send_email

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

The description correctly indicates a write operation (sending), matching readOnlyHint=false. However, it does not disclose other behavioral details such as saving to Sent folder or rate limits, given openWorldHint=true.

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?

A single sentence of 11 words, no redundancy. Front-loaded with the core action, appropriately sized for a straightforward task.

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?

The description covers the main action and features but does not mention what the output or response is, nor does it set expectations for side effects like saving to Sent or delivery confirmation. Given 9 parameters and no output schema, a bit more context would be helpful.

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 description lists feature groups (CC, BCC, HTML, priority, attachments) that correspond directly to schema parameters. With 100% schema coverage and individual parameter descriptions, the tool description adds no new semantics beyond grouping.

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 it sends an email via ProtonMail SMTP and lists key features (CC, BCC, HTML, priority, attachments). It distinguishes from sibling tools like create_draft by implying immediate sending.

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 like create_draft or send_draft. It does not mention prerequisites or context for appropriate use.

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