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sendsets

v1.0.0

Cold email for AI agents: connect and warm up sending mailboxes, turn a lead list into an outbound sequence, send a test, launch, and read and answer replies.

CodexClaude CodeAgent Plugins3 Skills1 MCP serverStreamable HTTP

By SendsetsLicense: Apache-2.01 GitHub starsUpdated yesterday

Directory evidence

Runtimes
Codex, Claude Code, and Agent Plugins
Parsed components
4 skill or MCP entries
Source updated
Sep 27, 2026
Manifest status
Canonical path parsed

The directory validates manifest shape and source location. It does not execute the plugin or provide a security endorsement. Review the indexing methodology →

Install sendsets for Codex and Claude Code

Installs for the current user
codex plugin marketplace add AddisonHoff/sendsets
codex plugin marketplace upgrade sendsets
codex plugin add sendsets@sendsets

Paste and run these commands in a terminal with Codex. They add and refresh the sendsets catalog, then install this plugin.

Compatibility: the page URL and API slug “sendsets” remain stable.

  • Codex: sendsets@agent-plugin-marketplace → sendsets@sendsets

The installer fetches third-party code from the source repository shown on this page. This directory validates manifest structure and source location, but does not perform a security audit; review the manifest, components, and source before installing.

Get the source manually
git clone https://github.com/AddisonHoff/sendsets

Clone the source repository, then follow its setup instructions to add the plugin to a compatible client. The repository root is the plugin root.

Plugin files

sendsets/
├── .codex-plugin/plugin.json
├── .claude-plugin/plugin.json
├── plugin.json
├── skills/send-cold-email/SKILL.md
├── skills/sendsets/SKILL.md
├── skills/sendsets-cli/SKILL.md
└── .mcp.json

Included Skills3

send-cold-emailskills/send-cold-email/SKILL.md

Send cold email and run outbound email campaigns from an agent with Sendsets. Connect or check sending mailboxes, turn a lead list (CSV or inline) into a multi-step email sequence with follow-ups, validate merge fields, send a test, launch, and read and answer replies. Use when the user asks to send cold emails, email a list of prospects or leads, run an outreach or outbound sequence, or follow up with contacts by email.

sendsetsskills/sendsets/SKILL.md

Use Sendsets to turn a software product into useful outbound campaigns, then operate mailboxes, warmup, campaigns, replies, and product integrations through the CLI. Use when the user asks to set up or run cold email with Sendsets or wants campaign ideas grounded in their codebase.

sendsets-cliskills/sendsets-cli/SKILL.md

Use the `sendsets` CLI to drive SendSets as a signed-in user - sign in with `sendsets login`, run `sendsets doctor`, then connect the app (`connection`), add or test mailboxes and their warmup (`mailbox`), send product events (`events send`), and build, validate, test and launch campaigns, including app_action and wait_for_event steps, on the hosted service or any self-hosted instance. Use whenever the task is to set up or operate SendSets from a terminal or a script and a `sendsets` binary is available, with no dashboard. For instance recovery and accounts (database-level), use sendsets-ops instead.

MCP servers1

sendsetsStreamable HTTP
url
https://api.sendsetsapi.com/v1/mcp

Plugin manifests3

.codex-plugin/plugin.json
{
  "name": "sendsets",
  "version": "1.0.0",
  "description": "Cold email for AI agents: connect and warm up sending mailboxes, turn a lead list into an outbound sequence, send a test, launch, and read and answer replies.",
  "author": {
    "name": "Sendsets",
    "url": "https://sendsetsapi.com"
  },
  "homepage": "https://sendsetsapi.com",
  "repository": "https://github.com/AddisonHoff/sendsets",
  "license": "Apache-2.0",
  "keywords": [
    "cold-email",
    "outbound",
    "email",
    "sales",
    "campaigns",
    "warmup",
    "mcp"
  ],
  "skills": "./skills/",
  "mcpServers": "./.mcp.json",
  "interface": {
    "displayName": "Sendsets",
    "shortDescription": "Cold email for AI agents",
    "longDescription": "Run cold email from Codex. Connect mailboxes, warm them up, build and launch outbound campaigns, add leads, and handle replies. Send actions go through an approval policy.",
    "developerName": "Sendsets",
    "category": "Sales",
    "capabilities": [],
    "defaultPrompt": [
      "Send a three-step cold email sequence to the leads in leads.csv, and send me a test first"
    ],
    "logo": "./assets/logo.png",
    "screenshots": [],
    "websiteURL": "https://sendsetsapi.com",
    "privacyPolicyURL": "https://sendsetsapi.com/privacy",
    "termsOfServiceURL": "https://sendsetsapi.com/terms",
    "supportURL": "https://sendsetsapi.com/contact"
  }
}
.claude-plugin/plugin.json
{
  "name": "sendsets",
  "version": "1.0.0",
  "description": "Cold email for AI agents. Connects the Sendsets MCP server (OAuth sign-in) and adds skills for turning your product into outbound campaigns and operating mailboxes, warmup, campaigns and replies through the sendsets CLI.",
  "author": {
    "name": "Sendsets",
    "email": "[email protected]",
    "url": "https://sendsetsapi.com"
  },
  "homepage": "https://sendsetsapi.com",
  "repository": "https://github.com/AddisonHoff/sendsets",
  "license": "Apache-2.0",
  "keywords": [
    "cold-email",
    "outbound",
    "email",
    "sales",
    "mcp",
    "campaigns",
    "warmup",
    "deliverability",
    "lead-generation"
  ]
}
plugin.json
{
  "$schema": "https://agent-plugins.org/schemas/1.0.0/plugin.schema.json",
  "name": "sendsets",
  "version": "1.0.0",
  "description": "Cold email for AI agents: the Sendsets MCP server plus skills for sending cold email sequences and running outbound campaigns.",
  "author": {
    "name": "Sendsets",
    "email": "[email protected]",
    "url": "https://sendsetsapi.com"
  },
  "homepage": "https://sendsetsapi.com",
  "repository": "https://github.com/AddisonHoff/sendsets",
  "license": "Apache-2.0",
  "keywords": [
    "cold-email",
    "outbound",
    "email",
    "sales",
    "campaigns",
    "warmup",
    "mcp"
  ]
}

For maintainers

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[sendsets on Agent Plugins Marketplace](https://pluginsmp.com/plugins/sendsets)