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

With no annotations, the description carries the burden of behavioral disclosure. It only states that the title is discarded after the call, which implies no persistence. However, it does not disclose whether the tool makes network requests, requires authentication, or has side effects. The schema descriptions also mention 'discarded' for many fields, but these are generic and do not clarify the tool's overall behavior.

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 (one sentence), which is concise, but it lacks structure and essential information. It does not front-load critical details or explain the tool's workflow. The brevity is under-specification rather than effective conciseness.

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 9 optional parameters, no output schema, and no annotations, the description is severely incomplete. It does not explain the purpose of each parameter, how they contribute to the title check, what the tool returns, or any error conditions. An agent would be unable to invoke this tool correctly based on the description alone.

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 coverage is 100%, so every parameter has a description, but these descriptions are misleading in the context of the tool. For example, 'ref' says 'Git ref name; discarded after the shape check' – this has nothing to do with checking a Wikipedia title. The tool description adds no clarification about how parameters relate to the tool's purpose. An agent cannot infer which parameter, if any, holds the title to check.

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 purpose: 'Check whether a Wikipedia title exists.' This is a clear verb and resource, but it does not map to any of the 9 input parameters (none are named 'title' or obviously represent a Wikipedia title). The schema is filled with unrelated fields (ref, url, city, feed, etc.), so an agent cannot determine how to provide the title. It also does not differentiate from sibling tools that might check URLs or fetch pages.

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 gives no guidance on when to use this tool versus alternatives. There is no mention of prerequisites, exclusions, or related sibling tools. An agent has no context to decide between this and similar checking tools like browser-url-ok or fetch-status.

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