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

With no annotations provided, the description must disclose behavioral traits, but it only mentions that no browser is launched. It does not say whether the tool performs a network request, what it returns, how errors are handled, or whether it has side effects. This is insufficient for an agent to predict the tool's behavior confidently.

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 two short sentences with no filler. The main purpose comes first, and the important behavioral caveat 'No browser is launched' is included immediately after. Every word earns its place.

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 optional parameters, no output schema, and no annotations, but the description provides only a two-sentence summary. It does not explain return values, error behavior, network implications, or which parameters are relevant to the URL-open check, leaving significant ambiguity for an agent.

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; the tool description adds no parameter-level meaning beyond the schema. While the parameter descriptions are detailed, the overall tool description does not clarify which parameters actually drive the 'can be opened' 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 clearly identifies the action: check whether a URL can be opened, with the specific qualifier that no browser is launched. This distinguishes it from browser-based tools like playwright-url-ok, though it does not name alternatives explicitly.

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?

The phrase 'No browser is launched' implies this is appropriate when a lightweight, non-browser check is desired, but the description does not explicitly say when to choose this tool over siblings like playwright-url-ok, normalize-url, or web-fetch. Usage context is implicit, not direct.

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