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

With no annotations, the description must carry the behavioral burden. It does disclose the core transformation (dropping query and fragment), but it does not specify behavior for invalid/missing URLs, whether the operation is purely local or performs network access, or return value structure.

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, front-loaded with the main purpose and followed by the key transformation. Every word adds value; no filler or redundant restatement of the tool name.

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?

Given no output schema and no annotations, the description should do more: it should state the return shape, note that only url is needed/used despite nine optional parameters, and clarify constraints such as HTTPS-only or error handling. It is minimally adequate but not 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 coverage is 100%, so a baseline of 3 applies. The description clarifies that url is the parameter of interest and what output it produces, but it does not explain the role of the other eight parameters or explicitly say they are ignored beyond the schema's own 'discarded' notes.

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?

Description states a specific verb ('Return') and resource ('a URL'), and identifies the exact outputs: origin, host, path. Mentioning that query and fragment are dropped differentiates this from URL validation/fetching siblings like browser-url-ok or web-fetch.

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 use when a caller needs URL components with query/fragment stripped, but it never states when to prefer this over sibling tools or which alternatives to avoid. No exclusions or selection criteria are provided.

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