ni-c/smtp-mcp

Overview

MCP server for sending email over SMTP. It restricts recipients via an allowlist and requires a human confirmation step before any message is sent.

Best for

Best for
Developers who want a safe, human-approved email sending path for MCP agents

Use cases

• Send email from an AI assistant via MCP
• Restrict outbound mail to approved recipients
• Add a human-in-the-loop approval step to automated emails

How to use

Install

claude mcp add smtp -- npx -y @ni-c/smtp-mcp

Tools exposed

• SMTP_HOST
• SMTP_USER
• SMTP_PASSWORD
• SMTP_FROM
• SMTP_REPLY_TO
• SMTP_PORT
• SMTP_TLS
• SMTP_ALLOW_SEND
• SMTP_ALLOWED_RECIPIENTS
• SMTP_MAX_RECIPIENTS
• SMTP_MAX_SENDS_PER_HOUR
• SMTP_MAX_MESSAGE_BYTES
• SMTP_MAX_ATTACHMENT_BYTES
• SMTP_ATTACHMENT_DIR
• SMTP_ATTACHMENT_TYPES
• SMTP_SIGNATURE
• SMTP_AUDIT_LOG
• SMTP_ALLOW_TOOLS
• SMTP_DENY_TOOLS
• SMTP_INSECURE_TLS

Tested with

Claude Desktop, Claude Code, Cursor, ChatGPT

Notes

MCP server for sending email over SMTP. It restricts recipients via an allowlist and requires a human confirmation step before any message is sent.

0 stars on GitHub. Last updated 2026-09-07. Licensed MIT.

Use cases

• Send email from an AI assistant via MCP
• Restrict outbound mail to approved recipients
• Add a human-in-the-loop approval step to automated emails

Pros

• Allowlist prevents sending to unapproved addresses
• Human confirmation adds a safety check before dispatch
• Uses standard SMTP, so it works with existing mail servers

Cons

• No community adoption or stars yet
• Human confirmation step blocks fully autonomous workflows
• SMTP-only, so no native support for transactional email APIs

Indexed from awesome-mcp-servers-punkpeye and enriched against its public facts.