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

Annotations already flag destructiveHint=true, so the safety profile is known, yet the description adds a non-obvious consequence: contained messages are deleted too, with no automatic unfiling. That is exactly the kind of behavioral detail annotations cannot express, plus an explicit human-confirmation requirement.

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?

Front-loads the action, then the warning, then the prerequisite and confirmation ask in a single tight sentence. No filler; every clause carries actionable information.

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?

With no output schema and only two params, the description covers the destructive semantics and confirmation duty well. The one gap is sourcing folderId, which is undocumented in both the schema and the description.

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 only 50%: 'mailbox' is well documented (including a pointer to list_authorized_mailboxes), but 'folderId' has no schema description at all and the description does not explain where to obtain it (e.g. list_mail_folders). The description adds no parameter meaning of its own.

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+resource ('Delete a mail folder'), which cleanly separates it from sibling deletes of other resource types. It does not explicitly distinguish itself from adjacent folder tools such as merge_mail_folders or rename_mail_folder, though the verb makes the distinction obvious.

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?

Gives clear preconditions: relocate anything worth keeping first and get user confirmation before calling. It implies move_messages as the alternative action but never names it, so the routing guidance is contextual rather than explicit.

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