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

No annotations are provided, so the description carries the full behavioral burden. It discloses one useful trait—'Title discarded after the call'—but says nothing about read-only behavior, network access, error handling, or the shape of the response, leaving the agent under-informed about side effects and expectations.

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 very short, front-loaded with the main purpose, and the retention caveat is useful and non-redundant. It lacks more detailed structure, but as far as conciseness goes, every word earns its place.

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 7-parameter tool with no annotations and no output schema, this description is severely incomplete. The necessary input is ambiguous, the expected return value is undocumented, and the behavior beyond 'title discarded' is unexplained, so the agent would be guessing at correct usage.

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 the schema descriptions cover 100% of the parameters, none of them maps to a Wikipedia title: ref is a Git ref, url/feed/host are network strings, json is JSON text, and path is a file path. The description does not explain which field carries the title, so an agent cannot reliably invoke this tool correctly.

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 clearly states the operation ('Check whether') and the resource ('a Wikipedia title'), so an agent can tell what the tool does. It does not connect this purpose to any specific input parameter or distinguish itself from sibling validation tools, so it falls just short of a 5.

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 about when to use this tool versus alternatives such as normalize-url, fetch-status, or validate-json. The only usage signal is implicit in the name and phrase 'Check whether a Wikipedia title exists,' with no when-not-to-use conditions or alternative routing.

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