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

With annotations only flagging readOnly=false, openWorld=true, idempotent=false, destructive=false, the description adds genuinely non-derivable behavior: fresh public data is reused, failed or partial queries preserve the last complete observation and its date, and there is a hard budget of 100 cold page reads per owner per UTC day. These caching, failure, and rate-limit semantics go well beyond the annotations. Auth/permission requirements and expected latency are still unstated.

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 operation's scope is front-loaded well and the rate limit appropriately closes the description. But "Reuses fresh public data. Reuse fresh observations." is near-duplicative filler, and the telegraphic fragment style makes the subject of the first sentence ambiguous (what exactly is being refreshed?).

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 mutating, open-world refresh with no output schema and only two of four annotation hints carrying detail, the description covers reuse, failure preservation, and throttling, which is decent. It still omits what the result conveys, why a tab `id` is required, and how this relates to `domain_status`, leaving meaningful gaps for an agent choosing between them.

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 only 50%: `id` is documented in the schema as an owned tab ID from list_tabs, while `guest_token` is undocumented there and gets no explanation in the description. The description mentions "per owner" but never connects that to any parameter, so it fails to compensate for the coverage gap.

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 states a specific verb ("Refresh") and enumerates the resource facets it re-collects: registration, contacts, TLS, DNS, mail policies, certificate issuance, and a DNS/TLS sample. An agent can form a concrete picture of the operation. However, it never distinguishes itself from the sibling `domain_status` (or `get_audit`), so the reader must guess how 'check' differs from 'status'.

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?

There is no explicit when-to-use or when-not-to-use statement, and no sibling is named as an alternative. The clues about reuse ("Reuses fresh public data") imply it is safe to re-invoke, but the agent gets no routing guidance versus `domain_status`, `audit_url`, or `list_tabs`.

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