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

With no annotations, the description must carry the full burden. It discloses the core behavior (returning origin/host/path, dropping query/fragment) but fails to mention that the tool discards all parameters except 'url' and does not describe error handling or edge cases, leaving significant behavioral gaps.

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 concise sentence that front-loads the core action. However, it is too brief to resolve the schema confusion, and a bit more structure could clarify the parameter situation without sacrificing conciseness.

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 with 9 optional parameters, no output schema, and no annotations, the description is drastically incomplete. It omits which parameter to use, the fact that all others are ignored, and the exact output format, leaving the agent with insufficient information to invoke the 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?

The description does not clarify which parameter is the URL to normalize, even though the schema has 9 parameters with 100% description coverage. The schema itself is misleading (e.g., 'ref', 'city' are described as discarded), and the description adds no mapping between its stated purpose and the actual parameters, so the agent cannot correctly identify the input to use.

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 clear purpose: return origin, host, and path for a URL, and explicitly drops query and fragment. It is specific and actionable, though it does not differentiate from sibling tools like domain-shape or url-path-len.

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 given on when to use this tool versus alternatives. With many sibling URL-related tools, the agent gets no direction on selection criteria or when not to use it.

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