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

The description discloses only that the body is discarded. It does not mention network behavior, redirects, error handling, timeouts, read-only guarantees, or what happens when non-URL parameters are provided. With no annotations, this leaves important behavioral aspects undocumented.

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 succinct and front-loaded: 'HTTP status and content type for a public URL. Body discarded.' It contains no redundant wording, though it sacrifices completeness for brevity.

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?

With nine optional parameters, no output schema, and no annotations, the description is highly incomplete. It only addresses URL fetching and body discard, leaving output format, error behavior, and parameter selection completely unexplained.

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?

All parameters have schema descriptions, but the tool description does not explain how they relate to fetching HTTP status/content type. For instance, url is described as 'HTTPS URL to normalize or cite' rather than to fetch, and parameters like zone and query appear entirely unrelated, creating a semantic mismatch between the tool purpose and the schema.

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 identifies a clear resource and outcome—HTTP status and content type for a public URL—and explicitly notes the body is discarded. However, it lacks a direct verb and is undermined by an input schema with nine unrelated optional parameters (e.g., zone, query, json), which makes the actual purpose ambiguous.

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?

No guidance is given about when to use this tool versus sibling tools such as fetch-status, browser-url-ok, normalize-url, or playwright-url-ok. There is also no instruction on which of the nine parameters to supply or how to disambiguate between them.

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