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

No annotations are supplied, so the description carries the full burden of behavioral disclosure. It states that no WHOIS/ownership data is retrieved, which implies a non-network operation, but it says nothing about output format, error behavior, or side effects. It also fails to explain the purpose of the many unrelated parameters, leaving significant ambiguity about the tool's behavior when other fields are supplied.

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, efficient sentence that front-loads the core action. It avoids filler and is easily skimmable. However, the brevity may contribute to the incompleteness noted in other dimensions, as it omits essential context about the parameter surface.

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?

With nine optional parameters, no output schema, and no annotations, the description is inadequate. It explains only one use case (hostname splitting) and leaves the other eight parameters unexplained in terms of how they should be used together or what the tool does with them. An agent cannot confidently determine correct invocation for anything beyond the simplest hostname input.

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 each parameter already has a description. The tool description adds no additional parameter-level meaning—it only implies that the 'host' parameter is the target for splitting, but it never states which parameter to use. The schema descriptions themselves are informative (e.g., 'discarded after the shape check'), but the description does not enrich or disambiguate them.

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 ('Split') and resource ('a hostname') and clarifies what it does not do ('without WHOIS or ownership data'). This is clear for the hostname use case. However, the schema exposes nine optional parameters, most unrelated to hostnames, and the description does not acknowledge this broader surface, so an agent could be misled about what the tool actually accepts.

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 conditions, exclusions, or comparison to sibling tools like github-repo-shape or normalize-url. The description simply states what it does without situating it among the other shape/format tools.

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