How to add human approval to a Claude agent with MCP in 5 minutes
Step-by-step: connect the redphonr MCP server to Claude Code, Claude Desktop or Cursor, and make your agent ask you on Slack or SMS before risky actions.
Human-in-the-loop for AI agents
redphonr
Human approvals for AI agents, over MCP
redphonr pauses an AI agent before a risky action, asks a person on Slack, SMS, WhatsApp, Telegram, Discord, email or a phone call, and resumes the agent with their answer.
What redphonr does
One tool call
Agents call request_approval, ask_human, collect_input or verify_output from any MCP client: Claude, Cursor, the OpenAI Agents SDK, LangChain, CrewAI and more.
Seven channels
Slack, SMS, WhatsApp, Telegram, Discord, email and voice calls. On a call, press 1 to approve or 2 to deny.
Escalation and on-call
If nobody answers, redphonr moves down the ladder and on to whoever is on call, then their backup. Weekly rotations with overrides.
Safe by default
Requests deny on timeout, one answer closes the request on every channel, and every decision is logged.
Start here
Frequently asked questions
What is redphonr?
redphonr is a human-in-the-loop service for AI agents. It runs as an MCP server: an agent calls a tool such as request_approval, pauses, and resumes with the person’s decision as structured data.
Which agents work with redphonr?
Any MCP-capable agent, including Claude Desktop, Claude Code, Cursor, Windsurf, the OpenAI Agents SDK, LangChain, CrewAI, Mastra and AutoGen. Agents without MCP can use the HTTP API.
Is redphonr free?
redphonr is free to start and does not need a credit card.
More about redphonr on the blog
All posts on the blogThe 10 best human-in-the-loop tools for AI agents in 2026
We compared 10 ways to add human approval to AI agents: managed services, workflow tools and framework features. Channels, MCP support and when to use each.
Top 10 ways to get alerted when your AI agent needs a human
From MCP-native escalation to PagerDuty, Twilio and Slack webhooks: 10 ways an AI agent can reach a person, ranked by how well they get an answer back.