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

With no annotations at all, the full burden of describing behavior falls on the description. It discloses only that the title is discarded, and it does not mention any side effects, external requests, status responses, or correctness edge cases. The mention of 'title' is also suspicious because no title parameter exists in the schema.

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 short and front-loaded: two sentences with no filler. However, the second sentence about discarding a title is of limited value because 'title' is not an explicit input; the brevity, despite genuinely concise, is not enough to make the tool callable.

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 annotations, no output schema, no required parameters, and nine optional fields, the description should provide clarity on how to call the tool, what input carries the title, and what the result looks like. It provides none of that, leaving the tool effectively unusable for an agent.

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?

Schema descriptions already cover 100% of parameters, giving a baseline of 3, but the description adds no useful param guidance. Worse, it introduces a 'title' concept that is absent from the nine-parameter schema, so the agent cannot map the requested Wikipedia title to any actual parameter.

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 sentence 'Check whether a Wikipedia title exists' states a concrete verb, resource, and action, and it distinguishes this tool from sibling validators like fetch-url's or domain-shape. Some clarity is lost because the input schema contains no 'title' property, but the high-level purpose itself is clear.

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 instead of a sibling such as browser-url-ok, fetch-domain, domain-shape, or search-query-len. No prerequisites, alternatives, or exclusion conditions are mentioned, so agents get no support for tool selection.

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