List email accounts

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds a modest amount of value by naming the returned attributes (disk usage, quota, suspension status), but says nothing about pagination limits, result ordering, or behavior when the user has no mailboxes.

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 well-formed sentence with the resource front-loaded and zero filler. It is efficient, though it is thin enough that it could carry one more clause about scoping or pagination without becoming bloated.

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 read-only list tool with four fully documented parameters and complete annotations, the definition covers what it returns and what it operates on. With no output schema present, a brief note on pagination or empty-result behavior would have made it fully self-sufficient.

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% and every parameter carries a meaningful description, including a cross-reference from `user` to whm_list_domains. The tool description adds no parameter-level detail beyond that, but with full schema coverage the baseline of 3 is raised slightly by the description scoping results to a single account's mailboxes.

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 names a specific verb and resource ("List an account's mailboxes") and even enumerates the fields returned, so it is clearly distinct from siblings like whm_list_email_forwarders or whm_list_domains. It stops short of explicitly contrasting itself with those siblings, which keeps it from 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?

Usage is only implied: the agent can infer this is the tool for enumerating mailboxes belonging to a given cPanel user. There is no explicit when-to-use/when-not-to-use guidance and no mention of the adjacent forwarder or delivery-search tools as alternatives.

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