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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does state 'No disk access,' which is useful, but it fails to disclose that the tool accepts and discards a variety of input types (as implied by the schema's 'discarded after the shape check' notes). It also does not describe the return format, error behavior, or side effects. The mismatch between the path-focused description and the multi-input schema is a transparency gap.

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, consisting of two short sentences. The core purpose is stated first, and the safety note ('No disk access') is front-loaded. There is no wasted text, and it is appropriately brief for a simple shape-checking tool, even though it underrepresents the schema's breadth.

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?

Given the tool has 9 optional parameters and no output schema, the description is critically incomplete. It does not explain what the tool actually does with the non-path parameters, nor does it describe what the agent should expect as a return value. The mismatch between the description and the schema leaves an agent uncertain about how to invoke the tool correctly, making it inadequate for a tool of this complexity.

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 input schema provides descriptions for all 9 parameters, achieving 100% coverage. The tool description adds no additional parameter semantics; it does not explain how the parameters relate to the 'path' check or why fields like 'url' and 'json' are included. Since schema coverage is high, the baseline of 3 applies, but the description adds zero value beyond the schema.

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 verb ('check') and resource ('path'), but it is misleading because the schema accepts 9 different input types (ref, url, city, feed, host, json, path, zone, query). It does not accurately convey the tool's actual scope as a generic shape checker, and it does not differentiate from sibling shape-checking tools beyond mentioning 'path' and 'no disk access'.

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 that it should be used for path validation, nor does it direct agents to other tools for URL, domain, or other shape checks. The only implicit hint is the word 'path', but with many sibling tools, this is insufficient.

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