Reconnect should preserve state
Disconnect the client mid-run, switch networks, reconnect from the phone, and verify the same prompt, cwd, pending approval, and output stream are still there.
PTY and phone reconnect
Keeping the terminal alive is not the same as keeping the host alive.
A PTY daemon, phone client, or reconnect tool can preserve the Claude Code session. It still needs a dev box that stays awake, reachable, cool, and restorable.
Sleep should be tested separately
Run a heartbeat outside Claude Code, then test lock, sleep/wake, lid close, Wi-Fi change, and reboot. Missing timestamps mean the host failed, not the PTY.
Awake mode needs an off switch
If the dev box is a notebook, temporary awake mode should end with battery, heat, reachability, and restored sleep settings in the receipt.
Host heartbeat
Keep proof outside the PTY.
This catches the difference between a preserved session and a sleeping dev box.
while true; do date >> ~/pty-host-survival.log; sleep 30; done
Copy prompt
Ask the agent to split the layers.
Use this before trusting a PTY wrapper, phone terminal, or reconnect tool for unattended work.
Test this Claude Code PTY/reconnect setup in two layers. First verify PTY survival: disconnect, reconnect, switch networks, and confirm prompt, cwd, pending approval, and output state are preserved. Then verify host survival separately: heartbeat file outside Claude, sleep/wake, lid close if relevant, Wi-Fi change, battery, heat, and restore. Stop if the host sleeps, network dies, battery/heat is unsafe, or normal sleep settings cannot be restored.
Want Codex to handle the local host layer?
Take A Coffee gives Codex a temporary awake mode, host checks, restore step, and receipt for macOS and Windows notebook runs.