List mail folders

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds only the protocol note ('IMAP') and nothing behavioral: no indication of whether folders are returned flat or hierarchical, whether special-use folders are included, or any auth/connection requirements – and there is no output schema to fill that gap.

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?

One short sentence with no waste and the verb/resource front-loaded. It is arguably too terse for a tool with no output schema, but there is nothing superfluous to cut.

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 read-only list tool with one optional parameter and annotations covering safety, the definition is minimally complete. However, with no output schema, the description should say something about what is returned (folder names, hierarchy, separators), which it omits.

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% and the single optional 'server' parameter is fully documented in the schema (including the default behavior), so the description cannot add much. It says 'for an account,' loosely echoing the parameter without new syntax or format detail – the baseline 3 applies.

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 ('IMAP mailboxes/folders') scoped to an account, so the agent can distinguish it from email_list (messages) and list_servers (servers). It doesn't explicitly name any sibling, but the resource is specific enough to route correctly.

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 such as email_list, list_servers, or email_create_folder. The agent must infer that this is for enumerating folder names before a move/create/delete operation.

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