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

With no annotations, the description carries the full burden of behavioral disclosure. It only states that no browser is launched, but does not clarify whether network requests are made, what checks are performed, or what side effects occur. The phrase 'can be opened' is vague, and the behavior regarding the unrelated parameters is entirely unexplained.

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 only two sentences and not verbose, so it earns points for brevity. However, it is so terse that it omits critical context, and the structure does not lead the reader through logical steps. It is acceptable but not exemplary – the minimal length compromises the clarity it should provide.

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?

This tool has 9 parameters, no output schema, and no annotations. The description supplies only a minimal purpose statement and one behavioral snippet. It fails to explain how the tool processes its many inputs, what the return value represents, or when to invoke it. For an agent to correctly select and call this tool, the description is severely incomplete.

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 with no parameter information in the description. The schema individually documents each parameter, but the description adds no context on how these parameters relate to the tool's purpose. Since the schema is comprehensive, the baseline is appropriate; however, the lack of relational context limits the score to 3.

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 verb ('check') and a resource ('URL') but the meaning of 'can be opened' is ambiguous – does it imply network reachability, syntactic correctness, or something else? It fails to differentiate from siblings like normalize-url, fetch-status, or playwright-url-ok. The schema's nine unrelated parameters (ref, city, json, path, etc.) further muddy the core purpose, making it unclear what the tool actually does.

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?

There is zero guidance on when to use this tool versus the many sibling tools (e.g., playwright-url-ok, fetch-status, normalize-url). No preferred use cases, exclusions, or conditions are mentioned. An agent has no basis to choose this tool over alternatives.

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