warp-notify.sh fails silently when /dev/tty is unavailable in Claude Code sandbox

[thebrownproject]

Summary

warp-notify.sh writes OSC 777 escape sequences to /dev/tty, but Claude Code runs hook scripts in a sandboxed subshell where /dev/tty is not attached ("Device not configured"). The || true on line 21 swallows the error, so all notifications silently fail.

Environment

• macOS (Darwin 25.3.0)
• Warp v0.2026.05.18.05.32.stable_02
• Claude Code 2.1.142
• Plugin warp@claude-code-warp v2.0.0
• WARP_CLI_AGENT_PROTOCOL_VERSION=1
• TERM_PROGRAM=WarpTerminal

Steps to reproduce

1. Launch Claude Code in a Warp terminal tab
2. Trigger any notification (idle prompt, permission request, stop)
3. No in-app notification chip appears

Root cause

Inside Claude Code's hook execution environment:

$ tty
not a tty

$ printf '' > /dev/tty
/dev/tty: Device not configured

The parent claude process does have a TTY (e.g. ttys018), but the subshell spawned for hook scripts does not inherit it.

Workaround

Replace the /dev/tty write in warp-notify.sh with a function that walks up the process tree to find the ancestor's TTY device:

resolve_tty() {
    if printf '' 2>/dev/null > /dev/tty 2>/dev/null; then
        echo /dev/tty
        return
    fi
    local pid=$$
    while [ "$pid" -gt 1 ] 2>/dev/null; do
        local ancestor_tty
        ancestor_tty=$(ps -o tty= -p "$pid" 2>/dev/null | tr -d ' ')
        if [ -n "$ancestor_tty" ] && [ "$ancestor_tty" != "??" ]; then
            local dev="/dev/$ancestor_tty"
            if [ -w "$dev" ]; then
                echo "$dev"
                return
            fi
        fi
        pid=$(ps -o ppid= -p "$pid" 2>/dev/null | tr -d ' ')
    done
    return 1
}

TTY_DEV=$(resolve_tty) || exit 0
printf '\033]777;notify;%s;%s\007' "$TITLE" "$BODY" > "$TTY_DEV" 2>/dev/null || true

This resolves the issue and notifications work correctly after the patch.

[thebrownproject]

Closing as duplicate — this is the same /dev/tty issue reported in #54, #53, #49, #47, #43, #38, #36. Looks like v2.1.0 addresses it by switching to stdout JSON output instead of writing OSC sequences to /dev/tty directly.