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

No annotations are present, so the description must carry the full burden. It discloses that the title is 'discarded after the call,' which is a lightweight privacy trait, but it does not explain return behavior, whether external network requests are made, or what 'exists' means. For an existence-checking tool, this is under-specified.

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 two short sentences with no filler, and the operation is front-loaded. However, the second sentence is somewhat redundant with the discard language already echoed in several parameter descriptions.

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 eight parameters, no output schema, and no annotations, the description is far too sparse. It omits the return value, which parameter represents the Wikipedia title, and any caveats about URL forms or alternative tools, making reliable invocation difficult.

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 schema documents all eight parameters, so the baseline is 3, but the description names a 'title' concept that maps to none of the schema parameters. The parameter descriptions (e.g., 'Git ref name,' 'City name for a public weather hint') appear unrelated to Wikipedia titles, so the description does not help the agent choose the correct 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 description states a specific operation: 'Check whether a Wikipedia title exists,' which is clear and distinct from the sibling URL/shape tools. However, the input schema contains no 'title' parameter—only ref, url, city, feed, host, json, and path—so the stated purpose does not map cleanly to a usable input.

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 such as normalize-url, web-fetch, or validate-json. The description gives no prerequisites, exclusions, or contextual conditions for choosing this tool.

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