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

Annotations are absent, so the description must carry the full burden. It discloses one behavior ('Page content is not stored') but fails to mention that it likely performs an HTTP request, potential failure modes, rate limits, or how the other parameters (ref, city, feed, etc.) are handled. The schema indicates these are discarded, but the description does not clarify their role or side effects, leaving significant ambiguity.

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 concise at two sentences, but it is under-informative given the complexity of 9 parameters. It front-loads the core function but omits any explanation of the broader parameter set, making it more terse than helpful.

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?

For a tool with 9 optional parameters, no annotations, and no output schema, the description is incomplete. It does not explain the return format beyond naming the fields, does not clarify the purpose of the other parameters, and offers no usage context. An agent would likely be uncertain about how to call this tool correctly.

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?

While schema coverage is 100%, the description only addresses the URL parameter. The other eight parameters have schema descriptions that appear unrelated to the tool's stated purpose (e.g., 'Git ref name; discarded after the shape check'). The description does not reconcile this mismatch or add context for these parameters, so it fails to compensate for the confusion.

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 clearly states a specific verb and resource: 'Return host, scheme, and HTTP status for a URL.' It also adds a clarifying note about not storing page content. However, it does not explicitly differentiate this from siblings like 'fetch-status' or 'normalize-url', so the purpose is clear but not fully distinguished.

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. It does not mention any conditions, prerequisites, or scenarios where this tool is preferred. The note about not storing content hints at a lightweight check but does not explicitly compare to siblings.

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