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

With no annotations, the description carries the full behavioral burden. It does add one meaningful disclosure—'Page content is not stored'—which is a useful privacy guarantee. But it does not state whether the URL is fetched, whether redirects are followed, or how failures are handled, leaving behavioral coverage partial.

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 first delivers the action and outputs, the second adds a relevant privacy caveat. It is front-loaded and every sentence earns its place. This is an efficient, well-structured description.

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 core URL use case is clear, but the description is incomplete for confident tool selection: no output schema, no annotations, 9 optional parameters left unexplained, and no mention of error behavior or how this differs from sibling URL/status tools. The many 'discarded' parameters create a real gap between the simple description and the actual input surface.

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?

The schema already documents all 9 parameters with descriptions, so the baseline is 3. The description adds minimal value by identifying the URL as the central input and naming the outputs, but it ignores the many optional parameters and their 'discarded' semantics. It neither significantly enriches nor contradicts 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 action ('Return') and concrete outputs (host, scheme, HTTP status) for a URL, so an agent can tell what the tool computes. However, it does not explicitly distinguish this from siblings like fetch-status or normalize-url, so it stops short of full differentiation.

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 instead of alternatives, no exclusions, and no routing hints. The only implied use case is 'for a URL,' and the storage disclaimer is not a usage condition. An agent cannot reliably choose between citation and similar URL/status tools from this text.

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