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 of behavioral disclosure. It states the action (list folders) but does not explicitly note that it is read-only or side-effect-free, nor does it mention any authentication or pagination details. The action implies safety, but absence of explicit disclosure leaves some room for doubt.

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?

A single, grammatically complete sentence states the purpose without redundancy or filler. Every word earns its place, and the key information is front-loaded.

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 simplicity (no parameters, no output schema, no annotations), the description is largely complete for an agent to invoke it correctly. It tells the agent what the tool lists and the account scope. A minor gap is the lack of any mention of the return structure (e.g., folder names vs. full paths), but this is not critical for a low-complexity 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 tool has zero parameters, so schema coverage is effectively 100%. The description needs to add nothing about parameters; the baseline for no parameters is 4, and the description does not detract from it.

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 uses a specific verb 'List' and names the exact resource 'all available IMAP folders/mailboxes' within the scope 'Yahoo Mail account'. It is immediately clear what the tool does and distinct from sibling tools like list_emails or search_emails.

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 gives no explicit guidance on when to use this tool versus alternatives. While it is self-evident that this is for folders and not emails, there is no mention of exclusions or conditions, leaving the agent to infer its place among siblings.

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