Mariana Google MCP

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. While 'List' implies a read-only operation, the description fails to mention authentication requirements, rate limits, pagination behavior, or the structure/format of returned label data.

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 consists of a single efficient sentence with no redundant words. It is appropriately front-loaded with the core action and resource.

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 single-parameter tool, the description meets minimum viability by identifying the core function. However, given the lack of output schema and annotations, gaps remain regarding return format and behavioral constraints that a more complete description would address.

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?

With 100% schema description coverage for the single 'account' parameter, the schema already documents the default behavior. The description adds no parameter-specific context, but baseline 3 is appropriate since the schema is self-sufficient.

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 the verb (List) and resource (Gmail labels/folders) with scope (all, for an account). It implicitly distinguishes from sibling tools like gmail_search or gmail_read by specifying 'labels/folders' rather than messages/emails, though it does not explicitly contrast with alternatives.

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 (e.g., when to list all labels vs searching for specific messages), nor does it mention prerequisites like authentication requirements or default account behavior.

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