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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered; the description adds real value on top by stating the account-token requirement, that the check is performed live at call time, and that the backend variant issues exactly one request.

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?

A single dense sentence with the prerequisite front-loaded in parentheses and the read-only property at the end; no wasted clauses, though the parenthetical and mid-sentence 'backend true' phrasing is slightly awkward to parse.

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, the description should clarify what the live check returns (a boolean, a status object, per-check results?) and it does not. The auth requirement and backend mode are covered, but the response shape an agent needs to interpret results is left implicit.

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 both parameters are already documented, and the description largely restates the backend flag ('sends one request to the linked backend instead') without adding format or syntax detail. Baseline 3 applies when the schema does the heavy lifting.

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?

Specific verb+resource with the exact checks enumerated: address points here, valid certificate, loads. That is far more informative than the name alone. It does not, however, contrast itself with the sibling site_status, leaving the agent to infer which diagnostic to pick.

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 '(needs account token)' prerequisite and the 'backend true sends one request to the linked backend instead' branch give usable context, but there is no explicit when-to-use or when-not-to-use guidance relative to site_status or the other site inspection tools.

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