Update forwarder keep-copy setting

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

Annotations already signal a non-read-only, idempotent, destructive write, and the description does not contradict them. It adds little beyond that: it does not clarify whether disabling keep-copy deletes existing copies, whether the forwarder must be verified, or what side effects the destructive flag implies.

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?

A single, direct sentence with no filler. The action is front-loaded and the rest of the needed detail is delegated to the schema and annotations.

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 two-parameter operation with no output schema and no nested objects, the description plus the fully documented schema and annotations are sufficient for an agent to invoke it correctly. The only gap is side-effect details around disabling keep-copy, but that is not essential for making the call.

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?

The schema already documents both parameters with 100% coverage: forwarderId is 'Forwarder resource ID' and is_keep_copy_enabled is 'Whether to keep a copy of forwarded messages in the mailbox'. The description restates the boolean's purpose but does not add format, default, or behavioral details.

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?

The description uses a specific action ('Enable or disable') and names the precise resource ('keeping a copy of forwarded messages in the mailbox'), so an agent can tell this toggles a forwarder's retention setting. It is clear but does not explicitly differentiate from sibling forwarder operations such as mail_createForwarderV1 or mail_deleteForwarderV1, so it stops short of a 5.

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 intended use is implied: call this when you need to change whether a forwarder keeps copies of forwarded messages. However, there is no explicit statement of when not to use it, no mention that the forwarder must already exist, and no reference to alternative forwarder-related tools.

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