Microsoft 365 Mail MCP Server

What the code does

We read the source, 22 h ago · rules 995398eba69f

A value the model can set ends up inside a file or shell call. That is not a flaw by itself — for a terminal server it is the job — but it is where things go wrong when it is not.

          fs.writeFileSync(outFd, pdfBuffer);

What this server is able to do. For an MCP server this is often the job itself — a terminal server runs commands because that is what it is for. Listed so you know what you are plugging in, not as an accusation.

  const fullPath = path.join(stagingDir, filename);

    const child = spawn(process.execPath, [script], {

  if (isUnder(resolvedAbs, sshDir)) return { hit: true, reason: '~/.ssh/** is sensitive' };

  <script src="https://appsforoffice.microsoft.com/lib/1.1/hosted/office.js"></script>

    const entries = fs.readdirSync(workspacePath, { withFileTypes: true });

Is this your server and something here is wrong? Tell us — corrections are free and do not require a plan.

Connect this server

This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.

claude mcp add mcp-server-microsoft-mail -e 'MS_CLIENT_ID=<MS_CLIENT_ID>' -e 'MS_CONFIG_DIR=<MS_CONFIG_DIR>' -- npx -y @mindstone/mcp-server-microsoft-mail

{
  "mcpServers": {
    "mcp-server-microsoft-mail": {
      "command": "npx",
      "args": [
        "-y",
        "@mindstone/mcp-server-microsoft-mail"
      ],
      "env": {
        "MS_CLIENT_ID": "<MS_CLIENT_ID>",
        "MS_CONFIG_DIR": "<MS_CONFIG_DIR>"
      }
    }
  }
}

[mcp_servers.mcp-server-microsoft-mail]
command = "npx"
args = ["-y", "@mindstone/mcp-server-microsoft-mail"]
env = { MS_CLIENT_ID = "<MS_CLIENT_ID>", MS_CONFIG_DIR = "<MS_CONFIG_DIR>" }

{
  "mcpServers": {
    "mcp-server-microsoft-mail": {
      "command": "npx",
      "args": [
        "-y",
        "@mindstone/mcp-server-microsoft-mail"
      ],
      "env": {
        "MS_CLIENT_ID": "<MS_CLIENT_ID>",
        "MS_CONFIG_DIR": "<MS_CONFIG_DIR>"
      }
    }
  }
}

{
  "servers": {
    "mcp-server-microsoft-mail": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@mindstone/mcp-server-microsoft-mail"
      ],
      "env": {
        "MS_CLIENT_ID": "<MS_CLIENT_ID>",
        "MS_CONFIG_DIR": "<MS_CONFIG_DIR>"
      }
    }
  }
}

Put your own values in place of <MS_CLIENT_ID> (Microsoft Entra (Azure AD) application client ID), <MS_CONFIG_DIR> (Path to the per-user Microsoft config directory (credentials/, accounts.json)). The author’s registry entry marks them as required.

Optional settings from the registry entry, left out of the block above: MS_ACCOUNT_EMAIL (Account email when running in multi-account per-instance mode (falls back to the first account in accounts.json)), MS_MCP_PACKAGE_ID (Logical package ID surfaced in error responses), MICROSOFT_REQUEST_TIMEOUT_MS (Override the upstream Microsoft Graph request timeout in milliseconds (max 300000 = 5 min)), MCP_WORKSPACE_PATH (Workspace root where download_attachment saves files (falls back to the OS temp directory when unset)).