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

With no annotations, the description carries the full burden of behavioral disclosure. It discloses one behavior ('Body discarded') but does not explain that most parameters are ignored or what the exact return value is beyond 'HTTP status'. It omits details about error handling, rate limits, or whether the URL is the only meaningful input.

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 brief and front-loaded with the core purpose. Two sentences contain no fluff. However, the brevity comes at the cost of completeness, which is a structural tradeoff but not a failure in conciseness.

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 nine parameters, no output schema, and no annotations. The description provides only a narrow claim (HTTP status for a library docs URL) without explaining how the other parameters are used, what the response structure is, or why the tool exists alongside similar siblings. An agent cannot reliably determine the correct invocation from this description alone.

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 each parameter has its own description in the schema. The tool description adds only a narrowing context ('public library docs URL') that might apply to the 'url' parameter, but it does not clarify how the other eight parameters relate to the stated purpose. This adds marginal value beyond 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 states a specific verb and resource ('HTTP status for a public library docs URL'), which gives a clear primary purpose. However, the input schema includes nine unrelated parameters (city, zone, json, path, etc.) that are not mentioned, creating ambiguity about the tool's actual scope. It also does not differentiate from sibling tools like fetch-status or browser-url-ok, which also check HTTP status.

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 guidance on when to use this tool versus alternatives. It does not mention that it is intended for library docs URLs specifically, nor does it advise using other tools for different URL types. The description lacks any contextual cues for selection among the many sibling tools.

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