Move email

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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description adds a non-obvious failure condition (virtual source folders are rejected) and the recovery path via find_email_folder, which is real behavioral value beyond the annotations.

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 sentences, no filler. The operation is stated first, then the constraint and the corrective tool, so the critical caveat is front-loaded where an agent will read it.

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 4-required-param mutation tool with full schema coverage and no output schema, the description covers the main pitfall an agent would hit. It does not mention destination-folder existence checks or what happens on partial failure, minor gaps given the schema carries the rest.

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 100%, so the baseline is 3, but the description adds a semantic constraint on sourceMailbox (must be a real folder, not virtual) that the schema only shows as a plain example string. destinationMailbox resolution is still left to the 'list_mailboxes' hint in the schema rather than the description.

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+resource+scope: 'Move an email to a different mailbox folder.' An agent can distinguish this from sibling mutations like mark_email, delete_email, or apply_template without opening any schema.

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 a concrete prerequisite ('sourceMailbox must be a real folder, not a virtual one like "All Mail"') and routes to an alternative tool ('Use find_email_folder first if the email was discovered in a virtual folder'). It does not cover when-not-to-use (e.g., moving vs. deleting/archiving semantics), so it stops short of the full 5.

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