agentjail installs a set of binaries plus a default policy bundle. The install script detects your platform and drops everything into place.
Platform note: the
agentjail installcommand (daemon + hook wiring) is macOS-only today. Claude Code is the only supported agent; Codex and Cursor support is not yet available.
Install
curl -fsSL https://agentjail.io/install.sh | sh
This downloads the release tarball for your platform (macOS arm64/amd64, Linux
arm64/amd64), verifies the SHA256 checksum, and installs the following binaries
to ~/.agentjail/bin/:
agentjail— the main CLIagentjail-hook— the tiny binary called by Claude Code’sPreToolUsehookagentjail-daemon— the persistent background daemon that keeps OPA warmagentjail-shieldandagentjail-netproxy— supporting binaries
Alternatively, if you use Homebrew:
brew install agentjail/tap/agentjail
Verify
agentjail --version
agentjail policy list
The first command confirms the binary is on your PATH; the second prints the
policies that are currently active.
Wire it into Claude Code
Run the install command to register the daemon and hook:
agentjail install --for claude-code
This starts the agentjail-daemon (via launchctl on macOS) and writes the
PreToolUse hook entry into ~/.claude/settings.json:
{
"hooks": {
"PreToolUse": [
{
"matcher": "*",
"hooks": [{ "type": "command", "command": "~/.agentjail/bin/agentjail-hook" }]
}
]
}
}
From this point on, every tool call Claude Code is about to make passes through
agentjail-hook, which forwards it to the daemon for policy evaluation in under
5 ms. Allowed calls run as normal; denied calls never reach the shell.