The whole application

`dotnet new koan-web` created exactly these three files.

var builder = WebApplication.CreateBuilder(args);

// bootstraps the framework and composes every capability you referenced
builder.Services.AddKoan();

var app = builder.Build();
await app.RunAsync();

// the entire model. no table, no context, no mapping.
public sealed class Todo : Entity<Todo>
{
    public string Title { get; set; } = "";   // still just business
    public bool Done { get; set; }
}

[Route("api/todos")]
public sealed class TodosController : EntityController<Todo>;
// one declaration. CRUD, paging, queries and streaming project onto api/todos.

Two NuGet references, three files - and api/todos persists, queries and survives restarts. Storage here is local SQLite; the day the app outgrows it, remove that reference and add another adapter. The code above does not change.

Search by meaning

The generated project already carries Koan's agent skills. Want AI on your todos? Ask:

$koan add semantic search for Todo

+ [Embedding(Template = "{Title}. {Notes}")]   // saves index meaning, locally
  public sealed class Todo : Entity<Todo>;

- public sealed class TodosController : EntityController<Todo>;
+ public sealed class TodosController : EntityController<Todo>
+ {
+     [HttpGet("search")]   // the controller you already have learns a verb
+     public async Task<IActionResult> Find(string q, CancellationToken ct)
+         => Ok(await Vector<Todo>.Search(await Koan.AI.Client.Embed(q, ct), topK: 10));
+ }

Presto - "something quick before the game" now finds the right chores. Computed entirely on your machine; no service, no key.

Pictures

$koan add photo uploads, and give me a little gallery page

+ using Koan.Media;
+
+ public sealed class Photo : MediaEntity<Photo>
+ {
+     public string AlbumId { get; set; } = "";   // metadata beside your other entities
+ }
+
+ [Route("api/photos")]
+ public sealed class PhotosController : EntityController<Photo>;   // uploads, listing, serving
+
+ // plus Pages/Gallery.cshtml - a small uploads-and-grid page, ordinary ASP.NET Core

Originals land in storage, resized cards render on demand, identical files dedupe. UI was never the framework's job; capabilities were.

Let agents in

+ [McpEntity(Name = "todo", Description = "Work the team intends to finish")]
  public sealed class Todo : Entity<Todo>;   // same todo. now agents see it too.

Claude works these todos under the same rules your API enforces. Same model, every doorway.