What is MCP and how does flexx use it?

MCP (Model Context Protocol) is an open standard that lets AI agents interact with external tools. flexx turns your machine into an MCP server — AI agents like Cursor, Claude, and ChatGPT can read files, run commands, and edit code on your machine through the relay.

Which AI tools work with flexx?

Any tool that supports the Model Context Protocol (MCP) works with flexx. This includes Cursor, Claude Desktop, ChatGPT with MCP plugins, OpenAI Codex, and any custom MCP client.

Can I use flexx without installing anything?

Yes — for Memory. Create a free account and connect any MCP client; the memory tools need no install and no machine. Remote tools (files, shell, screenshots, tunnels) only become available after you install the flexx CLI on a machine and connect it.

Is my machine exposed to the internet?

No. Your machine only makes outbound WebSocket connections to the relay. Zero inbound ports are opened. The relay mediates all communication between AI agents and your machine.

How do I connect Cursor to my machine via MCP?

Install flexx (curl -fsSL https://cli.flexx.dev/install.sh | sh), run 'flexx setup', then add the MCP server URL https://relay.flexx.dev/v1/mcp in Cursor Settings → MCP → Add Server. OAuth authentication is handled automatically.

Yes. The free tier includes unlimited remotes, unlimited MCP tools, SSH access, and localhost tunneling. Managed and team tiers with additional features are coming soon.

Install flexx CLI

Install the flexx CLI on macOS, Linux, or Windows with one command. This is the step that makes a machine reachable from anywhere — Memory works without it.

Why install the CLI?

Installing the flexx CLI on a machine is what turns it into a remote: after you run flexx setup and flexx connect, that machine is reachable from anywhere over MCP or SSH — no VPN, no port forwarding.

Only need Memory?

You can skip this page. Memory works with just a free account and any MCP client — see Memory. Install the CLI when you want to use a machine remotely.

macOS & Linux

curl -fsSL https://cli.flexx.dev/install.sh | sh

This installs the flexx binary to ~/.flexx/bin and adds it to your PATH.

Pinned version

FLEXX_VERSION=0.14.4 curl -fsSL https://cli.flexx.dev/install.sh | sh

Windows

irm https://cli.flexx.dev/install.ps1 | iex

Installs to %USERPROFILE%\.flexx\bin and adds it to your user PATH.

Verify installation

flexx version

Manual download

Download binaries directly from https://cli.flexx.dev/latest/:

Platform	Binary
Linux (x86_64)	`flexx-linux-amd64`
Linux (ARM64)	`flexx-linux-arm64`
macOS (Intel)	`flexx-darwin-amd64`
macOS (Apple Silicon)	`flexx-darwin-arm64`
Windows (x86_64)	`flexx-windows-amd64.exe`
Windows (ARM64)	`flexx-windows-arm64.exe`

SHA256 checksums are available at https://cli.flexx.dev/latest/checksums.txt.

Update to latest version

flexx update

This downloads the latest binary from cli.flexx.dev and replaces the current one in-place. It does not restart a running daemon — restart the service (or the foreground flexx connect) afterwards.

Next step

After installation, run the setup wizard on the machine you want to reach:

flexx setup      # sign in + register this machine (does not connect)
flexx connect    # bring it online, or: flexx service install

See the Setup guide for details, or jump straight to MCP configuration to connect your AI tool.

Install flexx CLI

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