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

With no annotations, the description carries the full behavioral burden. 'No disk access' is a meaningful disclosure that this is a purely syntactic check with no filesystem side effects, but it does not explain what 'safe' means, whether it returns a boolean, or how invalid inputs are handled.

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. The core purpose is front-loaded and 'No disk access' is a valuable non-obvious addition that 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?

Despite its apparent simplicity, this tool has 9 optional parameters, no required fields, no output schema, and no annotations. The description gives no indication of which parameter to use, what the response looks like, or why so many unrelated parameters appear in the schema, making the definition inadequate for reliable 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%, so the baseline is 3. The description itself adds no parameter-level detail, and worse, the schema exposes eight other entirely unrelated optional parameters (url, city, feed, host, json, zone, query) with no hint that only 'path' is relevant for this tool.

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 action ('Check') and resource ('a path'), and the title reinforces the file-path focus, which helps distinguish it from URL- and domain-checking siblings. However, 'looks safe' is vague and does not define what safety criteria are applied.

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 given about when to use this tool versus alternatives like browser-url-ok or domain-shape. The 'No disk access' note is a useful hint but does not state exclusions or selection conditions.

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