__Endpoint=https://api.example.com/v1/chat
AIClient__ApiKey=replace-with-secret-manager-value
ASPNETCORE_ENVIRONMENT=Production
Production Checklist
- Add request and response logging, but avoid storing sensitive user data.
- Use timeouts and retries for external AI calls.
- Validate user input before sending it to a model.
- Store prompts in versioned files or database records.
- Use Docker health checks for container orchestration.
- Move secrets to AWS Secrets Manager, Parameter Store, or your platform equivalent.
- Add integration tests around the application service, not only the controller.
Where Kubernetes and AWS Fit
Once the API is containerized, Kubernetes can scale the service horizontally while AWS handles secrets, networking, observability, and managed hosting. The important part is that the .NET API remains provider-neutral. Your deployment platform should not leak into the core application design.
Final Thoughts
An AI-ready .NET API is not just an API that calls a model. It is a system that can evolve safely. Keep controllers thin, isolate AI provider details, configure through environment variables, and make Docker deployment part of the design from day one.