gmail_get_messages_batch

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

No annotations are provided, so the description carries full behavioral burden. It mentions the 50-message limit, but this duplicates the schema's 'max 50' constraint. It does not disclose read-only status, error behavior, response format details, or any other side effects, leaving the agent with insufficient information for safe invocation.

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 two sentences, front-loaded with the core action, and every word earns its place. It is concise and structured effectively, though the limit mention is redundant with the schema, it does not hurt clarity.

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?

There is no output schema, yet the description does not explain the return value shape or the meaning of the format enum values. It conveys the core purpose and limit, but lacks completeness for a batch operation where the response structure and format semantics are important.

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 100%, with each parameter having a clear description. The tool description adds no additional meaning beyond the schema, so the baseline of 3 is appropriate.

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 tool fetches multiple Gmail messages in a single call, with a specific verb ('Fetch') and resource ('Gmail messages'). It distinguishes from single-message fetch tools like gmail_get_message by emphasizing batch efficiency and the 50-message limit.

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 phrase 'More efficient than fetching individually' implies use when multiple messages are needed, providing clear context for preferring this over gmail_get_message. However, it does not explicitly name alternatives or state when not to use it, so it falls short of explicit when/when-not guidance.

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