email_labels

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

The description implies a read-only, safe operation, but no annotations exist to confirm. It provides no details about hidden behaviors (e.g., system labels included, pagination, permissions). Adequate for a simple list, but lacks depth.

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?

Single sentence, front-loaded with key information. No wasted words. Efficient and clear.

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 basic purpose, but given no output schema, it should hint at the return value (e.g., list of label names or objects). The agent might not know what to expect. Otherwise, adequate for a simple list operation with no parameters.

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 input schema has no parameters (0 params), so baseline is 4. The description adds value by clarifying that labels are also known as 'folders/tags', which aids the agent in understanding the resource type. This goes beyond the empty schema.

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 'List all Gmail labels (folders/tags).' This specifies the action (list), resource (Gmail labels), and adds clarifying terms (folders/tags). It distinguishes this tool from sibling tools like email_create_label or email_add_label, which involve modifying 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?

No guidance is provided on when to use this tool versus alternatives. For instance, it doesn't mention prerequisites (e.g., authentication) or typical workflows (e.g., listing labels before applying one). The agent has no context for appropriate use.

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