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

With no annotations, the description carries the burden. It discloses that query and fragment are dropped but does not mention edge cases, error behavior, how the URL is required to be formatted, or that the other 8 schema parameters are discarded. The behavioral disclosure is partial and potentially misleading given the schema's many unrelated parameters.

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 with no filler. It states the core purpose and a key behavioral constraint (query/fragment dropped) efficiently, making it easy for an agent to grasp the essentials.

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 the tool has 9 parameters but no output schema, the brief description is insufficient. It does not explain the result shape, which parameters are actually consumed, or why the schema includes many irrelevant fields. An agent cannot fully understand how to invoke this tool 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 additional semantics for parameters; it simply focuses on the 'url' parameter, while the schema already documents each parameter individually. It does not compensate for or clarify the presence of unrelated parameters.

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 and resource: 'Return origin, host, and path for a URL.' It also notes query and fragment dropping, which distinguishes it from URL-fetching or checking siblings. It is clear but doesn't explicitly differentiate itself from all related tools by name.

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?

No guidance is provided on when to use this tool instead of alternatives like browser-url-ok or web-fetch. There are no conditions, prerequisites, or exclusions. The description only states the output, leaving the selection context entirely implicit.

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