gmail_get_message

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

Annotations already mark it read-only, idempotent, and non-destructive. The description adds useful behavioral detail by specifying the plain-text body and the exact fields returned. It stops short of a 5 because 'full content' is slightly overbroad and attachments/HTML handling is not addressed.

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 compact sentences with the purpose first and a scannable return list second. No filler or repetition of annotations.

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 simple single-parameter read-only operation, the annotations, and the output schema, the description provides everything needed to call the tool correctly. The only minor gap is explicit sibling routing, which is not essential for invoking this tool.

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 tool description does not mention the message_id parameter, but the input schema's nested property documents it as the Gmail message ID from a list/search result. With that schema coverage, the parameter is adequately explained; the description adds no further semantic meaning.

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 states a specific action ('Get the full content of a single Gmail message') and names the resource (Gmail message), then clarifies the returned body is plain-text. The listed fields (from, to, subject, date, body, labels) distinguish it from siblings like gmail_search_messages and gmail_list_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?

The description implies this is the tool to use when a single message's full content and plain-text body are needed. The schema's message_id description ('from a list/search result') reinforces that the ID comes from a prior search/list, but the description itself does not explicitly name alternatives or state when not to use it.

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