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

With no annotations, the description carries the full burden of behavior disclosure. It only notes that the title is discarded, but omits whether a network request is made, whether the operation is read-only, and what a successful or unsuccessful result looks like.

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 brief and contains no filler words. However, the second sentence adds only a narrow privacy detail and does not address critical operational information.

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 no annotations and no output schema, this description is far too sparse. It fails to state which parameter to pass, what the return value is, or when to prefer this tool over siblings, leaving agents without essential call information.

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 never identifies which schema parameter receives the Wikipedia title. The eight generic string parameters (ref, url, city, feed, host, json, path, query) all have unrelated descriptions, and none maps to a 'title'. An agent cannot determine how to populate the call, making the high schema coverage irrelevant.

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 uses a specific verb ('Check') and a clear resource ('whether a Wikipedia title exists'). It unambiguously distinguishes this tool from sibling validators that check URLs, file paths, or shapes.

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 offers no guidance on when to use this tool versus sibling validation tools. There are no mention of alternatives, exclusions, or context in which this check should be selected.

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