gmail_message_modify

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

Annotations are absent, so the description must fully disclose behavioral traits. It implies mutation (adding/removing labels) but does not mention reversibility, permissions, rate limits, or side effects like UI changes. The example hints at usage but is insufficient.

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 sentence that efficiently conveys the core action. It could be restructured to include parameter details, but as is, it is concise and front-loaded.

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 tool has 4 parameters, no output schema, and no annotations, the description is severely incomplete. It fails to explain how to obtain label IDs, the behavior when both add and remove are specified, error handling, or usage across multiple messages.

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?

With 0% schema description coverage, the description must explain parameter meanings. It only indirectly references 'add_label_ids' and 'remove_label_ids' via the example, but does not clarify their format, source, or relation to Gmail labels. Two required parameters (account, message_id) are completely unexplained.

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 'Add/remove' and the resource 'labels on a message', and provides a concrete example ('mark read by removing UNREAD'). This distinguishes it from sibling tools like gmail_message_trash or gmail_send.

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 provides no explicit guidance on when to use this tool versus alternatives (e.g., gmail_message_trash for deletion, gmail_message_get for reading). It lacks context on prerequisites or decision criteria.

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