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

With no annotations, the description must fully disclose behavior. It does reveal that query and fragment are dropped, which is useful, but it does not mention side effects, safety, or how the other eight schema parameters are handled (though some schema descriptions say they are discarded). It also does not state whether the operation is read-only or what happens with invalid URLs. The description is not misleading, but it is incomplete for a tool with no annotation coverage.

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, focused sentence that front-loads the core purpose and includes a key behavioral detail. There is no redundancy or unnecessary wording. It is optimally concise.

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 description is insufficient for a tool with nine parameters, many of which appear unrelated to URL normalization. It does not explain how those parameters are used or ignored, nor does it specify the return format (e.g., object structure). With no output schema, an agent lacks critical information about the expected result. It also does not differentiate from many similar sibling tools, leaving the agent uncertain about when to select it.

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?

The description adds behavioral context for the url parameter (dropping query and fragment), which goes beyond the schema's description of the parameter. However, it does not address the other eight parameters, which all have schema descriptions (some stating they are discarded). Since schema coverage is 100%, the description's added value is modest; it clarifies the main parameter's behavior but not the role of others. Baseline 3 is appropriate.

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 a specific verb ('Return') and resource ('origin, host, and path for a URL'), and explicitly notes that query and fragment are dropped. This is specific and unambiguous. However, it does not name or differentiate from sibling URL tools like domain-shape or browser-url-ok, which could overlap in purpose.

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 provides no guidance on when to use this tool versus alternatives. It does not mention any conditions, exclusions, or scenarios where another tool would be preferred. It is purely a functional statement with no usage context.

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