@maxedapps/pi-ssh-session

A Pi package that keeps a persistent OpenSSH ControlMaster connection and routes Pi's built-in file and shell tools to a remote host.

Connect once, work with Pi's normal tools on the remote machine, and disconnect when you want to return to local execution. The SSH connection is held in memory for the active Pi session.

Security

Pi packages execute with your full user permissions. This extension can run arbitrary shell commands and read or modify files on the selected remote host. Local forwarding also opens listening ports on your machine.

Review the package source, SSH target, remote working directory, and forwarding specifications before connecting. OpenSSH performs its normal host-key verification; this package does not add a separate trust, authentication, or authorization layer.

Requirements

Local machine

• Node.js 22.19.0 or newer
• Pi
• An OpenSSH-compatible ssh client
• Non-interactive SSH authentication, such as SSH keys or an SSH agent

Password and other interactive authentication prompts are not supported because connections use OpenSSH batch mode.

Remote host

• bash for remote commands
• rg (ripgrep) for Pi's grep tool
• fd for Pi's find tool
• file for image MIME detection by Pi's read tool (optional)
• Standard commands such as cat, mkdir, and ls

A connection can still open without rg, fd, or file, but the corresponding capability is unavailable.

Install

Install globally through Pi:

pi install npm:@maxedapps/pi-ssh-session

Install for the current project instead:

pi install -l npm:@maxedapps/pi-ssh-session

Try the package for one Pi run without installing it:

pi -e npm:@maxedapps/pi-ssh-session

You can also install directly from Git:

pi install git:github.com/maxedapps/pi-ssh-session

Pi reads the package manifest and loads src/pi-ssh-session.ts directly through Jiti. No build output is required.

Connect

Startup flags

| Flag | Purpose | |---|---| | --ssh <target> | Connect on startup. Accepts an SSH host alias, user@host, or a target with a remote path such as user@host:/srv/app. | | --ssh-dir <path> | Set or override the remote working directory used with --ssh. | | --ssh-forwards <specs> | Add comma-separated local forwards in localPort:host:hostPort form. |

Examples:

pi --ssh my-vps --ssh-dir /srv/app
pi --ssh user@host:/srv/app --ssh-forwards 15432:127.0.0.1:5432

Slash commands

/ssh-connect <target> [remote-dir] [--forwards localPort:host:hostPort,...]
/ssh-status
/ssh-disconnect

Examples:

/ssh-connect my-vps
/ssh-connect my-vps /srv/app
/ssh-connect user@host:/srv/app --forwards 15432:127.0.0.1:5432

• /ssh-connect opens a connection, switches hosts, or updates the working directory for the current target.
• /ssh-status reports the target, directory, forwards, detected capabilities, and control socket.
• /ssh-disconnect closes SSH and restores local tool execution.

ssh_session agent tool

The package registers an agent-callable ssh_session tool:

| Action | Behavior | |---|---| | connect | Open or switch a session. target is required unless a target is already configured. Optional remoteCwd and forwards override configured values. | | status | Return the current local, configured, or connected state. | | disconnect | Close SSH and return Pi's built-in tools to the local machine. |

Example tool input:

{
  "action": "connect",
  "target": "user@host:/srv/app",
  "remoteCwd": "/srv/app",
  "forwards": ["15432:127.0.0.1:5432"]
}

The agent should call ssh_session in its own step before using remote tools and disconnect before returning to local files or commands.

Core tool routing

While connected, the package overrides Pi's normal tools with remote operations. Tool names and input shapes remain unchanged.

| Pi feature | Remote behavior | Remote requirement | |---|---|---| | read | Reads remote files and detects supported image types | cat; optional file for image MIME detection | | write | Creates parent directories and writes remote files | mkdir, cat | | edit | Reads and writes remote files through Pi's normal edit behavior | cat, mkdir | | bash | Runs commands in the mapped remote working directory | bash | | ls | Lists remote files and directories | ls | | find | Performs remote glob searches | fd | | grep | Searches remote content and preserves Pi-compatible result formatting | rg | | User ! commands | Executes user shell commands through the active SSH connection | bash |

When SSH is disconnected, all of these features use Pi's original local operations.

Forwarding

Each forward uses OpenSSH local-forwarding syntax:

localPort:host:hostPort

The startup flag and slash command accept comma-separated specifications. The ssh_session tool accepts an array. Empty entries are ignored, exact duplicates are removed while preserving order, and invalid specifications are rejected.

Examples:

pi --ssh my-vps --ssh-forwards 15432:127.0.0.1:5432

/ssh-connect my-vps --forwards 15432:127.0.0.1:5432,16379:127.0.0.1:6379

Connections with forwards use OpenSSH's ExitOnForwardFailure=yes, so connection setup fails if a requested forward cannot be opened.

Connection lifecycle

The package:

1. starts an OpenSSH ControlMaster when a connection is requested;
2. resolves the remote working directory;
3. detects remote rg, fd, and file capabilities;
4. routes Pi's core file and shell tools through the active control connection;
5. keeps the desired connection configuration in memory and attempts to reconnect before a remote tool call if the master closes unexpectedly;
6. updates Pi's status and system prompt with the active remote target;
7. closes the control connection on explicit disconnect or Pi session shutdown.

Connection state is not persisted across session replacement, reloads, or Pi runs.

Troubleshooting

Authentication fails or prompts for a password

Confirm that the target works non-interactively outside Pi:

ssh -o BatchMode=yes user@host true

Configure SSH keys, your SSH agent, and ~/.ssh/config as needed. Interactive password, passphrase, and keyboard-interactive prompts cannot be handled by the extension.

Host-key verification fails

Connect with OpenSSH directly and verify the host fingerprint. Do not bypass host-key checking for an untrusted host.

grep or find fails after connecting

Install rg for grep and fd for find on the remote host. /ssh-status and ssh_session status output show detected capabilities.

Image detection is unavailable

Install file on the remote host. Text and binary file reading can still work without image MIME detection.

A local forward cannot be opened

Check whether the local port is already in use and whether the destination host and port are reachable from the remote machine. The SSH connection intentionally fails when forward setup fails.

The control connection closes

The package keeps the requested configuration and attempts to reconnect before the next remote tool call. Use /ssh-status, reconnect explicitly, or /ssh-disconnect to return to local execution.

Update or remove

Update the package:

pi update npm:@maxedapps/pi-ssh-session

Remove it:

pi remove npm:@maxedapps/pi-ssh-session

Use -l with pi install or pi remove when managing project-local package settings.

Development

git clone https://github.com/maxedapps/pi-ssh-session.git
cd pi-ssh-session
corepack enable
pnpm install --frozen-lockfile
pnpm typecheck
pnpm test
pnpm check

Load the local checkout in isolation:

pi --no-extensions -e . --help

Tests are deterministic and require no network access, credentials, or SSH host. Real-host SSH integration is not part of the normal test suite.

Maintainers should follow RELEASING.md for the manual npm release process. This project does not publish from CI.

License and attribution

MIT licensed. Portions are derived from Pi's official SSH extension example, Copyright (c) 2025 Mario Zechner. See LICENSE and NOTICE.