Local HTTP proxy run alongside Claude Code scrambles the TUI: BrokenPipe tracebacks printed to the shared terminal

Never write to stderr from proxy threads; log to a file and silence client hang-ups:

class Server(ThreadingHTTPServer):
    daemon_threads = True
    def handle_error(self, request, client_address):
        import sys, traceback
        exc = sys.exc_info()[1]
        if isinstance(exc, (BrokenPipeError, ConnectionResetError)):
            return
        with open(LOG_PATH, 'a') as f:
            traceback.print_exc(file=f)

class Handler(BaseHTTPRequestHandler):
    def log_message(self, *a): pass         # default logs to stderr too
    def finish(self):
        try: super().finish()
        except OSError: pass

Alternatively start the proxy with stdout/stderr redirected to a log file (>proxy.log 2>&1 &).