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

The description discloses a key behavioral trait: query and fragment are intentionally dropped. Since no annotations are provided, the description carries the burden, but it does not mention how invalid URLs are handled, whether the URL must be HTTPS, or that most of the nine schema parameters appear to be ignored.

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 front-loaded sentence that states the output and the key exclusion in a direct, efficient way. There is no unnecessary prose or repetition of schema contents.

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 simple, non-mutating URL utility, the description gives the core behavior, but it lacks an explicit return format and does not address the large number of optional parameters or their relationship to the tool. With no output schema or annotations to fill these gaps, the description is adequate but not fully complete.

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 the baseline is 3. The description adds useful context about the output and that URL query/fragment are removed, but it does not clarify which of the nine parameters are actually relevant or should be provided for normalization.

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 the verb ('Return'), the resource ('a URL'), and the specific outputs ('origin, host, and path'). It also differentiates the behavior from a generic URL fetcher or validity checker by noting that query strings and fragments are dropped.

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 implies this tool should be used when an agent needs a URL decomposed into origin, host, and path while discarding query/fragment. However, it does not explicitly name alternatives or state when not to use this tool versus siblings like browser-url-ok or domain-shape.

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