get_labels

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

With no annotations provided, the description carries the full burden. It does disclose the return fields (label IDs, names, message counts) and notes both system and user labels, which is useful. However, it does not explicitly state read-only behavior, pagination, limits, or authentication requirements, leaving some behavioral aspects undisclosed.

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 is direct and front-loaded. It states the action, the resource, examples, and the return payload without any wasted words.

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 tool is simple with no parameters and no output schema. The description fully covers what it returns and the scope of labels (system and user), which is sufficient for an agent to invoke it confidently. There are no missing prerequisites or hidden side effects.

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?

There are zero parameters, so the baseline is 4. The description adds meaningful context by specifying that all labels are returned, eliminating ambiguity about what the tool covers. No parameter documentation is needed since the schema is empty.

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 uses a specific verb 'List' and identifies the resource as 'Gmail labels', clearly distinguishing it from sibling tools like set_labels. It further clarifies the scope by including both system labels (INBOX, SENT) and user-created labels.

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 when you need to see all labels and their IDs/names/counts, but it does not explicitly contrast with alternatives or state when not to use it. There is no mention of sibling tools or exclusions, so guidance is implied rather than explicit.

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