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

With no annotations, the description carries the transparency burden. It discloses one meaningful behavioral trait: page content is not stored. It does not mention network access, redirect handling, failure behavior, or whether the URL is fetched, so transparency is partial.

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?

Two short sentences, front-loaded with the primary behavior, and the storage caveat is a useful addition. There is no wasted text.

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?

The core behavior is clear, but the description is terse relative to the context: nine optional parameters, no annotations, no output schema, and many URL-related sibling tools. It does not clarify which parameter to pass, what the output structure looks like, or how errors are reported.

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 description coverage is 100%, so the baseline is 3. The description adds little parameter-level meaning and does not clarify that the url parameter is the relevant one among nine optional parameters; the schema descriptions do most of the work.

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?

States a specific verb and resource: return host, scheme, and HTTP status for a URL. The note that page content is not stored adds useful scope, but it does not explicitly differentiate from url-related siblings like fetch-status or normalize-url.

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 implies when to use the tool: when an agent needs host, scheme, and HTTP status for a URL without page content. However, it does not name alternatives or provide explicit when-to-use/when-not-to-use guidance, leaving routing mostly to inference.

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