modify_gmail_message_labels

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

No annotations are provided, so the description carries the full burden. It mentions mutation and provides dry_run for safe preview, but does not detail side effects, permissions required, or irreversibility of actions like adding TRASH. This is adequate but lacks depth on consequences.

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 concise and well-structured, with a clear opening sentence, examples, and a detailed Args section. Every sentence adds value, and the information is 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?

The description covers the main operations, return value (confirmation string), and includes examples. Given the output schema exists, it appropriately explains the return. It is complete for the complexity of the tool.

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?

The description includes an 'Args' section that explains each parameter, including add_label_ids and remove_label_ids which have minimal schema descriptions. This compensates for the 40% schema coverage. The dry_run parameter is clearly explained as a preview without mutation.

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 'Adds or removes labels from a Gmail message' with specific verbs and resource. It provides concrete examples for archiving and deleting, and implicitly differentiates from batch_modify_gmail_message_labels by focusing on a single message.

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 gives explicit usage cases like archiving (remove INBOX) and deleting (add TRASH). It also mentions dry_run for previewing. However, it does not explicitly compare to similar tools like batch_modify_gmail_message_labels or manage_gmail_label, or state when not to use.

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