list_folders

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

No annotations are provided, so the description carries the full burden. It discloses the return format ('array of {path, name, delimiter} objects') and a behavioral note about using the path in other tools, which is useful. However, it lacks details on permissions, rate limits, or error conditions that would be important for a listing operation.

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 front-loaded with the core purpose in the first sentence, followed by output details and a usage tip. Both sentences earn their place by adding value without redundancy, making it efficiently structured and appropriately sized for the tool's complexity.

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's low complexity (0 parameters, no output schema), the description is mostly complete: it states the purpose, output format, and a key usage guideline. However, without annotations or output schema, it could benefit from more behavioral context like pagination or error handling, but it adequately covers the essentials for a simple listing 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 input schema has 0 parameters with 100% coverage, so no parameter documentation is needed. The description appropriately does not discuss parameters, focusing instead on output and usage, which aligns with the tool's simplicity. A baseline of 4 is given as it compensates well for the lack of parameters by providing clear output semantics.

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 specific verb ('List') and resource ('all folders in the email account'), distinguishing it from sibling tools like list_emails_* which handle emails rather than folders. It precisely defines what the tool does without being vague or tautological.

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 provides clear context for when to use this tool ('List all folders') and implicitly suggests usage for obtaining folder paths needed by other tools. However, it does not explicitly state when not to use it or name alternatives among siblings, such as create_folder for folder creation instead of listing.

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