Best MCP servers for phone calls and messaging
7 working options, checked Nov 8, 2026.
Short answer: the top picks for phone calls and messaging right now are Slack, CosVoice and DialValet. We list 7 options here: 3 work without sign-in, 3 need a sign-in and 1 run on your own machine.
These MCP servers let an AI assistant reach people outside email: post in Slack, send WhatsApp messages, place real phone calls or even send a fax. Because they contact real people, approval settings matter more here than almost anywhere else.
Top picks
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Slack
Read channels, search history, and post messages in Slack.
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CosVoice
CosVoice gives your AI Chief of Staff (Grok Bot, Claude, ChatGPT, Cursor) a real US phone number and email. It calls, answers, and sends written summaries. Connect via https://cosvoice.com/mcp — from $29/mo.
Tools include
get_account,search_numbers,create_line,get_line,place_call -
DialValet
U.S. outbound calls FROM your verified personal number for AI agents (CLI/MCP).
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fone.me
AI agent that answers your phone when you can't
Tools include
find_agents,get_agent,message_agent,add_chat_to_website -
TaskBullet
Let AI agents place real phone calls (a human makes the call and returns structured answers) and hand off other tasks to human VAs.
Tools include
understand_site,match_intent,list_services,get_pricing,recommend_path
All 7 compared
| Server | What it does | Setup | Tools |
|---|---|---|---|
| Slack | Read channels, search history, and post messages in Slack. | Runs locally | – |
| CosVoice | CosVoice gives your AI Chief of Staff (Grok Bot, Claude, ChatGPT, Cursor) a real US phone number and email. It calls, answers, and sends written summaries. Connect via https://cosvoice.com/mcp — from $29/mo. | Hosted, no sign-in | 27 |
| DialValet | U.S. outbound calls FROM your verified personal number for AI agents (CLI/MCP). | Hosted, sign-in | – |
| fone.me | AI agent that answers your phone when you can't | Hosted, no sign-in | 4 |
| TaskBullet | Let AI agents place real phone calls (a human makes the call and returns structured answers) and hand off other tasks to human VAs. | Hosted, no sign-in | 5 |
| Whatsable WhatsApp Business Agent Skills | Agent Skills for WhatsApp Business automation via Whatsable. | Hosted, sign-in | – |
| mcpfax | Send real faxes worldwide from Claude, ChatGPT & Cursor. Prepaid, no subscription, PDF report. | Hosted, sign-in | – |
How to choose
- Team chat or the outside world? Slack stays inside your company. Phone and WhatsApp reach customers, so keep a person in the loop.
- AI voice or a human caller? Some servers use an AI voice, while others have a real person make the call and report back.
- Know the rules. Automated calls and messages are regulated in many countries, so check consent rules before using them with customers.
How to connect one
Here is CosVoice as an example. In Claude Code, run:
claude mcp add --transport http cosvoice https://cosvoice.com/mcpFor other apps, follow our guides for Claude, ChatGPT, Cursor and VS Code.
How we picked these
We read each listing's tools and put the closest fit for this job first. Hosted servers must pass a real MCP handshake in our daily check to stay on this page, and local servers are reviewed from their source or package. That shows a server responds, not how well it works for you, and we don't run every tool in production.
Frequently asked questions
Which of these MCP servers work without signing in?
CosVoice, fone.me and TaskBullet answered our latest live check with no account or key.
Can an AI agent make phone calls through MCP?
Yes. Several servers place real outbound calls, either with an AI voice or with a human who calls and returns a structured answer.
How do I connect Slack to an AI assistant?
Add a Slack MCP server, then authorize it for your workspace. It can then read channels, search history and post messages, limited to the permissions you grant.
How often is this list updated?
Every hosted server here is re-checked daily with a real MCP handshake, and a server drops off this page while it fails that check. Last check: Nov 8, 2026.