send_email

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

With no annotations, the description carries full responsibility for behavioral disclosure. It fails to mention that sending is an irreversible side effect, requires an authenticated session, may have rate limits, or that emails can include HTML and attachments. The bare phrase 'Send an email' reveals no behavioral traits.

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 with no extraneous content. It is appropriately concise for the tool's purpose, though its brevity limits detail in other dimensions.

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 complexity (supports HTML, attachments, multiple recipients) and the absence of both annotations and an output schema, the description is insufficiently complete. It does not explain side effects, authentication prerequisites, or error behavior, leaving significant gaps for safe invocation.

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 provides 100% coverage with clear descriptions for all 7 parameters (to, cc, bcc, subject, body, isHtml, attachments). The description adds no additional parameter meaning beyond the schema, so it meets the baseline for high schema coverage.

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 sends an email via an authenticated Gmail account, using the verb 'send' and the resource 'email.' It is specific but does not explicitly differentiate from sibling tools like reply_to_email or create_draft, so it misses the full distinction criterion.

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. The description does not mention exclusions, such as using create_draft for drafts or reply_to_email for replies, and only offers a vague authentication context. This leaves usage decisions entirely to the agent.

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