get_labels

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

Lacks annotations, so the description carries full disclosure burden. It clarifies scope ('all Gmail labels', 'authenticated user') but omits safety confirmation (read-only nature), rate limits, or whether system labels are included. The return value description is redundant since output schema exists.

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?

Front-loaded action sentence followed by return description. Efficient structure with minimal waste, though the Returns sentence adds limited value given the existence of an output schema.

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?

Adequate for a simple read operation with no parameters and existing output schema. Covers the essential operation scope, though additional context on label types (system vs. user) would improve completeness given zero annotation coverage.

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?

Input schema contains zero parameters. Per rubric, baseline score is 4 for zero-parameter tools. The description implicitly confirms no filtering is possible ('all Gmail labels'), which aligns with 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?

Provides specific verb (Get), resource (Gmail labels), and scope (all labels for authenticated user). However, it does not explicitly differentiate from sibling tools like 'search' or 'list_unread' that might also interact with labels in different contexts.

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?

Offers no guidance on when to invoke this tool versus siblings like 'search' or 'list_unread', nor does it mention prerequisites such as requiring OAuth scopes or when label data is needed for subsequent operations.

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