A bare `bh` invocation blocks forever on sys.stdin.read(). Detect a TTY
stdin and exit with a one-line usage hint instead, so the failure mode
is obvious.
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Connection management (addresses "shit ton of daemons" problem):
- Socket is the lock. Daemon refuses to start if another is already
listening (5-line check).
- PID file at /tmp/harnesless.pid written on start, removed on exit.
- ensure_daemon() / kill_daemon() / daemon_alive() helpers.
- run.py auto-calls ensure_daemon() before exec — users never manage
the daemon manually.
- kill_daemon uses PID file (robust) instead of pkill pattern matching
(was silently missing because the process command line didn't contain
the "harnesless/" prefix).
Post-task ritual added to SKILL.md: after every browser task, extract
ONE generalizable friction point and make the simplest possible
improvement (2-line helper, one-line gotcha, recipe correction).
This is how the harness sharpens itself over time.
Verified end-to-end: kill_daemon → 0 processes + files cleaned → next
run.py → auto-starts exactly one daemon. Second `uv run daemon.py`
exits with "daemon already running" message instead of racing.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Three-process architecture: daemon.py holds one persistent CDP WebSocket
to the user's running Chrome (via chrome://inspect), short-lived run.py
processes talk to it over a Unix socket, helpers.py is the transparent
layer the LLM reads and edits at will.
Philosophy: no CLI, no fixed API surface. The LLM writes Python blocks
against ~13 tiny helpers (cdp, click, type_text, screenshot, get_dom,
etc.) and edits helpers.py on the fly when a pattern repeats. Coordinate
clicks default because they pass through iframes/shadow DOM/cross-origin
at the compositor level.
Uses cdp-use internally for send_raw only (ignores its 36k lines of
typed wrappers — raw CDP strings tokenize better than typed calls).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Magnus Müller