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

No annotations are provided, so the description must fully disclose behavior. It only states 'No browser is launched,' but does not reveal what the tool actually does (e.g., network request, validation, side effects). The parameter descriptions mention 'discarded' and 'no disk access,' but these are inconsistent with the stated URL-checking purpose, making behavior opaque.

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 a single sentence and concise, but it is under-specified. It lacks structure and essential details, and it does not front-load information about the tool's scope or behavior. The brevity comes at the cost of usefulness.

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?

With nine parameters, no output schema, and no annotations, the description is severely incomplete. An agent cannot determine what inputs are needed, what the return value looks like, or how to interpret results. The description does not cover the full scope of the tool's capabilities, making it inadequate for correct invocation.

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 provides 100% coverage with terse descriptions, but the tool description does not reconcile these with its stated purpose. For example, the 'url' parameter is described as 'HTTPS URL to normalize or cite' in the schema, while the tool says 'check if can be opened' – a mismatch. The description adds no clarity on how the nine parameters are used or which are relevant for the stated check.

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 and resource ('Check whether a URL can be opened') but does not clarify what 'opened' means (HTTP status, format, etc.) and the schema lists nine unrelated parameters (city, feed, json, zone) that contradict the narrow purpose. The name implies Playwright but says no browser is launched, creating ambiguity about the actual check.

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 provided about when to use this tool versus siblings like 'browser-url-ok' or 'fetch-status'. There is no mention of alternatives, conditions, or exclusions, leaving an agent unable to choose between them.

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