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

Beyond the annotations, the description discloses important behavior: emails remain in Trash, can be restored or permanently deleted later, no tool permanently deletes email, and moved emails receive new UIDs with old UIDs listed as stale. This adds substantial operational context not captured by destructiveHint or idempotentHint alone.

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?

The description is front-loaded with the core action, then adds only relevant behavioral context. Every sentence contributes to correct tool selection or invocation.

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?

Given the annotations, full schema coverage, and presence of an output schema, the description supplies the remaining critical context: reversibility, non-permanent deletion, Trash-folder identification, and UID staleness after the move.

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 100%, so the schema already defines email, mailbox, and uids. The description adds related behavioral detail about UID changes, but it does not further clarify parameter formats or constraints beyond what the schema provides.

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 names a specific verb and resource: moving emails to the account's Trash folder. It clearly distinguishes this from general moving by explaining Trash-folder resolution and by framing it as the removal mechanism for these tools.

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?

It clearly explains that this is how the tools remove email and that removal is reversible, giving strong context for when to use it. It does not explicitly name move_email or state when to choose a general move instead, so it falls short of full alternative routing.

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