email_transfer

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

No annotations are provided, so the description carries the behavioral disclosure burden. It discloses MIME preservation and the copy vs. move duality, but doesn't state required prerequisites (accounts must be configured), whether deleteAfter is non-reversible, or behavioral effects like rate limits. For a mutation-capable tool with zero annotations, this is a meaningful gap but not a dangerous one given the general wording.

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?

Single, efficient sentence with no wasted words. It front-loads the core action (move/copy between accounts) and adds the distinguishing detail (preserving raw MIME). However, some behavioral detail could be traded for the concise form without losing much.

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?

This is a complex tool with 7 parameters (5 optional) that can mutate data across accounts, has no output schema, no annotations, and minimal schema coverage (14%). The description adds nothing about the copy-vs-move mechanism (how deleteAfter interacts with move semantics), what happens to existing labels/folders, or error conditions. For a tool of this complexity and destructive potential, the description is under-specified.

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 very low at 14%, with only sourceFolder having a description. The tool description doesn't explain what sourceAccountId, targetAccountId, emailIds, markRead, or deleteAfter mean beyond their names. However, most parameter names are self-explanatory (sourceAccountId, targetAccountId, emailIds, markRead, deleteAfter). The deleteAfter and markRead semantics would benefit from explanation but their names carry reasonable meaning.

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 states a clear verb+resource: 'Move or copy emails between accounts while preserving raw MIME'. It clearly distinguishes from siblings like email_move (which moves within an account) and email_batch_move by specifying 'between accounts'. The MIME preservation detail adds specificity.

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 description implies cross-account transfers but doesn't explicitly state when to use this versus email_move/email_batch_move, or when not to use it. It gives no context about account setup requirements (e.g., target account must exist first). Usage guidance is implied by the tool name and sibling grouping rather than being explicit.

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