move_message

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

No annotations are provided, so the description must carry the behavioral burden. It discloses the user-approval gate and the same-account constraint (useful, since the schema's destination_mailbox never says cross-account is forbidden), but says nothing about what happens to the message in the source mailbox, whether the destination must already exist, or whether the operation is reversible.

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?

Two short sentences, zero filler, with the core action stated first and the safety gate second. Every clause earns its place.

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 no-annotation mutation with no output schema, the description covers the action, its scope limit, and the approval requirement. It stops short of describing failure modes or the destination-must-exist assumption, which an agent would only learn by trying.

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%, with each parameter (account, mailbox, message_id, user_approved, destination_mailbox) documented in the schema itself. The description adds no syntax, format, or default detail beyond that, so the 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 (move) and resource (a message) with a scope qualifier ('to another mailbox in the same account'). No sibling tool does moving, so an agent can identify it unambiguously from the list.

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 precondition ('Only call after the user explicitly approved this exact action'), which is the key gate for this mutation. It does not mention alternatives or when a move should be preferred over, say, drafting a reply, but there is no real competing tool.

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