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

No annotations are provided, so the description carries the full burden. It only discloses that the title is 'discarded after the call,' implying data is not retained, but says nothing about side effects, network usage, read-only nature, or what happens when the title does not exist. The description also does not clarify how the tool behaves given the mismatched schema parameters. This is insufficient for a 9-parameter tool.

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 a single, concise sentence with no fluff. It states the core action and a note about data handling. It is appropriately sized and front-loaded, though its brevity comes at the cost of completeness.

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?

Given the tool's complexity (9 parameters, no required fields, no output schema, no annotations), the description is grossly insufficient. It does not explain how to specify a title, what the return value indicates, or how the tool interacts with the listed parameters. The mismatch between the description and schema makes it nearly impossible for an agent to use correctly. This is a serious gap for a tool with this many inputs.

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 description coverage is 100% (each parameter has a description), giving a baseline of 3. However, the tool description adds no meaning beyond the schema and does not clarify which parameter corresponds to the Wikipedia title. The parameter descriptions are generic (e.g., 'Git ref name; discarded after the shape check') and do not align with the stated purpose. The agent is left without guidance on how to supply the title, so the description fails to compensate for the schema's ambiguity.

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 action and resource: 'Check whether a Wikipedia title exists.' However, the input schema has no parameter for a Wikipedia title (no 'title' field), making it unclear how to invoke the tool. The schema contains unrelated parameters like ref, url, city, feed, etc., so the agent cannot map the stated purpose to the actual inputs. This undermines clarity even though the intent is explicit.

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 on when to use this tool versus alternatives. Sibling tools like browser-url-ok, file-path-ok, and jira-key-shape suggest a family of shape/validity checkers, but no distinctions are drawn. There is no mention of prerequisites, alternatives, or exclusions.

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