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

With no annotations, the description carries the behavioral transparency burden. It clearly discloses the key behavior that the body is discarded and only HTTP status and content type are returned. This corrects a common assumption about a 'web-fetch' tool, though it does not address redirects, timeouts, or error behavior.

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 with no filler. The primary purpose is stated first, and the important body-discard caveat is stated second, making it efficient and front-loaded.

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?

Despite a large sibling list and a nine-parameter schema with no output schema or annotations, the description gives only a one-line overview. It does not explain how the non-URL parameters relate to the tool, what the return structure looks like, or how this tool differs from closely related siblings.

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 tool description itself adds no parameter-level detail. Each of the nine parameters already has a meaningful description in the schema; the description adds nothing more about parameters.

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 verb and resource: return HTTP status and content type for a public URL, discarding the body. This is clear at face value, but the input schema exposes nine unrelated parameters such as city, json, zone, and query that the description never mentions or reconciles, making the tool's full scope confusing.

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 explicit guidance about when to use web-fetch versus siblings like fetch-status, normalize-url, browser-url-ok, or inspect-robots. 'Body discarded' implies it is for status/content-type checks rather than content retrieval, but no clear when-to-use or when-not-to-use guidance is provided.

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