List Inbound Mailboxes

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, covering safety. The description adds useful behavioral context about the mailbox purpose and specifies the returned JSON array and its fields, which goes beyond the annotation-only view.

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 short, front-loaded with the core listing purpose, and every sentence adds value: purpose, usage context, and return shape. No filler or redundant restatement of the tool name.

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 parameterless read-only listing tool, the description is complete: it states the resource, the intended workflow, and the return structure including field names. There is no output schema, so the description appropriately carries the return-format burden.

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 has zero parameters, so there are no parameter semantics to document. The description appropriately avoids inventing parameters, and the baseline of 4 applies because the schema fully covers an empty parameter set.

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 resource ('inbound email addresses') and a clear use case ('forwarding purchase confirmation emails'), so an agent knows exactly what this tool returns. It is readily distinguishable from sibling list tools such as list_documents and list_categories.

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 explains when the tool is useful: users forward store emails to these addresses for automatic receipt processing. It does not explicitly name alternatives or exclusion cases, but the context is clear enough for selection among the siblings.

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