list_mailboxes

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

The description accurately reflects the tool's behavior as a read-only listing operation. With no annotations provided, the description correctly indicates no side effects or special requirements. It could add more detail (e.g., 'this operation is non-destructive'), but the simplicity of the tool limits the need.

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 (17 words) that is front-loaded with the verb and resource, followed by examples. Every word earns its place, and there is no redundant information.

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?

Given the tool has no parameters, no output schema, and a straightforward purpose, the description fully covers what an agent needs to know: what it lists and representative examples. No additional information is necessary.

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?

No parameters exist in the schema, so the description does not need to explain parameters. The description adds no parameter semantics, but the baseline for zero parameters is 4.

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 'all IMAP folders/mailboxes in the mailbox', with concrete examples (INBOX, Sent, Drafts, Trash). It distinguishes from sibling tools which deal with messages rather than folders.

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 clearly indicates when to use this tool (to list IMAP folders), and the context implicitly excludes alternatives since no sibling tool lists folders. It could be improved by explicitly stating 'use this to see the folder structure before working with messages', but the current text is sufficient.

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