gmail_get_message

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

With no annotations, the description carries the full burden. It accurately indicates a read operation ('Get') and states that headers and body content are included, but does not disclose potential side effects, auth requirements, or the impact of the 'format' parameter. It is minimally transparent but not misleading.

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, front-loaded sentence that immediately conveys the tool's purpose without filler words. Every word contributes meaning, making it highly concise and well-structured.

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?

Given the simplicity of the tool and full schema coverage, the description adequately covers the core functionality. However, the absence of an output schema and lack of guidance about the 'format' enum's effect on return value leaves some gaps. It is sufficient but not rich.

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 fully describes all three parameters (accountId, messageId, format) with 100% coverage. The description adds no additional parameter-specific meaning beyond noting 'by ID', which is already covered by the schema. Baseline 3 is appropriate because the schema does the heavy lifting.

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 'Get' and the resource 'a single Gmail message by ID', making its purpose specific and unambiguous. It also differentiates from siblings like gmail_get_messages_batch and gmail_get_thread by emphasizing 'single' and including 'headers and body content'.

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 implies use for retrieving one message at a time but does not explicitly contrast with alternatives like batch retrieval or thread retrieval. There is no mention of when to choose this tool over gmail_get_messages_batch or gmail_get_thread, leaving the guidance mostly implied.

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