send_message

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

With no annotations provided, the description carries the full burden. It discloses that dry_run defaults to true (preview only) and must be set to false to send. It also notes the no-attachments constraint. While it does not detail all edge cases or output, the major behavioral traits are effectively communicated.

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?

Three concise sentences. First sentence states purpose and constraint, second explains dry-run behavior, third provides alternative for attachments. Every sentence earns its place with no redundancy.

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 8 parameters (3 required), no annotations, but an output schema exists (though not shown), the description covers core behavior, constraints, and an alternative workflow. It does not explain output or errors, but the output schema mitigates that. For a standard send tool, it is sufficiently complete.

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 description coverage is 0%, so the description must compensate. It adds meaning for the dry_run parameter (default true, must set false to send) and implies the role of to, subject, body. However, it does not describe cc, bcc, send_as, account_id, leaving those parameters with only their names for context. Partial but incomplete compensation.

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 'compose and send', the resource 'email', and a key constraint 'no attachments'. It also distinguishes from sibling tools by directing users to an alternative pipeline for 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?

The description provides explicit when-to-use (sending plain emails) and when-not-to-use (attachments), along with a specific alternative (create_draft + add_attachment_to_draft + manage_draft). It also explains the dry-run behavior and how to actually send.

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