gmail_read_message

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

There are no annotations, and the description does not disclose side effects such as whether the message is marked as read, nor does it describe return content characteristics beyond 'full content'. The burden of behavioral disclosure falls entirely on the description, which it fails to meet.

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 sentence with no unnecessary words. It is front-loaded with the action and resource, making it extremely concise and easy to parse.

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 tool's simplicity and the presence of an output schema, the description provides the essential purpose but lacks context about usage scenarios, such as whether attachments are included or if special permissions are needed. It is minimally viable but not enriched.

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 schema has 0% description coverage, and the description only adds 'by its ID' to imply that message_id is the Gmail message identifier. This is minimal compensation; it does not explain ID format, how to obtain it, or any constraints on the value.

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's function: 'Read the full content of a Gmail message by its ID.' It uses a specific verb ('Read') and resource ('Gmail message'), and 'by its ID' distinguishes it from reading threads or attachments.

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?

No guidance is provided on when to use this tool versus alternatives like gmail_read_thread or gmail_get_attachment. It does not mention exclusions, prerequisites, or when other tools would be more appropriate.

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