What is zcode-keysmith?

zcode-keysmith is a small Python installer that patches how the desktop app ZCode starts its background agent process on macOS. Instead of changing the ZCode app itself, it points ZCode at a wrapper script that loads a cached copy of ZCode's own runtime, then swaps in a custom system prompt file before that runtime launches. The end result is that a Markdown file you control gets injected as the system message every time ZCode starts a new agent session, without modifying the original app bundle. The tool works by reading two environment variables that ZCode already checks when it starts its agent-server process, and redirecting one of them to a wrapper script installed under a hidden folder in your home directory. That wrapper reads ZCode's bundled runtime file, caches a modified copy that points to your custom system-role file, and then launches that cached copy using ZCode's own Electron process, preferring the internal Helper executable so the background process does not show up as a second ZCode icon in the Dock. Installation is done from the command line with a dry run step first, so you can see exactly which files will be written before confirming. Files land under a .zcode-keysmith folder in your home directory, plus a macOS LaunchAgent so the same environment variables persist across logins. The installer explicitly states it does not read, store, or print any API keys, tokens, or provider settings, all of which stay managed by ZCode itself. After installing, you quit and reopen ZCode, start a new task, and run a verify command that checks whether the wrapper was actually invoked. The README also documents a doctor command for checking installation status, an uninstall command that backs up and removes the managed files, and a logging file that records each wrapper start with a timestamp and process ID but no secrets. The project is part of a small family of similar keysmith tools the same author built for other AI coding tools like Codex CLI and Claude Code. It is written in Python 3.10 or later and released under the MIT license.