Send an email by entering the recipient address, subject, and body. The message is delivered via SMTP from the conversation.
Send an email via SMTP
| Name | Required | Description | Default |
|---|---|---|---|
| to | Yes | Recipient email address | |
| body | Yes | Email body content | |
| subject | Yes | Email subject |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must disclose behavioral implications. It reveals the action and the SMTP protocol but does not mention that sending is an external side effect, cannot be undone, requires authorization, or what result the caller should expect.
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 sentence with no filler or repetition. It is front-loaded with the core action ('Send an email') and adds the useful protocol qualifier 'via SMTP' without unnecessary detail.
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?
This is a minimally viable description for a simple tool with fully documented required parameters. However, there is no output schema and no annotations, so the agent is left uninformed about return values, error behavior, delivery guarantees, or side effects of sending an email.
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 already documents all three parameters with a description coverage of 100%, establishing baseline clarity. The description adds no additional parameter meaning or constraints beyond what the schema provides.
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 an email via SMTP'. This clearly distinguishes it from the sibling tools: get_unread_emails is a read operation and create_draft_reply only creates a draft rather than sending it.
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 gives no guidance on when to use this tool instead of create_draft_reply or get_unread_emails. There are no conditions, exclusions, or alternative-tool hints provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.