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

With no annotations, the description carries the transparency burden. It discloses a key behavioral trait: the response body is discarded, so the agent will not receive page content. It also scopes the operation to public URLs, implying no auth, and the operation appears side-effect-free; however, it doesn't mention redirects, timeouts, or error handling.

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 with zero filler. The main result is stated first, and the important body-discarded constraint is placed second.

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 description is adequate for a simple status/content-type fetch, but given nine optional parameters and no output schema, it should clarify how the URL parameter relates to the others. It also lacks usage context relative to the many sibling tools, leaving the agent to infer selection and invocation.

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; each parameter has a description. The tool description adds no parameter-level meaning, and it does not clarify which of the nine optional fields is the intended 'public URL' input, though the schema's 'url' field is reasonably discoverable.

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 returns HTTP status and content type for a public URL, and explicitly notes the body is discarded, which helps distinguish it from fetch tools that return content. It does not name sibling tools, and the resource/scope is not elaborated beyond 'public URL', so it stops short of full differentiation.

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 web-fetch versus siblings such as fetch-status, browser-url-ok, or normalize-url. The only implicit signal is 'Body discarded', which hints it is not for content retrieval, but no exclusions or alternatives are stated.

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