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

With no annotations present, the description carries the transparency burden. It proactively states that no browser is launched, which is a meaningful behavioral disclosure. However, it does not clarify whether any network request is made, what side effects may occur, or what the result represents.

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 short and front-loaded, with two sentences containing no filler. It is efficiently worded, though given the large schema and sibling set, a bit more guiding context would be beneficial.

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?

For a tool with 9 optional parameters, no output schema, and no annotations, the description is too sparse. It does not explain how the parameters should be combined, what 'can be opened' means operationally, or what the tool returns. The sibling list suggests a shape-check family, but the description does not connect to that context.

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 each parameter. The description adds no parameter-level meaning beyond the schema, making the baseline score of 3 appropriate. It does not explain how the many optional parameters relate to the stated URL-checking purpose.

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 verb and resource: 'check whether a URL can be opened.' It also adds a key differentiator from browser-launching siblings via 'No browser is launched.' However, the large set of unrelated input parameters makes the exact scope 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 description implies a use case—checking URL openability without launching a browser—but it gives no explicit guidance on when to choose this over siblings like playwright-url-ok, fetch-status, or normalize-url. No exclusions or alternative-selection criteria are provided.

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