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

With no annotations, the description must carry the full burden of behavioral disclosure. It only states that the body is discarded, implying a status-only response, but fails to mention whether the operation is read-only, what side effects occur, any authentication requirements, or error behavior. The mention of 'discarded after the call' for many parameters suggests no persistent state, but this is not explicitly summarized for the tool as a whole.

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 that clearly states the core action and a key behavioral trait. There is no fluff or repetition. However, it omits any mention of the 9 parameters, which is a structural gap given their diversity; still, the sentence itself is concise and direct.

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 tool has 9 optional parameters and no required ones, making parameter selection ambiguous. The description does not explain how the parameters relate to the stated purpose (e.g., that 'url' is the primary input), nor does it specify the return format beyond 'HTTP status'. With no output schema and no annotations, the description is insufficient for an agent to confidently invoke the tool with the correct parameter.

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 every parameter has a description. The tool description adds no parameter-level context beyond what the schema already provides, nor does it clarify which parameter (likely 'url') is relevant to the stated purpose. The baseline of 3 applies because the schema fully documents each field, but the description fails to map the broad parameter list to the tool's narrow stated function.

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 action ('HTTP status for a public library docs URL') and a behavioral detail ('Body discarded'). However, the input schema contains 9 diverse parameters (city, zone, json, feed, etc.) unrelated to a docs URL, creating ambiguity about what the tool actually operates on. It doesn't distinguish itself from sibling tools like fetch-status or browser-url-ok, which also handle URL status checks.

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 provided on when to use this tool versus alternatives. Siblings such as fetch-status, browser-url-ok, and web-fetch all overlap with URL status checks, but the description never mentions them or states selection criteria. The agent is left to infer usage from the narrow description, which conflicts with the broad parameter set.

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