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

The only behavioral disclosure is 'No browser is launched,' which is a useful trait but far from sufficient. The description omits what the tool actually does with non-URL parameters, whether it performs network requests, what it returns, or any side effects. With no annotations, the description carries the full burden and fails to meet it.

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 short, but this is under-specification rather than efficient conciseness. It front-loads the URL check but entirely omits the other eight parameters and any operational details, making it insufficient for correct invocation.

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 optional parameters, no output schema, and no annotations, the description is severely incomplete. It does not explain what the tool returns, how it handles each input, or why the extra parameters exist. An agent cannot infer correct usage from this description alone.

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 schema has 100% parameter coverage, but the descriptions are generic and do not explain how each parameter relates to the tool's purpose. The tool description adds no clarity; for instance, 'city' and 'zone' appear unrelated to URL checking. The description fails to compensate for the lack of semantic cohesion among the nine parameters.

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 specific verb and resource ('check whether a URL can be opened'), but it is misleading because the schema includes nine parameters, most of which are not URLs (e.g., city, json, path). It does not clarify what 'can be opened' means or distinguish this tool from siblings like browser-url-ok or fetch-status.

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 on when to use this tool versus alternatives. It does not mention any prerequisites, exclusions, or typical scenarios, leaving the agent without direction on selecting it over similar sibling tools.

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