confirm-mcp

An MCP server that gives any MCP-compatible agent (Claude Desktop, Cursor, and others) a human-approval tool. Before the agent does something irreversible, it calls request_approval, a human approves or edits the action at confirm.dev, and the agent proceeds with the approved result. Every decision is logged.

Setup

Get an API key at confirm.dev, then add the server to your MCP client config.

Claude Desktop (claude_desktop_config.json):

{
  "mcpServers": {
    "confirm": {
      "command": "npx",
      "args": ["-y", "confirm-mcp"],
      "env": { "CONFIRM_API_KEY": "cfm_live_..." }
    }
  }
}

That's it. The agent now has two tools.

Related MCP server: final-approval

Tools

request_approval

Pause and ask a human to approve a sensitive action. Blocks until the human decides or the wait elapses.

On APPROVED, the tool returns the effectivePayload to use (the human may have edited it). On REJECTED or EXPIRED, it tells the agent to stop. If the wait elapses while still pending, it returns the request id so the agent can poll later.

check_approval

Poll a previously created request by id to see whether a human has decided.

Why a tool, not a prompt

The approval is enforced server-side: the agent cannot fake a verdict, and every decision is recorded in an immutable audit log. Teaching the agent when to call this (via a system prompt or an agent skill) is the coverage layer; the tool is the enforcement layer.

For production agents where you need guaranteed coverage of specific actions, use the deterministic policy engine in @confirm/sdk (guard()) rather than relying on the model to remember to call the tool.

Docs: confirm.dev/docs. Node 18+.

Development

This package is developed in a private monorepo alongside the Confirm.dev service and mirrored here on every release, which is why the history starts at the first public release. Issues and PRs are welcome; PRs get cherry-picked upstream.

Build: npm install && npm run build. Test: node smoke.mjs (after a build; uses a mocked client, no network).