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

Annotations are absent, so the description must carry the full behavioral disclosure. It mentions 'Title discarded after the call,' which is a side-effect note, but it does not explain the primary behavior beyond checking existence, what happens on success/failure, or any security/permission implications. The mismatch between the description mentioning 'title' and the schema lacking a 'title' parameter further reduces transparency.

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 brief (one sentence), which is concise but not structured effectively. It under-specifies critical information like how to provide the title and what the tool returns. The brevity here is a deficiency rather than a virtue, as it omits essential usage details.

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 9 parameters, no annotations, and no output schema, the description is woefully incomplete. It fails to explain which parameter corresponds to the title, how the check is performed, what the response format is, or how it differs from the many sibling tools. The description provides almost no contextual guidance for an agent to invoke it correctly.

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?

Although schema coverage is 100% (all parameters have descriptions), the tool description does not map the concept of 'title' to any specific parameter. The schema lists parameters like 'query', 'ref', 'url' with unrelated descriptions, and none explicitly represents a Wikipedia title. The description adds no value in clarifying which parameter to use for the title, leaving the agent to infer incorrectly.

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 specific verb and resource: 'Check whether a Wikipedia title exists.' This clearly communicates the core function. However, it does not differentiate from siblings like 'normalize-url' or 'fetch-status' which might also handle URLs or titles, so it misses an opportunity for distinction.

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 on when to use this tool versus alternatives. The description does not mention any sibling tools, conditions, or exclusions. An agent is left to guess whether this is the right tool for checking a Wikipedia title versus another tool like 'normalize-url' or 'fetch-status'.

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