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

With no annotations provided, the description carries the full burden. It discloses that query and fragment are dropped, which is a key behavioral trait. However, it does not explain how the nine schema parameters (ref, city, feed, json, zone, etc.) relate to the URL operation—whether they are ignored, used as extras, or error triggers. This omission leaves significant ambiguity about the tool's actual behavior beyond the single 'url' parameter.

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 extremely concise: two short sentences with no fluff. The core action is front-loaded, and the dropped components are stated immediately. Every word earns its place.

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 only covers the primary URL behavior but fails to address the purpose of the other eight parameters, leaving agents confused about whether they are valid inputs or ignored. It also does not describe the output format (string? object?) for 'origin, host, path', which is essential for using the result correctly. The description is insufficient for safe and correct invocation.

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% for all parameters, so the baseline is 3. The description adds no extra semantics for any parameter—it only mentions URL implicitly. It does not clarify how the 'url' parameter interacts with the others or what the expected input format is beyond what the schema states (e.g., 'HTTPS URL to normalize or cite').

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's function: 'Return origin, host, and path for a URL. Query and fragment are dropped.' It specifies the exact resource (URL) and the action (return normalized components), which distinguishes it from generic fetch or validation tools. The specificity is high.

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 its siblings (e.g., browser-url-ok, figma-url-shape). It doesn't mention alternatives or exclusions, leaving the agent to infer applicability from the function alone. No context about prerequisites or typical use cases is given.

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