Mailercloud plugin for Claude Code

Bundles the Mailercloud MCP server together with ready-made commands, a best-practices skill, and a campaign-manager subagent — so Claude Code users get expert Mailercloud workflows out of the box, not just the raw tools.

This is a Claude Code plugin. For claude.ai / Desktop / Mobile, use the Mailercloud connector in the Claude directory instead — same server, broader reach.

What's inside

Piece	What it adds
`.mcp.json`	Connects the Mailercloud MCP server (`https://mcp.mailercloud.com/mcp`, 47 tools)
`/mailercloud:campaign-audit`	Audit a draft campaign before sending
`/mailercloud:analyze-campaigns`	Analyze recent campaigns + action plan
`mailercloud-best-practices` skill	Tool map, pre-send checklist, deliverability & metric guidance
`campaign-manager` agent	A specialist persona for multi-step campaign work

No changes to the Mailercloud server are required — the plugin only references it.

Install

Run these in Claude Code one at a time (each is a separate slash command — enter the first, wait for it to finish, then enter the second). Do not paste both lines together.

1. Add the marketplace:

/plugin marketplace add https://github.com/mailercloud-com/mailercloud-plugin.git

2. Install the plugin:

/plugin install mailercloud@mailercloud

Use the full https://….git URL above. The GitHub shorthand (mailercloud-com/mailercloud-plugin) makes Claude Code clone over SSH, which fails if you don't have GitHub SSH keys configured. The HTTPS URL works for everyone.

Then restart Claude Code if prompted, and try /mailercloud:campaign-audit.

Install in Gemini CLI

gemini extensions install https://github.com/mailercloud-com/mailercloud-plugin

Then run /mcp in Gemini CLI. mailercloud should be listed, and Gemini will ask you to sign in to Mailercloud the first time a tool runs.

Install in Cline and other MCP clients

Mailercloud is a hosted MCP server at https://mcp.mailercloud.com/mcp (Streamable HTTP, OAuth sign-in). Step-by-step setup for Cline and other agents is in llms-install.md.

Requirements & authentication

A Mailercloud account (sign up at https://mailercloud.com).
The first time a Mailercloud tool runs, Claude Code connects the MCP server and prompts you to authorize — sign in to Mailercloud (OAuth) or provide a Mailercloud API key. Until you authorize, the tools will report that authentication is required; this is expected.

Verify it installed

/plugin list                     # should show: mailercloud@mailercloud

You should also see /mailercloud:campaign-audit and /mailercloud:analyze-campaigns in the slash-command list, and the mailercloud MCP server under your connected tools.

Local development

To test changes without publishing, add the folder as a local marketplace:

/plugin marketplace add ./mailercloud-plugin
/plugin install mailercloud@mailercloud

Structure

mailercloud-plugin/
  .claude-plugin/
    plugin.json          # plugin manifest
    marketplace.json     # makes this repo installable as a marketplace
  .mcp.json              # references the remote Mailercloud MCP server
  commands/              # /mailercloud:* slash commands
  skills/                # mailercloud-best-practices
  agents/                # campaign-manager