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 'No browser is launched,' but omits what the tool actually does with the parameters, whether it makes network calls, what it returns, or what side effects occur. The schema hints at discarding and length checks, but the description fails to explain these behaviors.

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 with no structural breakdown. While it is short, this is under-specification rather than effective conciseness—every sentence should earn its place, but this one lacks the necessary detail to be useful.

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 9 parameters, no output schema, no annotations, and a one-line description, the tool is severely under-documented. The agent cannot determine what results to expect, how inputs are validated, or what 'can be opened' actually checks. This is far from complete for a tool with such a broad parameter set.

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 coverage is 100% with each parameter individually described, so the schema already provides clear meanings for each input. However, the description adds no information about how these parameters relate to the tool's core purpose, leaving the overall parameter semantics disconnected from the stated function. Baseline 3 is appropriate because schema does the heavy lifting, but the description offers no added value.

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 'Check whether a URL can be opened' which gives a verb and resource, but it's vague about what 'can be opened' means and how the many unrelated parameters (city, json, path, etc.) fit into that purpose. It does not differentiate from sibling tools like browser-url-ok or normalize-url, making it unclear what specific check this performs.

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 conditions, prerequisites, or exclusions. An agent has no context to decide between playwright-url-ok and other URL-related tools.

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