# AI Code Exploration Exercise

A small C# application for practicing code exploration with a coding agent: use it to produce diagrams that reveal the structure and behavior of an unfamiliar codebase.

## What this is

`src/Before/` contains a small domain model (Client, Order) with an in-memory `DbContext` and a `WebApp` consumer. `src/Before.Console/` is a demo console app that seeds data and queries it. `tests/Before.Tests/` covers the behavior.

**You do not need to read or understand the code before starting.** The point is to use a coding agent to produce the diagrams.

## Prerequisites

- A coding agent with access to this repo (Claude Code, Cursor, Copilot, etc.)
- .NET SDK 10.0
- `mmdc` CLI for Mermaid rendering, or IDE Mermaid preview

## Setup

1. Clone this repo
2. Open `ai-code-exploration.sln` in your IDE
3. Build to verify everything compiles:
   ```
   dotnet build
   ```

## Tasks

Start broad, then iterate with follow-up prompts to refine.

### Task 1: Class diagram

Create a **class diagram** of the classes in `src/Before/` using Mermaid. Iterate until it captures the structure accurately.

**What to check:** Are the inheritance relationships correct? Are the associations (Client → Orders, Order → Client) visible? Is the dependency between the domain classes and `DbContext` shown — and in which direction does it point?

### Task 2: Sequence diagram — happy path

Create a **sequence diagram** for the flow when `Client.FindByName("Jane Doe")` is called.

### Task 3: Sequence diagram — exception path

Create a **sequence diagram** for `Client.FindByNameRequired("Nobody")` — when the client is not found. What interactions differ from the happy path? Where is `ObjectNotFoundException` thrown?

### Task 4 (stretch): Full initialization flow

From `Program.cs` (the console entry point), trace how the `DbContext` is created and made available to entities, and what interactions happen on `Client` and `Order`. Include the exception flow from Task 3. This will be a larger diagram — iterate and simplify as needed.

## Tips

- **Start broad, then refine:** "Draw me a class diagram of src/Before/" is enough to start.
- **Iterate on the prompt:** If the first diagram is missing something, ask the agent to add it. You don't need to write Mermaid syntax.
- **Validate:** Use `mmdc` to check syntax, visually check the diagram against the code.
- **Direct the agent;** don't write diagrams by hand.