more instructions

Author: kentcdodds

exercises/02.tools/FINISHED.mdx

@@ -7,4 +7,5 @@ interactive, AI-powered systems that can do real work for users.
 With these skills, you can create all sorts of tools—calculators, data fetchers,
 workflow automators, and more. The possibilities are wide open!
 
-Keep going—there's a lot more to explore and build!
+Keep going—there's a lot more to explore and build! We're going to take tools a
+little further.

exercises/03.advanced-tools/01.problem.db/README.mdx

@@ -1 +1,15 @@
 # Database
+
+👨‍💼 Our users played around with our Math MCP server and it was fun, but they
+actually want to write journal entries with their LLM. So let's get
+our journaling app ready to store real data! In this step, you'll:
+
+- Import and initialize the database for EpicMe.
+- Make sure your server is set up to use the database instance.
+
+For this first tool, we're just going to allow users to create tags for their
+journal entries. The code comments should guide you through the steps of
+changing our math tool to a `create_tag` tool.
+
+This will lay the groundwork for tools that can create and manage journal tags
+and entries.

exercises/03.advanced-tools/01.solution.db/README.mdx

@@ -1 +1,18 @@
 # Database
+
+👨‍💼 Database is ready! Our users are now happily creating tags! Now your EpicMe
+app can store and retrieve real journal data, setting the foundation for all the
+features to come.
+
+Key takeaways:
+
+- You connected your MCP server to a persistent database, moving beyond
+  in-memory or static data.
+- This unlocks the ability to build tools that interact with real user
+  content—an essential step for any practical application.
+
+<callout-success>
+	The specifics of what happens in your callbacks is up to you!
+</callout-success>
+
+Onward to building and exposing real journaling tools!

exercises/03.advanced-tools/04.problem.errors/README.mdx

@@ -1 +1,21 @@
 # Error Handling
+
+Example error response:
+
+```json
+{
+	"jsonrpc": "2.0",
+	"id": 2,
+	"result": {
+		"content": [
+			{
+				"type": "text",
+				"text": "Entry with id 123 not found"
+			}
+		],
+		"isError": true
+	}
+}
+```
+
+- [📜 MCP Spec: Errors](https://modelcontextprotocol.io/specification/2025-03-26/server/tools#error-handling)

exercises/03.advanced-tools/README.mdx

@@ -1 +1,32 @@
 # Advanced Tools
+
+In the previous exercise, you learned how to register simple tools and handle
+arguments using the Model Context Protocol (MCP). Now, you'll take things to the
+next level by building more realistic, stateful, and robust tools—tools that
+interact with a database, handle errors gracefully, and are organized for
+maintainability.
+
+In this exercise, you'll work on a journaling app called **EpicMe**. The app
+allows users to create and manage journal entries and tags. You'll expose these
+capabilities to clients through MCP tools, making it possible for users (and
+LLMs) to create tags, associate them with entries, and more—all through a
+standardized protocol.
+
+Here's what you'll encounter as you progress:
+
+- **Database Integration:** Instead of just returning static or computed values,
+  your tools will now interact with a real database. This means you'll be able
+  to persist and retrieve data, making your tools much more powerful and useful.
+- **Code Organization:** You'll refactor your code to keep tool definitions a
+  bit more organized, moving them into a dedicated module.
+- **Class-based Server Structure:** You'll encapsulate your server and database
+  logic in a class, preparing things for using Cloudflare's Durable Objects
+  (my personal favorite way to build remote MCP servers).
+- **Robust Error Handling:** You'll add error handling to your tools, ensuring
+  that clients receive clear feedback when something goes wrong, and that errors
+  are surfaced in a way that's compatible with the MCP spec.
+
+By the end of this exercise, you'll have a solid foundation for building
+advanced, production-ready MCP tools that can power real applications.
+
+- 📜 [MCP Spec: Tools](https://modelcontextprotocol.io/specification/2025-03-26/server/tools)