move-message

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

No annotations exist, so the description carries the burden. It clearly discloses that the tool 'moves a real message between folders' and includes a safety warning. It also states the return value (a confirmation naming the destination mailbox). While it doesn't detail potential failure modes or permission requirements, it provides adequate transparency for a simple mutation.

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?

Every sentence earns its place. The description uses a clear 'Use when'/'Do not use when' structure, includes a return note, and ends with a safety caveat. It is concise (about 3 sentences) and front-loaded with the most critical information.

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 simplicity of the tool (3 params, no nested objects) and the presence of an output schema, the description covers the essential aspects: when to use, alternatives, safety, and return value. It could mention error conditions or edge cases (e.g., what happens if the mailbox doesn't exist), but it preemptively advises to confirm the mailbox. This is complete enough for typical use, though not exhaustive.

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 only 33% (only 'account' has a description). The tool description clarifies that 'id' refers to the message id and 'mailbox' to the destination folder, adding meaning beyond the schema. However, 'account' is left to the schema's description, and no additional context is given for the id pattern or mailbox naming conventions. The description partially compensates for the low coverage but does not fully explain all parameters.

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 clearly states the action: 'moving a single message (by id) into another mailbox/folder' with examples (archiving, filing). It distinguishes itself from batch-move-messages and delete-message, making the tool's unique scope explicit.

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?

Extremely explicit usage guidance: includes 'Use when' and 'Do not use when' with specific alternatives (batch-move-messages, delete-message). Also advises using list-mailboxes to verify destination and search-messages/list-messages to confirm id, providing a clear decision framework.

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