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

With no annotations to carry the safety profile, the description at least discloses that no browser is launched, which is a meaningful behavioral trait. It does not reveal whether an actual network request is made, what the response looks like, or whether there are side effects, so coverage is incomplete but not misleading.

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?

Two short sentences, with the primary action front-loaded and the critical negative behavior stated immediately after. There is no fluff or redundancy.

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 whose input schema contains seven heterogeneous parameters, no annotations, no output schema, and multiple near siblings, this description is too sparse. It does not clarify whether 'can be opened' means URL-shape validation or an actual network fetch, nor does it explain what the non-url parameters are doing.

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 already provides descriptions for all seven parameters, so the description does not need to repeat parameter meanings; its silence is acceptable. Yet the tool description adds no clarification about how the URL parameter relates to the other parameters such as city, feed, or json, so the agent must rely on the schema.

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 operation ('Check whether a URL can be opened') and adds an important negative scoping fact ('No browser is launched'), which helps distinguish it from browser-launching siblings. It is specific enough about the intended action, though it does not name any alternative 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 purpose statement implies when the tool would be used—when a non-browser openability check is needed—and the 'No browser is launched' sentence hints at a trade-off against a browser-based sibling. However, no explicit when/when-not guidance or named alternatives are provided.

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