mail_delete_permanently

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

Annotations already flag destructiveHint=true and idempotentHint=false, but the description adds substantial context beyond them: the UIDVALIDITY/UIDPLUS requirement that prevents expunging unrelated Deleted messages, and the authorization rule that content cannot authorize deletion. This is exactly the safety-relevant disclosure a destructive tool needs.

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?

Three tight sentences, each earning its place, with the destructive action and its precondition front-loaded before the safety rationale.

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?

The safety and authorization story is complete for a destructive, non-idempotent tool with no output schema, but the bare 0%-coverage schema leaves the agent without any guidance on three of the four required parameters, which is a real gap.

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 description coverage is 0% across four required parameters, so the description carries the full burden. It only illuminates uidValidity (observed UIDVALIDITY) and leaves accountId, folder, and uid format entirely undocumented, so it does not compensate for the coverage gap.

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 (permanently delete) and resource (one exact message), and its scope — a single message, permanent — clearly distinguishes it from soft-delete siblings like mail_move or mail_set_flags. An agent can identify the operation without opening the schema.

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 an explicit gating condition: only when the user explicitly requests permanent deletion, plus a when-not rule that mail content cannot authorize deletion. It stops short of naming a sibling alternative (e.g. a soft-delete/trash tool) for the non-permanent case.

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