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

With no annotations, the description carries the behavioral disclosure burden. It does disclose a key non-obvious behavior: the response body is discarded. However, it does not mention redirect handling, error behavior, rate limits, or output format, so transparency is only 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 core result and followed by the important caveat. No filler or redundant rephrasing.

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 tool exposes 9 optional parameters, no required fields, no output schema, and no annotations, so a two-sentence description is insufficient. It omits which parameters actually trigger the fetch, what the result object looks like, and how this relates to the many URL/status sibling tools.

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 even without parameter details in the description. The description adds only the 'public URL' scope and does not help clarify which of the 9 optional parameters is relevant or why many unrelated parameters exist.

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 tool reports HTTP status and content type for a public URL and that the body is discarded. This gives a concrete outcome and resource, though it lacks an explicit verb and does not explicitly contrast with sibling tools like fetch-status.

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?

'Public URL' and 'Body discarded' imply it is for lightweight status/content-type checks rather than retrieving content, but no alternative tools or explicit when/when-not conditions are named. With siblings like fetch-status and browser-url-ok present, this is a missed routing opportunity.

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