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

With no annotations, the description carries the disclosure burden. 'Check whether' implies read-only behavior and 'Title discarded after the call' adds a meaningful retention/state fact. However, it does not explain network behavior, error handling, or what counts as an existing title.

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 concise sentences with the core purpose front-loaded and no filler. The discard note provides useful behavioral detail in minimal space.

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?

The output schema documents the return shape, but the main calling convention is unresolved: the input schema lacks a parameter for the Wikipedia title. Combined with the missing usage guidance, an agent cannot safely invoke this tool.

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?

The input schema has detailed descriptions for seven parameters, but none of them is a Wikipedia title. The description's central concept is not mapped to any parameter, so an agent cannot determine which field supplies the title to check.

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 clearly states a specific operation and resource: checking whether a Wikipedia title exists. It is distinguishable from sibling shape/url-check tools by its unique subject, though it does not explicitly name an alternative.

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?

There is no guidance about when to use this tool versus the many sibling checking tools, nor any conditions or exclusions. 'Title discarded after the call' is a data-handling note, not usage context.

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