The SSH client for AI agents and humans. Connect by name. Reuse authenticated SSH connections. Keep secrets local.

AI agents don't use SSH the way humans do. Plain SSH exposes credentials to the caller, returns terminal text that agents must parse, re-authenticates every command, and relies on tmux, nohup, or custom scripts for long-running tasks.

Corv is built for agent-driven infrastructure. It lets agents connect by name, execute commands without exposing passwords or private keys, receive structured JSON output, reuse a warm authenticated connection, and detach and resume long-running jobs. Humans use the exact same connections through an interactive terminal UI.

Install

Linux / macOS

curl -fsSL https://raw.githubusercontent.com/khalid-src/corv-client/main/install.sh | sh

Windows (PowerShell)

irm https://raw.githubusercontent.com/khalid-src/corv-client/main/install.ps1 | iex

With Go

go install github.com/khalid-src/corv-client/cmd/corv@latest

Update or remove

corv update      # download and install the latest release (checksum-verified)
corv uninstall   # remove corv; add --purge to also delete saved connections

corv update only runs when you run it - Corv never updates itself in the background.

Usage

Manage connections interactively:

The terminal interface supports keyboard and mouse navigation to add, edit, import from ~/.ssh/config, and connect. Connections can also be managed from the command line:

corv add srv-01 ubuntu@10.0.0.4                      # prompts for a password if needed
corv add srv-01 ubuntu@10.0.0.4 --key ~/.ssh/id_ed25519
corv add db-01 ubuntu@10.0.0.9 --jump ubuntu@bastion # reach through a bastion
corv import                                          # import hosts from ~/.ssh/config
corv list
corv rm srv-01

Hosts behind one or more bastions are reached with --jump (OpenSSH -J syntax: user@host1,user@host2). Jump hosts authenticate with ssh-agent or your keys; the target uses the connection's own credentials.

corv add reads any password without echo and stores it in the local encrypted vault; it is never passed as an argument.

Connect interactively:

Run a command non-interactively (the agent path):

corv srv-01 -- systemctl restart api
corv srv-01 --json -- df -h              # structured output for tools
corv srv-01 -- ./deploy.sh
echo 'cd /app && run "$X" | grep foo' | corv srv-01 --json --stdin
corv srv-01 --json --stdin < script.sh

A typical agent instruction such as "restart the API service on srv-01" requires only corv srv-01 -- systemctl restart api.

Command handling after -- is designed to do what you mean:

• a single argument is treated as a remote shell command line and run as-is, like ssh host "cmd" - e.g. corv srv -- "cd /app && make";
• multiple arguments are passed as a preserved argument vector, each shell-quoted so the remote cannot re-split them - e.g. corv srv -- sh -lc "cd /app && make".

This avoids the raw-ssh pitfall where quoted arguments lose their boundaries, which matters for agents that build argument vectors.

For complex shell text, nested quotes, or multi-line scripts, use an stdin mode. --stdin-base64 is the cross-shell-safe option because only ASCII base64 passes through the local pipe.

Windows / PowerShell

PowerShell can mangle quoting and pipe encoding, so encode a non-trivial remote command as UTF-8 base64 and send it with --stdin-base64:

$b64=[Convert]::ToBase64String([Text.Encoding]::UTF8.GetBytes(@'
set -eu
cd /srv/app && ./deploy.sh
'@)); $b64 | corv srv-01 --json --stdin-base64

Only ASCII base64 crosses the pipe, so the command arrives unchanged - quoting and any non-ASCII text survive intact. A simple exact argument vector can still use -- <command>.

Long commands are detached on the server automatically. If a command is still running after the broker's wait window, Corv returns the new bounded output, the run id, and exit code 75. Re-run the exact same command to watch the next delta; it attaches to the existing remote job and does not start a second copy. When the job finishes, Corv saves the log locally (up to 20 MiB; a larger log is truncated, with a marker and a truncated flag in corv output --json) and removes the remote temporary files:

corv srv-01 -- ./long-install.sh
corv srv-01 -- ./long-install.sh       # same command: continue watching
corv output <run-id>                   # finalize if done, then show the saved log

CORV_WAIT controls how long the broker waits before returning a running response. It accepts bare seconds (CORV_WAIT=30) or a Go duration (CORV_WAIT=500ms, CORV_WAIT=2m) and is read from the environment of each corv invocation, so it takes effect immediately without restarting the broker. corv output <run-id> checks an unfinished detached run and finalizes it automatically once the remote exit status exists. Remote temp files are cleaned on finalization; abandoned jobs are cleaned by the broker's startup sweep after 24 hours.

Remote command execution requires a POSIX shell and standard Unix command-line tools. Windows OpenSSH servers are not supported as remote execution targets.

