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

With no annotations, the description carries the burden of disclosing behavior. It does explicitly state 'No disk access', which is a meaningful and useful behavioral constraint. However, it does not disclose the return type, failure behavior, or what 'safe' means in terms of rejected patterns, so transparency is only partially satisfied.

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 very short and front-loaded: the main purpose appears immediately, followed by the crucial 'No disk access' caveat. No words are wasted, though the extreme brevity leaves important context unstated, so it earns 4 rather than 5.

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 nine parameters, no output schema, and no annotations, the description is incomplete. It does not explain the purpose of the non-path fields, state what the tool returns, clarify how 'safe' is determined, or indicate whether parameters are alternatives or combined. An agent would struggle to invoke this tool correctly beyond guessing the path parameter.

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 even though the description adds little about parameters. The description focuses on 'path' but the schema exposes seven unrelated fields, creating a mismatch that the description does not address.

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 uses a specific verb ('Check') and resource ('a path'), and adds 'No disk access' to clarify that this is a static/shape-only check, distinguishing it somewhat from sibling URL-checking tools. However, 'looks safe' is somewhat vague about what safety criteria are applied, so it is not a perfect 5.

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 browser-url-ok, playwright-url-ok, normalize-url, or other sibling validators. The description also does not explain whether this tool should be preferred for file paths or whether it can validate the many other input fields in the schema.

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