Summary
Fixes X11/XCB crash when running serena-mcp-server in directories without source files
Adds headless environment detection to prevent GUI operations in SSH/WSL/Docker environments
Improves error messages to provide clear guidance when no source files are found
Problem
When running serena-mcp-server --context ide-assistant --project /empty/dir in a headless environment (SSH, WSL, Docker), the application would crash with X11/XCB errors:
[xcb] Unknown sequence number while appending request
[xcb] You called XInitThreads, this is not your fault
[xcb] Aborting, sorry about that.
python: ../../src/xcb_io.c:157: append_pending_request: Assertion `\!xcb_xlib_unknown_seq_number' failed.
Root Cause
Empty directories cause ProjectConfig.autogenerate() to raise a ValueError
The exception handler attempts to show a GUI error dialog using tkinter
In headless environments, tkinter crashes with X11/XCB errors
Solution
Headless Detection: Added is_headless_environment() to detect when running without a display
Skip GUI in Headless: Modified show_fatal_exception_safe() to skip GUI attempts in headless environments
Better Error Messages: Improved the error message for empty projects with clear instructions
Joshua Shanks