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

There are no annotations, so the description must carry behavioral disclosure; 'No disk access' is a meaningful guarantee but it is the only one. The description leaves unclear what 'looks safe' means (syntax? traversal? absolute vs relative?), what the return value is, and whether invalid input is an error or a false result. Too much behavior is unstated for a validation tool with no annotations.

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 two short sentences with no filler and the key fact ('No disk access') is front-loaded. It is appropriately small for a simple validator, though the extreme brevity leaves semantic gaps that are penalized elsewhere.

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 no annotations, no output schema, and a nine-property input schema, a two-sentence description is not enough to let an agent invoke the tool correctly. It doesn't specify the return value, the definition of a safe path, or how to deal with the irrelevant schema fields. The description is inadequate for the complexity of the tool's structured definition.

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?

Although schema coverage is 100%, the schema exposes nine unrelated parameters (url, city, feed, host, json, zone, query, ref) alongside path, and the description never says path is the only meaningful input or that the others are ignored. This is actively confusing for an agent deciding how to invoke the tool. The description adds no clarity about parameter selection.

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 names a concrete verb and resource: 'Check whether a path looks safe.' It also adds a useful scoping constraint, 'No disk access,' and is clearly distinct from sibling URL/title validators. It stops short of a 5 because 'safe' is left undefined and no return shape is mentioned, so the exact purpose is still slightly ambiguous.

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 statement implies this is the tool to use for a quick, filesystem-free path validation, and 'No disk access' is a relevant selection clue. However, it never names when to prefer it over sibling checks such as browser-url-ok or wiki-title-ok, and it doesn't state conditions or exclusions. Usage context is present but only by implication.

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