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

Annotations already declare read-only, idempotent, non-destructive, and closed-world behavior. The description adds genuine value beyond this by ruling out a side effect ('Does NOT verify domains') and clarifying account scoping, which is not derivable from structured fields.

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?

Three short sentences, front-loaded with the core action and free of filler. Tight and readable, though the two 'Does NOT' clauses read slightly as defensive padding.

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 simple read-only lister with annotations covering the safety profile and no output schema, the description is adequate on scope and side effects. However, it omits the one parameter's meaning and any indication of the returned shape or pagination.

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?

With one parameter (include_archived) and 0% schema description coverage, the description carries the burden of explaining it but never mentions it. The default behavior for archived sites is left entirely unstated.

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 ('List sites on this account') and scopes it to the account, distinguishing it from per-site tools like crawl_site and check_vitals. It doesn't explicitly name a sibling alternative, so it falls short of a 5.

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 negative clarifications ('Does NOT include other users', 'Does NOT verify domains as a side effect') imply usage context, but the description never states when to reach for this tool versus related ones. Usage is only implied.

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