Use with AI agents

Corv is built for AI coding agents (Claude, Codex, and others). Ready-to-use agent instructions live in integrations/:

• Claude / Claude Code - copy integrations/claude/corv-ssh into ~/.claude/skills/ (or a project's .claude/skills/).
• Codex - copy integrations/codex/AGENTS.md into your project.

The agent then runs commands by name and reads structured output:

corv <name> --json -- <command>

For non-trivial scripts or heavily quoted commands, agents should send the remote command as UTF-8 base64:

$b64=[Convert]::ToBase64String([Text.Encoding]::UTF8.GetBytes(@'
set -eu
cd /srv/app && ./deploy.sh
'@)); $b64 | corv <name> --json --stdin-base64

Agents should not run corv list --full or corv doctor --full unless the user explicitly asks; those modes show local connection details. Never put passwords, private keys, API tokens, kubeadm tokens, bearer tokens, or other secrets on the command line. Corv command history records command lines.

See integrations/README.md for details.

Connection reuse

A local broker process holds one authenticated SSH connection per machine. Each corv <name> -- <cmd> runs as a new channel over the held connection, so the connection and authentication cost is paid once rather than on every command. This behaviour is identical on Linux, macOS, and Windows.

The broker starts automatically on first use, exits after 15 minutes idle, and installs nothing on the server. It manages SSH connections only; it does not allocate a local pseudo-terminal, parse shell output, or maintain remote shell state. A held connection can be dropped explicitly:

Scope and limitations:

• This is connection reuse, not remote session persistence. Each command runs in its own shell with its own exit code; shell state such as the working directory does not carry between commands (combine them in a single command when required, e.g. cd /app && make).
• Because the broker is local, a held connection does not survive the local machine sleeping or a network interruption. Persistence across those events requires remote support, which Corv does not depend on by design.

Interactive sessions open a dedicated connection and proxy the remote pseudo-terminal to the local terminal, so no local pseudo-terminal is required on any platform.

Output processing

Corv normalises command output for programmatic consumers:

• progress bars and other carriage-return redraws are collapsed to their final state rather than reproduced as thousands of lines;
• ANSI control sequences, including colour, are removed;
• a command's stdout and stderr are captured together, interleaved in the order they were written, and returned in stdout; with --json, the stderr field carries Corv-level errors (e.g. transport failures), not the remote command's own stderr;
• a finished command returns its output in full up to a generous byte budget; only genuinely large output is trimmed to a leading and trailing section with a ... N line(s) hidden ... marker (the saved log, up to 20 MiB, stays available via corv output <run-id>), and a still-running command returns a short peek;
• transport failures are classified (auth_failed, unknown_host, unreachable, host_key, timeout, disconnected), and the remote exit code is propagated as the process exit code.

Security model

Corv runs entirely on the client and implements SSH through the maintained Go SSH library (golang.org/x/crypto/ssh).

• Nothing is installed on the destination server.
• Connection profiles are encrypted at rest with the OS-protected vault key, so the connection file does not expose hosts, users, or paths in plaintext (corv list is the way to view them).
• Passwords and key passphrases are stored in a local encrypted vault. The vault key is protected by DPAPI on Windows; on macOS and Linux Corv reads a provisioned Keychain / Secret Service key when present (it never auto-creates one) and otherwise uses a 0600 key file, the default. Stored secrets are read only by the local broker and sent over the authenticated SSH connection; they do not appear on a command line, in logs, or in command output. Key-based authentication or ssh-agent is recommended.
• Audit logs and saved run logs are local and can contain the command text or remote output an operator asked Corv to run. Never put passwords, private keys, API tokens, kubeadm tokens, bearer tokens, or other secrets on the command line; command history records command lines.
• Authentication is attempted in order: configured identity file, ssh-agent (via SSH_AUTH_SOCK on Unix, the openssh-ssh-agent named pipe on Windows), default ~/.ssh keys, then password.
• Bastion (ProxyJump) hops are host-key verified individually and can authenticate with ssh-agent, default keys, a per-hop identity file, or a password/passphrase sourced from a saved profile.
• Host keys are verified against ~/.ssh/known_hosts. An unknown host is rejected unless approved interactively; the broker never accepts unknown hosts automatically. A changed host key is always rejected.
• The broker uses OS-permissioned local IPC (Unix socket or Windows named pipe) plus an endpoint token for defense in depth.

Architecture

Corv is composed of small, independent modules so that the SSH backend or the output processor can be replaced without affecting the rest:

Development

make vet         # go vet ./...
make build       # build ./bin/corv
make build-all   # cross-compile linux/macOS/windows

Corv targets Go 1.25+ on Linux, macOS, and Windows.

License

See LICENSE.

Acknowledgments

Built with the assistance of AI coding tools: Claude Opus 4.8 and GPT-5.5.