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

Adds substantial behavior beyond annotations: the call returns a queued operation rather than a confirmed result, the polling target is named (get_mail_action), and retry safety with the idempotency key is spelled out. This async/eventual-consistency model is exactly the kind of trait annotations (destructiveHint, idempotentHint) cannot express.

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, safety-critical asynchronous behavior front-loaded. Minor waste/confusion from 'never retry an uncertain send', wording inherited from a send operation rather than an archive one.

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?

No output schema exists, yet the description explains what is returned (a queued operation with an operationId) and how to resolve it. Missing only folder/permission preconditions, which keeps it short of a 5.

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 67% and the schema itself already documents messageId thoroughly and operationId as an idempotency key. The description only reinforces the operationId retry rule, adding little beyond the schema; accountId remains undocumented in both places. 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 and resource ('Archive a message from its current folder'), which is clear on its own. It does not, however, explicitly distinguish itself from the sibling move_email, which is the closest alternative for relocating a message.

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?

The description gives post-invocation guidance (poll get_mail_action with the operationId, don't retry with a new operationId) but never states when to archive versus move_email or delete, nor any precondition such as required folder state. Usage context is implied rather than explicit.

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