Fastmail MCP Server

delete_email

Delete emails from your Fastmail account. By default, moves to Trash; set permanent=true to permanently erase.

Instructions

Delete an email. By default moves to Trash. Set permanent=true to permanently destroy the email.

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": {
      "emailId": "<emailId>"
    },
    "name": "delete_email"
  }
}

Input Schema

Name	Required	Description	Default
`emailId`	Yes	The email ID to delete
`permanent`	No	Set to true to permanently delete (cannot be undone). Default: move to Trash.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.3.0Aug 2, 2026

TDQS

A4.1/5.0

Behavior4/5

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively communicates that deletion is reversible by default (Trash) and that permanent=true causes irreversible destruction. This is key behavioral information beyond what the input schema alone conveys.

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 concise: two sentences, with the main action first, followed by the optional permanent parameter. Every word adds value, and the structure is clean and front-loaded.

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

Completeness5/5

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

Given the tool's low complexity (2 parameters, no output schema) and the clear description of default vs permanent behavior, the description is comprehensive. It provides all necessary context for an agent to invoke the tool correctly, including the critical distinction between reversible and irreversible deletion.

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?

The input schema already describes both parameters (emailId and permanent) with 100% coverage, including the default and the 'cannot be undone' warning. The description restates this information without adding new semantics beyond the schema. Therefore, a baseline score of 3 is appropriate.

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 the verb 'Delete' and the resource 'email'. It also clarifies the two modes (Trash vs permanent), distinguishing it from sibling tools like archive_email or move_email. The mention of 'permanently destroy' further clarifies the destructive nature when permanent=true.

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

Usage Guidelines3/5

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

The description explains the default behavior (moves to Trash) and the permanent option, which provides usage context for the tool itself. However, it does not explicitly compare against alternatives like archive_email or move_email, or state when not to use this tool. The guidance is implied rather than explicit.

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