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

The description adds a useful behavioral caveat: 'Page content is not stored.' With no annotations present, this helps signal a privacy-safe read operation. However, it does not disclose whether the tool performs a live network request, follows redirects, or how failures are handled.

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?

Two short sentences with no filler. The core purpose is front-loaded, and the second sentence earns its place by adding a meaningful non-storage guarantee.

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 no output schema and no annotations, the description is mostly sufficient for a simple URL metadata lookup: it names the inputs and the three return fields. Yet the unusually broad parameter list and the crowded sibling set leave real gaps about parameter selection, failure modes, and output formatting.

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 high, so the baseline is 3 even without param details in the description. The description mentions 'URL' and the output fields, but it does not clarify how the many other schema parameters (ref, city, feed, json, path, host) relate to the core URL behavior or why they are accepted.

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: it returns host, scheme, and HTTP status for a URL. This is clear enough to distinguish it from many siblings, though it doesn't differentiate it from closely related tools like fetch-status or normalize-url.

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 about when to use this tool versus fetch-status, browser-url-ok, normalize-url, or other siblings. The description implies URL-checking use, but it never states conditions, exclusions, or alternatives.

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