Read a Resource

Not everything MCP exposes is a tool

In Module 2, you used search_resources. That tool accepted an input, performed a search, and returned a result.

The Practice Resource Desk also exposes something different:

practice://resource-desk/overview

This is a resource. Instead of asking the server to perform a search, you are asking it for a particular piece of information it already makes available.

Tools and resources can both return information. The difference is what you are asking the server to do.

This distinction will matter later when an AI application decides what kind of capability it needs.

Two words to learn

A URI can look like a web address, but it does not have to point to a website.

Step 1 — See what information the server exposes

Start the Inspector and connect to practice-resource-desk exactly as before, then click the Resources tab.

The left column lists what this server exposes, grouped in two sections:

That last point is the one worth pausing on, and the next section explains it.

The URI is not shown in the list. The Inspector lists this resource by its readable name only. Its URI appears once you open it — which, as you are about to see, is the same action as reading it.

Why isn’t there an input box?

In Module 2, the tool needed to know what you wanted to search for. You had to supply citation before Execute Tool would even become clickable.

This resource already has an identity:

practice://resource-desk/overview

You are requesting that particular resource, so there is no search term to supply.

That does not mean every MCP resource is permanently fixed or stored as a file. A server can produce resource content dynamically.

Step 2 — Ask for the resource

Click About the Practice Resource Desk in the list.

Selecting it is the read. There is no separate Read or Fetch button in this version of the Inspector. The moment you click the entry, the Inspector requests the resource and shows you what came back.

A panel headed Resource opens beside the list, with the URI along its top edge:

The content arrives as formatted text — a heading, a paragraph, and a list — because the server sent it that way and the Inspector displays it as written. It begins:

Practice Resource Desk

A fictional service invented for the MCP Without the Mystery tutorial.
It is not a Robert Crown Law Library service, and nothing here describes
a real offering.

Below the content you will see a Refresh control, which asks the server for the resource again, and a View Source control, which swaps the formatted text for the plain characters the server actually sent. Neither is needed for this exercise.

Inspector may also show the resource’s format. You do not need to memorize that label for this exercise.

To close the content and return to the list on its own, click the × beside the word Resource. The list itself never went away.

What happened?

1. You selected a known resource.
2. Inspector requested that resource from the Practice Resource Desk.
3. The server returned its content.
4. Inspector displayed it.

You did not ask the server to search, calculate, edit, or choose anything. You requested information the server had already made available under a URI.

No AI model selected or summarized the resource for you.

Tool or resource?

search_resources

You provide a search term and ask the server to perform a search.

practice://resource-desk/overview

You identify information the server already exposes and ask to read it.

Both can return text. The type of capability tells you what relationship you have with the server — not what the answer happens to look like.

What to notice

A resource is something you can identify before you read it.

Before you requested anything, you knew this resource by name and knew the kind of information it represented. The server had already announced it. And the resource carries a URI — a stable identifier — so it can be named and requested deliberately rather than stumbled upon.

A tool asks the server to perform defined work. A resource asks the server for identified information it exposes.

Later, an AI application may use both in the same workflow.

Checkpoint

You are ready for Module 4 if you can:

• explain an MCP resource without calling it a tool;
• identify the overview resource by its URI;
• explain why the URI is not necessarily a webpage;
• read the resource through Inspector;
• distinguish requesting information from invoking a search tool; and
• explain why a resource does not have to be a file.