List Mailboxes

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

The description discloses that this is a read-only operation ('List') scoped to a mail order. However, it does not describe response format, pagination, or error behavior. Since no annotations are provided, the description carries the burden, but for a simple list tool, the basic behavior is clear.

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 sentence, front-loaded with the action and resource, with no redundant words. It is appropriately concise for a tool with one parameter.

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?

With one parameter, no output schema, and no annotations, the description is minimal but sufficient for the agent to understand the tool's core function. It lacks details about the return structure and edge cases, but given the simplicity, it meets minimum viability.

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 input schema already provides 100% coverage with order_id described as 'Mail order ID'. The description reinforces this by saying 'for a mail order' but adds no additional format, validation, or example details. Baseline of 3 is appropriate given high schema coverage.

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 'List mailboxes for a mail order' uses a specific verb ('List') and resource ('mailboxes') with a scope ('for a mail order'). It clearly distinguishes from sibling tools like mail_orders_list, which lists orders, and mail_aliases_list, which lists aliases.

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 description implies usage: when you need mailboxes for a specific mail order, this is the tool. It does not explicitly mention when not to use it or provide alternatives, but the scope 'for a mail order' gives enough context for a simple list operation.

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