list_mailboxes

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

With no annotations provided, the description must fully disclose behavioral traits. It only says 'List mailboxes,' with no mention of authentication requirements, read-only nature, pagination, or any side effects. This leaves the agent without crucial context.

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 description is a single, focused sentence with zero unnecessary words. It is front-loaded and efficient, perfectly concise for what it says.

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?

Despite being a simple tool with an output schema, the description is too sparse to be considered complete. It does not distinguish from related tools like list_mailbox_members, describe the scope of mailboxes returned, or mention any special behavior. Given the existing context, a richer description would be expected.

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?

The schema has one optional parameter, api_token, with 0% schema description coverage. The description does not mention this parameter at all, leaving the agent to guess its purpose from the name alone. The description adds no value beyond the schema in this regard.

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 clearly states the action ('List') and the resource ('mailboxes'), which is a distinct resource from the siblings (e.g., list_conversations, list_labels). However, it lacks any elaboration on scope or what constitutes a mailbox, so it is not as informative as 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?

No guidance is provided on when to use this tool versus alternatives like list_mailbox_members or list_conversations. There is no mention of use cases, prerequisites, or conditions under which this tool should be preferred.

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