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 only states that query and fragment are dropped, but says nothing about error handling, response format, or how the nine input parameters relate to the operation. The presence of unrelated parameters (city, json, zone) is unexplained, creating confusion about actual behavior.

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 efficient sentence that front-loads the core action and the dropping behavior. It earns its place, though it sacrifices completeness for brevity. No fluff or repetition.

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 nine parameters, no annotations, and no output schema, the description is severely inadequate. It does not explain return structure, which parameters are used, error behavior, or how to distinguish it from similar tools. An agent cannot reliably decide when to call it or interpret its results.

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% (every parameter has a description), so the baseline is 3. However, the tool description adds nothing about parameters and fails to clarify that only 'url' is relevant; it does not even mention the other parameters or that they are ignored. The mismatch between the description and the schema actively undermines correct usage.

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 clear verb ('Return'), a specific resource ('origin, host, and path for a URL'), and a precise behavior ('Query and fragment are dropped'). It is unambiguous and distinguishes the tool's core function from generic URL helpers, though it does not name a sibling alternative.

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?

The description gives no guidance on when to use this tool versus the many URL-related siblings (e.g., browser-url-ok, github-repo-shape). No context, prerequisites, or exclusions are provided, leaving the agent to guess based on name alone.

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