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, but it does not clarify that the tool likely only uses the 'url' parameter and ignores the other eight parameters, nor does it mention error handling or side effects. The minimal disclosure leaves significant behavior undocumented.

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 with no filler. The core behavior is front-loaded, and every word contributes. It is concise and well-structured.

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 9 parameters, no output schema, and no annotations. The description provides only a minimal indication of output ('origin, host, and path') but doesn't explain the return format, how the many parameters interact (or are ignored), or edge-case behavior. For a tool with this complexity, the description is incomplete.

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 all parameters have descriptions in the schema. The description adds no parameter-specific meaning; it doesn't even specify which parameter is the URL to normalize. While the schema's 'url' description covers this, the description fails to connect its purpose to the schema, creating potential confusion. Baseline 3 is appropriate given high schema coverage.

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 the tool returns origin, host, and path from a URL and drops query and fragment. The verb 'Return' and resource 'URL' are specific, and the behavior is unambiguous. However, it doesn't differentiate from sibling tools like browser-url-ok or domain-shape, which also operate on URLs.

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 versus alternatives. There is no mention of when not to use it, no exclusions, and no reference to sibling tools. The description offers no context for selecting this tool over other URL-related tools.

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