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

Annotations declare readOnlyHint=false, and the description justifies that by explaining it actively re-queries DNS 'again now' rather than just reading cached state. It also adds timing expectations (automatic rechecks, DNS propagation lag), which goes beyond the structured hints, though it does not say what a failed or pending result looks like.

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 sentences, purpose front-loaded before the timing caveat, with no filler. The second sentence is slightly conversational but earns its place by setting expectations about automatic rechecks.

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 status-check tool with no output schema and no return-value annotation, the description stops at 'returns its status' and never enumerates possible states (pending, verified, failed) or how the agent should interpret them. Timing context is covered, but the result semantics are 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 description coverage is 100%, so both 'site' and 'domain' are already documented in the schema, and the description adds no syntax or format detail for them. Baseline 3 is appropriate when the schema carries the parameter burden.

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 verb and resource: it looks up a custom domain's public DNS now and returns its status. That is clearly distinguishable from add_custom_domain (write) and list_domains (enumerate all), though the description never names those siblings 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 note that Pagehaus re-checks newly added domains automatically every couple of minutes implicitly tells the agent a manual call is only needed for an immediate re-check, which is useful but not framed as guidance. There is no explicit when-to-use statement and no named alternative (e.g. list_domains) for checking existing state.

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