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

With no annotations, the description carries the full burden. It only says 'Title discarded after the call,' which is vague and does not explain the tool's overall behavior, side effects, error handling, or what happens with the other parameters. The mention of a discarded title is confusing since no title parameter exists.

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?

The description is extremely short, which is concise, but it is under-specified. The two sentences do not earn their place because they omit essential information about how to use the tool. There is no front-loaded critical guidance beyond a misleading purpose.

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?

For a tool with 9 optional parameters, no output schema, and no annotations, the description is wholly inadequate. It does not explain the tool's role, how the parameters interact, what the tool returns, or any constraints. An agent has no basis for correct invocation.

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 description adds no meaning to any parameter. The schema descriptions are present (100% coverage) but they are generic and unrelated to the stated purpose, e.g., 'Git ref name; discarded after the shape check.' The description does not tie these parameters to Wikipedia title checking, so it provides no additional value.

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 clear verb and resource: 'Check whether a Wikipedia title exists.' However, the input schema contains no title parameter—instead it lists unrelated fields like ref, url, city, and json. This makes the stated purpose misleading and inconsistent with the actual interface, so an agent cannot reliably determine what this tool does.

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?

No guidance is given for when to use this tool versus the many sibling tools (e.g., browser-url-ok, fetch-status, normalize-url). There is no mention of context, exclusions, or alternatives, leaving the agent to guess when this tool is appropriate.

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