Batch Modify Gmail Message Labels

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

Annotations already indicate destructive behavior (destructiveHint=true). The description adds no additional safety context beyond the obvious label mutation, such as atomicity guarantees, error handling for missing labels, or rate limits. It provides minimal extra transparency.

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 a single, front-loaded sentence that efficiently conveys the core action. It has no wasted words, though it could be slightly expanded for clarity on batch size limits.

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 presence of an output schema and clear annotations, the description covers the essential functionality. It could mention API prerequisites or batch size limits, but for a straightforward mutation tool, it is sufficiently complete.

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% with clear parameter descriptions for all four parameters. The description does not add any new meaning beyond what the schema provides, so it meets the baseline for high-coverage scenarios.

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 verb 'adds or removes labels' and the resource 'multiple Gmail messages', explicitly noting it is a batch operation. This distinguishes it from siblings like 'modify_gmail_message_labels' (single message) and 'manage_gmail_label' (label creation/management).

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 use for batch operations but does not explicitly state when to use it versus single-message alternatives (e.g., 'modify_gmail_message_labels') or label management tools. No when-not or alternative guidance is provided.

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