Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations are empty, so the description carries the burden. It adds one useful behavioral detail in 'Title discarded after the call', but it does not disclose network behavior, error cases, or the shape of the result. No contradiction with the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences, front-loaded with the purpose and followed by a concise retention note. There is no filler or redundant content.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description should at least imply the return value clearly and show how to supply the title. It does neither, and the disconnect between the description and the input schema leaves an agent unable to invoke the tool reliably.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

While the input schema has roughly 100% parameter descriptions, the description refers to a 'title' that is not present as a schema property. The actual properties (ref, url, city, feed, host, json, path) appear unrelated to a Wikipedia title check, so the description misleads rather than adds meaningful parameter semantics.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a concrete action and resource: 'Check whether a Wikipedia title exists.' This is clear and specific enough to convey the tool's core job. However, it does not distinguish itself from sibling validation tools such as validate-json or browser-url-ok, so it does not earn a 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance about when to use this tool versus alternatives, no context, and no exclusions. With many similar-looking sibling tools, an agent is given no routing cues to choose this one.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.