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

With no annotations provided, the description carries the full burden. It discloses that no browser is launched, which is a useful behavioral trait. However, it does not state whether the check involves a network request, what the success/failure criteria are, or any side effects. The single disclosure is minimal but non-contradictory.

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 exceptionally concise: two sentences, both useful. It front-loads the main purpose and adds a key behavioral note. It does not waste words, but it is arguably under-specified given the tool's complexity.

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 far too thin. It does not explain what 'can be opened' means, what the return value is, which parameters are required for a typical call, or how to interpret the many 'discarded' parameters. An agent would be unable to reliably invoke this tool correctly based solely on this description.

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%, so each parameter is described individually. However, the tool description does not clarify how these parameters relate to the URL check. Many parameters (ref, city, zone, query) are described as 'discarded' or unrelated, but the description does not explain which parameter is the primary one or how to use them together. The description adds no value beyond the schema and even creates confusion about the tool's actual input.

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 adds the constraint 'No browser is launched,' which gives some specificity. However, it does not distinguish from sibling tools like playwright-url-ok or normalize-url, and the schema includes many unrelated parameters (city, json, path, zone, query) that obscure the core purpose.

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 that playwright-url-ok might be preferred for full browser-based checks, or that normalize-url is for normalization. An agent has no context to choose among siblings.

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