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

With no annotations present, the description carries the full behavioral burden. It does disclose a key non-obvious trait: no browser is launched. However, it does not say whether a network request is made, whether the operation is read-only, or what side effects might occur.

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 fluff and the most important distinguishing fact is front-loaded. It is concise, though arguably too sparse for a tool with this many parameters.

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?

There is no output schema, no annotations, and thirteen heterogeneous parameters, yet the description only gives the purpose and one behavioral trait. It does not explain what 'opened' means, what the return value is, or how the parameters should be used together.

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?

Every parameter already has a description in the schema, so the baseline is 3. The tool description adds no parameter-level meaning and does not explain how the many unrelated-looking parameters (city, json, path, etc.) relate to checking a URL.

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 states the action: check whether a URL can be opened. The added clause 'No browser is launched' distinguishes it from sibling tools like playwright-url-ok that would actually launch a browser.

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 no-browser clarification implies this is a lightweight alternative to browser-launching checks, but no explicit when-to-use or when-not-to-use guidance is given. It does not name alternatives such as playwright-url-ok, fetch-status, or web-fetch.

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