send_mail

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

With no annotations, the description bears full burden. It discloses key behaviors: sending, filing a copy, default dry_run, and an important provider limitation. Could add error handling details, but current disclosure is solid.

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?

Efficiently structured with purpose, prerequisites, and a safety callout. Every sentence adds value, no fluff.

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?

Covers the main purpose and safety, but with no output schema and many optional parameters undocumented in the description, the agent may miss how to use CC, BCC, attachments, or HTML. Still adequate for a send operation.

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?

With 0% schema description coverage and 9 parameters, the description only adds meaning to from_address (must be configured) and dry_run (default True, safety). CC, BCC, attachments, and html are left unexplained despite being non-trivial.

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?

Clearly states the tool sends mail from configured identities and files a copy in Sent. Distinct from all sibling tools which focus on reading, searching, and listing.

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?

Provides clear prerequisites (from_address must be a configured identity) and limitations (Hotmail/Outlook not supported). Dry_run safety note tells when to actually send. No explicit when-not-to-use, but as the only send tool, this is acceptable.

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