gmail_list_labels

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safe-read nature is covered. The description adds no behavioral detail beyond the tool name, such as whether all labels are returned, ordering, or account-scoping semantics. It does not contradict the annotations, but it contributes little 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 with no filler. Every word contributes to stating the tool's purpose.

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?

For a simple read-only listing tool, the description is minimally adequate: it names the resource returned. However, with no output schema and no parameter explanation, the agent lacks detail about the profile argument and the shape of the returned label list.

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 0%, and the description does not explain the required 'profile' parameter beyond the phrase 'da conta'. An agent must infer that profile identifies which account's labels to list; no format, allowed values, or default behavior is provided.

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 ('Lista') and resource ('os rotulos/labels') and specifies scope ('da conta'), so an agent knows exactly what the tool does. It is clearly distinct from sibling tools such as gmail_search and gmail_get_message, which operate on messages rather than 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 states the action but gives no guidance about when to choose this tool over alternatives, nor any exclusions or prerequisites. There is no mention that this is the way to discover available labels before searching/filtering messages, which would help route the agent.

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