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

No annotations exist, so the description carries the full burden. It discloses that the body is discarded and the status/type are returned, but it does not mention that other parameters (city, feed, json, zone, etc.) are also 'discarded' as per the schema. This creates a mismatch: the description suggests only URL-related behavior, while the broad parameter list implies additional side effects or validation. The absence of error-handling, timeout, redirect, or auth details is a gap, but the contradictory implication about other parameters is a more serious transparency issue.

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 a single, front-loaded sentence with no filler. It immediately states the core purpose and the key behavioral trait (body discard). Every word earns its place, and the structure is optimally concise.

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 9 parameters, no output schema, no annotations, and many sibling tools, this description is incomplete. It does not explain why there are so many seemingly unrelated parameters, nor what the exact return structure is beyond 'status and content type' (no JSON shape). It also lacks routing guidance among a large family of fetch/check tools. An agent would have to inspect all parameter descriptions and possibly test to fully understand the tool's actual behavior.

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 coverage is 100%, so each of the 9 parameters already has a descriptive text in the schema. The tool description adds only the notion of 'public URL' which slightly enhances the URL parameter, but it does not clarify the role of the other parameters (which are described as discarded). Given the schema carries the heavy lifting, a baseline of 3 is appropriate; the brief description does not meaningfully add to the parameter semantics.

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 exactly what the tool does: fetch a URL and return HTTP status and content type, with the body discarded. It is a specific verb-resource combination that clearly separates it from tools that return full content (like browser-url-ok or playwright-url-ok). The explicit 'Body discarded' resolves ambiguity immediately.

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 description notes 'public URL' which implies a use case, but it does not explicitly say when to choose this tool over sibling tools such as fetch-status, normalize-url, or browser-url-ok. No direct comparison or exclusion is given, so the agent must infer that this is a lightweight status check rather than a full fetch or validation tool.

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