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

The description openly discloses a key behavior: 'Body discarded.' This is useful beyond the tool name, especially because no annotations are present. However, it does not mention status-code semantics, redirect handling, error behavior, timeout behavior, or whether the URL is fetched directly, so the behavioral disclosure 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?

The description is two short sentences, front-loads the primary purpose, and the second sentence adds a non-obvious behavioral detail. There is no redundant wording or restatement of the tool name.

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 nine optional parameters, no annotations, and no output schema, this description is too thin. It does not explain which parameter contains the URL to fetch, why the other parameters exist, what the return payload looks like, or how it relates to sibling fetch/URL tools. An agent is left with a clear purpose but insufficient invocation guidance.

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 though the description adds no parameter-level detail. However, the schema's per-parameter descriptions—such as 'HTTPS URL to normalize or cite'—do not align cleanly with the description's fetch/status/content-type purpose, leaving some confusion about which parameter actually drives the tool.

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 operation: report HTTP status and content type for a public URL, and explicitly notes that the body is discarded. This is a specific resource plus a specific observable outcome. It does not explicitly contrast with siblings like fetch-status or browser-url-ok, but the core intent is unambiguous.

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 phrase 'for a public URL' gives only a minimal scope hint. There is no guidance about when to prefer web-fetch over sibling tools such as fetch-status, normalize-url, browser-url-ok, or playwright-url-ok, and no exclusions are stated. The description does not help an agent choose among overlapping URL-related tools.

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