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

With no annotations, the description carries the behavioral burden; 'No disk access' is a clear and valuable guarantee that the check is purely syntactic and non-destructive. 'Looks safe' also signals heuristic validation rather than filesystem verification. It does not detail the exact return value or error cases, but the yes/no nature is strongly implied.

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, front-loaded sentences with no filler. Both statements—the action and the no-disk-access caveat—earn their 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?

Despite having 9 optional parameters and no output schema or annotations, the description is only one line of functional detail. An agent is not told which parameter(s) to pass, what the response looks like, or what 'safe' means; the no-disk-access note helps but does not make the tool complete to invoke 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?

Schema description coverage is 100%, so the schema already documents every parameter. The description adds no parameter-level meaning beyond naming 'path'; it does not clarify which of the 9 optional parameters should be supplied or whether they are mutually exclusive, so the baseline score of 3 is appropriate.

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 action and resource: 'Check whether a path looks safe' and adds a key constraint, 'No disk access.' This clearly identifies it as a file-path validator and distinguishes it from URL/JSON/title checkers among the siblings. It stops short of a 5 because it does not explicitly differentiate from sibling tools and the input schema exposes many unrelated optional parameters.

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?

There is no guidance about when to use this tool versus alternatives such as normalize-url, validate-json, or browser-url-ok. 'No disk access' hints at a safe validation context, but no explicit when/when-not conditions or alternatives are given.

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