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

No annotations are provided, so the description carries the full burden. It accurately discloses that query and fragment are dropped, which is useful behavioral context. However, it does not disclose whether the tool validates the URL, what happens for invalid URLs, whether the host and path are normalized in specific ways (e.g., case, default ports), or why unrelated parameters (json, zone) exist—leaving significant behavioral 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 a single, tightly worded sentence that front-loads the primary action and result. Every word earns its place, and the dropped query/fragment detail is a concise, valuable behavioral note without padding.

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 that appears to normalize URLs, the description is too terse: it lacks details on input validation, error handling, output format (though no output schema exists), and the role of the three extra parameters. The presence of unrelated parameters and zero required parameters suggests the tool may have multiple modes, but nothing in the description disambiguates this, making it incomplete for reliable invocation.

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 schema already documents all four parameters. The description adds no extra meaning for parameters beyond 'url'—it doesn't clarify how 'host', 'json', and 'zone' relate to the stated purpose of returning origin/host/path. With full schema coverage, baseline 3 is appropriate, but the mismatch between the description's focus and the schema's parameter set is not compensated.

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 ('Return') and resource ('origin, host, and path for a URL') and clearly distinguishes the tool's scope by noting that query and fragment are dropped. However, it does not name sibling tools or explicitly differentiate from alternatives, and the schema's other parameters (host, json, zone) are not accounted for in this purpose statement.

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 a usage context: given a URL, extract the origin, host, and path. There is no guidance on when to use this versus alternatives (e.g., a full URL parser or a citation tool), and the schema includes unrelated parameters (json, zone) that suggest other potential uses, creating confusion about when to invoke this tool.

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