ProtonMail MCP Server

send_test_email

Send a test email to verify SMTP configuration and ensure email delivery is working correctly.

Instructions

Send a quick test email to verify SMTP is working

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "to": "<to>"
    },
    "name": "send_test_email"
  }
}

Input Schema

Name	Required	Description	Default
`to`	Yes	Recipient email address
`customMessage`	No	Optional custom message body

Schema Changelog

Changes observed during successful MCP inspections.

First observedv2.0.0May 29, 2026

TDQS

A4.2/5.0

Behavior4/5

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

Annotations already indicate non-read-only and non-destructive behavior. The description adds that it sends a 'quick test email' for SMTP verification, which is consistent with annotations and clarifies the testing nature. No contradiction.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single sentence that is front-loaded with the action and purpose, with no unnecessary words or redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple test tool with full schema coverage and adequate annotations, the description is complete enough. It explains the purpose and scope. There is no output schema, but the return value is likely straightforward (success/failure) and not critical for agent usage.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, with descriptions for both 'to' and 'customMessage'. The description does not add additional meaning beyond what the schema provides; it mentions 'quick test email' but that does not elaborate on parameters.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states 'Send a quick test email to verify SMTP is working', specifying a verb (send), resource (test email), and purpose (verify SMTP). It distinguishes from siblings like 'send_email' and 'send_draft' by emphasizing testing.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies this tool is for testing SMTP rather than regular email sending, but it does not explicitly state when not to use it or name alternatives like 'send_email'. The context is clear but lacks explicit exclusions.

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

Deploy Server