List Mailbox Folders

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

Annotations already indicate readOnlyHint=true and destructiveHint=false. The description adds value by stating what the response includes (unread counts, folder IDs, relevance to rules/automations), giving the agent behavioral context beyond the safety profile.

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?

Single, front-loaded sentence that packs essential information (verb, resource, output highlights) without extra words. Every part earns its place.

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 simple list tool with one parameter and an output schema, the description covers the key aspects: what is listed, what data is returned, and a hint of practical use (inbox rules, automations). No missing context for correct agent usage.

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 coverage is 100% for the single parameter 'id', which has a meaningful description. The description does not elaborate on the parameter further, but the schema itself is sufficient. No added semantics beyond schema.

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?

Description clearly states verb ('List'), resource ('system and custom folders for a mailbox'), and includes specific output details (unread counts, folder IDs). It distinguishes from sibling tools like shipmail_create_mailbox_folder or shipmail_delete_mailbox_folder by being a read-only list operation.

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 explicit when-to-use or when-not-to-use guidance is provided. The description implies this tool is for retrieving folder information, but does not name alternatives or exclude scenarios, relying on sibling context to differentiate.

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