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

With no annotations, the description carries the full burden. It discloses that query and fragment are dropped, which is useful, but it does not specify error behavior for invalid URLs, the return format, or that the tool is read-only. The HTTPS constraint appears only in the schema, not in the description, which is a notable gap.

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 concise sentences with zero fluff. The primary behavior is front-loaded, and the dropped components are mentioned immediately. This is an appropriately sized 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 tool has no output schema, so the description must explain the return value, but it only lists the components without specifying structure (e.g., string, object, list). Additionally, the schema includes nine parameters, many irrelevant to the stated purpose, yet the description does not clarify that only 'url' is relevant. This makes the tool confusing to call correctly.

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 no parameter-specific meaning; it does not even mention the 'url' parameter explicitly. However, the schema already documents each parameter, so the description is not required to repeat them. The lack of clarification about which parameters are actually used is a minor omission given the schema covers them.

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 origin, host, and path') on a specific resource (a URL) and clearly notes that query and fragment are dropped. This distinguishes it from sibling tools that validate or check URL shapes, such as browser-url-ok or figma-url-shape.

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 alternatives. It does not mention prerequisites (e.g., HTTPS requirement) or situations where this tool should not be used. Sibling tools like web-fetch or inspect-robots are not referenced, leaving the agent to infer usage from the name alone.

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