gmail_list_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 only says 'List Gmail labels' with no mention of read-only nature, potential side effects, authentication requirements, or response format. This is a minimal, opaque statement that leaves the agent without critical behavioral context.

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 concise sentence with no extraneous information. It front-loads the core action and resource, making it easy to parse and efficient.

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 list tool with one parameter and no output schema, the description is insufficient. It does not indicate what the return value will be (e.g., list of label names, IDs, metadata), nor does it clarify any side effects or permissions. An agent lacks key information needed to confidently call 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?

Schema coverage is 100% with a detailed description of the 'account' parameter (e.g., work, personal, support). The tool description adds nothing beyond the schema, so it meets the baseline for high schema coverage but does not enhance parameter understanding.

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 a specific verb and resource: 'List Gmail labels for an account.' It distinguishes from sibling tools like gmail_list_accounts and gmail_get_profile by naming the exact resource (labels) and scope (account). No ambiguity.

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 guidance on when to use this tool versus alternatives, such as gmail_get_profile or gmail_list_filters. There is no mention of context, prerequisites, or exclusions. An agent must infer the appropriate usage from the tool name alone.

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