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

The description discloses one important behavioral trait: 'No disk access' — indicating the check is static and non-destructive. However, it does not explain what 'safe' means, what the return value is, or how errors are reported, leaving some aspects implicit.

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 that deliver the essential message without any redundancy. It is well-structured and easily parsed.

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's complexity (9 parameters, no required fields, and no output schema), the description is far too brief. It does not explain what 'safe' means, what the return value is, or how to interpret the various parameters, leaving an agent without sufficient context to use the tool 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?

The description only references 'path', but the input schema lists eight other parameters (ref, url, city, feed, host, json, zone, query) without any explanation of their role. The description fails to clarify which parameters are actually used and how they relate to the tool's purpose, making it largely unhelpful for understanding the parameter semantics.

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 clearly states the tool's purpose: checking whether a path looks safe, with an explicit note that no disk access occurs. This makes the core function unambiguous, though it does not explicitly differentiate from sibling tools that might also deal with path-like inputs.

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 such as browser-url-ok or normalize-url. There is no mention of conditions, use cases, or criteria for selecting this tool.

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