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

The description discloses that the tool performs a HEAD request and returns only a status, which is the main behavioral trait. However, it does not explain what happens with the many unrelated parameters or whether ignored inputs affect behavior, so transparency is only partial.

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 main description is concise and front-loaded with the essential action and result. The parameter list is long and noisy, but the descriptive text itself is tightly written.

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 no output schema, no required parameters, and several seemingly irrelevant inputs, the description does not provide enough context to know how to call the tool correctly or what response shape to expect.

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?

Although all 9 parameters have descriptions, most are clearly mismatched with the tool's stated purpose (e.g., 'city', 'json', 'zone'), and even the url description says 'normalize or cite' rather than 'fetch status'. This creates significant confusion about which parameters are meaningful.

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 a specific action ('HEAD a public URL') and output ('return status only'), making the tool's core purpose easy to understand. It stops short of naming sibling alternatives, but the 'status only' qualifier helps distinguish it from content-fetching tools.

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 description implies when the tool should be used (when only an HTTP status is needed via HEAD), but it does not explicitly discuss alternatives or provide decision guidance compared to siblings like web-fetch or browser-url-ok.

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