smtp_send_message

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

There are no annotations, so the description carries the full disclosure burden. It only says it sends an email via SMTP and does not mention that delivery is irreversible, that an authenticated SMTP account may be required, or that external network delivery implies potential rate limits/failure modes.

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 filler words. Everything present is directly useful for purpose, and it does not restate the schema or over-explain.

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?

For a tool this complex (11 parameters, no annotations), the description is minimal and provides little beyond the basic purpose. The schema and output schema fill in almost everything about parameters and return values; the main remaining gap is the broader usage context and side-effect disclosure, which is already reflected in the Usage and Transparency scores.

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 has full coverage of parameter descriptions, so the baseline of 3 applies. The description adds no parameter-specific meaning itself, but the schema descriptions already explain usage, required fields, limits, and attachments, so the agent is not left without parameter guidance.

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 states a specific verb and resource ('send a new email via SMTP'), and the words 'new' and 'SMTP' help distinguish it from reply/forward and from Graph/EWS sending siblings. It does not name sibling tools, but the phrasing is specific enough for an agent to identify the tool's basic role.

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?

Usage is implied by the phrase 'send a new email via SMTP' — the agent can infer it is for new outbound messages rather than replies/forwards. However, there is no explicit when-to/when-not-to guidance and no mention of alternative sending tools like smtp_reply_message, smtp_forward_message, or Graph/EWS senders.

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