gmail_send_email

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

With no annotations, the description bears full burden but only states it sends an email. It does not disclose mutation effects, rate limits, size constraints, or that it creates a sent email. Minimal behavioral disclosure.

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 uses a clear bulleted list under 'Args' and is relatively concise. However, the subject field has an empty description, which wastes space.

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 5 parameters and an output schema, the description fails to mention the output schema, attachments (not supported?), or error cases. The contradiction on required fields further undermines completeness.

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 coverage is 0%, so description must compensate. It provides brief parameter descriptions (e.g., comma-separated addresses, HTML flag) but contradicts the schema by marking to, subject, body as required when schema has zero required parameters. Subject description is empty. Incomplete and inaccurate.

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 from the connected Gmail account. It uses a specific verb ('send') and resource ('email'), and differentiates from sibling Gmail tools like list and get.

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 on when to use this tool versus alternatives (e.g., gmail_modify for drafts). The description merely states the action without specifying when or 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.