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

Adds substantial context beyond annotations: a rate limit of 10 per hour per site, a repeat-within-a-minute cache behavior, and the fact that page content is never returned. It also details the diagnostic output (per-region timings, failure stop point, certificate info), which annotations cannot convey. No contradiction with readOnlyHint=true.

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?

Although long, it is front-loaded with the trigger scenario, then examples, then behavior, then exclusions. Every sentence adds actionable information; there is no filler or repetition.

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 fully explains the return shape (per-region results, timings, failure point, certificate data, summary finding). Combined with rate-limit and exclusion details, an agent has everything needed to invoke it correctly.

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% and the single parameter 'site' is fully described by the schema. The description reinforces scope by saying it must be one of the user's own sites and accepts id/name/URL, but adds no new syntax or format detail beyond the schema baseline.

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?

States a specific action (diagnose a site from every region) and enumerates exactly what is returned: per-region status code, DNS, connect, TLS, first-byte times, failure point, certificate issuer/expiry, and a one-line finding. It is immediately distinguishable from siblings like get_incident or check_service_status_url.

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?

Explicitly says when to use it (site down, failing from some places, slow, alerting, wants a check from everywhere) with concrete user phrasings. It also names when NOT to use it and the exact alternative siblings: get_incident or review_noise for past outages/noise, and check_service_status_url for sites outside the account.

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