list_folders

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

With no annotations, the description carries the full burden. It discloses meaningful behaviors: special-folder detection, case sensitivity of folder names, and possible nesting. The read-only nature is clear from 'List', and no side effects are implied. It stops short of describing response format or account-selection behavior, but core transparency is solid.

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?

Two purposeful sentences with no filler. The primary action is front-loaded, and the critical guidance about case sensitivity and taking names from here is delivered as a concise, actionable directive.

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?

The core purpose and a key constraint are present, making the tool usable in simple cases. However, the description does not explain how the optional account parameter behaves, what a response contains, or how this interacts with account selection, especially given the sibling list_accounts tool.

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 only parameter, 'account', is optional with a default but is never mentioned in the description. Since schema description coverage is 0%, the description should compensate by explaining which mailbox account the tool acts on or what an empty account means, but it does not.

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 states a specific action ('List') and a specific resource ('every folder in a mailbox'), and adds the useful detail that Sent, Trash, and Drafts folders are detected. This clearly distinguishes it from siblings like list_accounts, search_messages, or get_message.

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 phrase 'always take names from here rather than guessing' gives the agent a clear directive to use this tool as the authoritative source for folder names. It implies the tool should be used before operations that require exact folder names, though it does not explicitly name alternatives or exclusions.

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