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

With no annotations, the description carries the full burden of behavioral disclosure. It does reveal that the body is discarded, but it says nothing about network side effects, redirects, timeouts, rate limits, authentication, or the overall response shape beyond 'HTTP status'. This is under-disclosed for a tool that appears to make network requests.

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 two sentences are terse and front-loaded, and every word contributes. However, for a tool exposing nine optional parameters and no output schema, this brevity is under-specification rather than appropriate concision.

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 no output schema, no annotations, and a broad polymorphic-looking schema, the description is far too thin. It explains only a single URL-status behavior and silently leaves the other eight parameters and their behavior unexplained, so an agent cannot confidently call the tool outside the narrow library-docs-url case.

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 describes each parameter, the tool description does not map 'public library docs URL' to the url parameter, whose schema description says 'normalize or cite' rather than 'check HTTP status'. The description also provides no relationship between the nine optional parameters and no indication of which field selects the documented behavior, so the description adds little usable semantic value.

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 output, HTTP status for a public library docs URL, and notes that the body is discarded, which gives a narrow but recognizable purpose. However, it never explicitly says 'returns' or 'gets', does not mention the nine optional parameters, and does not differentiate itself from sibling status/fetch tools like fetch-status or browser-url-ok.

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 instead of fetch-status, web-fetch, normalize-url, or other siblings. No when-not conditions or alternative routing are provided, leaving the agent to infer usage solely from the name and one-sentence description.

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