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

Annotations already indicate destructiveHint=true, readOnlyHint=false, and openWorldHint=true. The description adds substantial context beyond those flags: irreversibility, no response body, shared-account implications, potential to affect other callers' inboxes, and the need for ownership confirmation. This fully discloses behavioral risks and consequences.

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?

Four tight sentences, front-loaded with the core effect, followed by return behavior, risks, and the alternative. Every sentence contributes new, non-redundant information with clear formatting (bold warnings, readable structure). No filler.

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 destructive, irreversible, shared-account mutation with no output schema, the description covers everything an agent needs to invoke safely: what it does, what it returns, why it is dangerous, how to confirm ownership, and what to do instead. Nothing meaningful is missing.

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%, so the input schema already documents both parameters (inbox_id and Authorization). The description adds minor value by tying inbox_id to the recommended get_agentmail_inbox ownership check, but it does not add meaningful parameter-level detail beyond the schema.

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?

Clear, specific verb ('Permanently deletes') and resource ('an inbox and the mail in it'). It clearly distinguishes from sibling delete_* tools that remove smaller items like drafts, messages, threads, or list entries, rather than the inbox itself.

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?

Explicitly tells the agent when not to use the tool ('To stop using an inbox without destroying it, simply leave it alone') and provides a prerequisite: confirm ownership from get_agentmail_inbox before calling. It also warns about the shared-account context, making the usage conditions clear.

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