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 behavioral burden. It discloses the returned counts, which is useful, but says nothing about whether folders are hierarchical/flat, whether counts cost a server round-trip, permission requirements, or pagination.

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 tight sentence with the resource and payload front-loaded and zero filler. It is efficient, though its brevity is partly the source of the missing guidance.

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, zero-required-parameter read tool with no output schema, the description adequately covers purpose and return contents. Only minor gaps remain, such as folder hierarchy and count semantics.

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?

There is exactly one parameter and schema description coverage is 100%, so the schema already explains 'account'. Per the baseline rule for high coverage, 3 is appropriate; the description adds no extra meaning about the account parameter.

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?

States a specific verb (List) and resource (mailbox folders) plus the returned data (message and unseen counts), which clearly separates it from siblings like list_accounts and search_messages. It does not explicitly name alternatives, but the resource is unambiguous.

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?

There is no when-to-use guidance, no prerequisites, and no mention of alternatives. A reader can infer it is a discovery operation (useful before move_messages or search_messages), but the description never states that.

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