diff --git a/Resources/shell-integration/cmux-bash-integration.bash b/Resources/shell-integration/cmux-bash-integration.bash
index cbb3f103..ab4b6e2c 100644
--- a/Resources/shell-integration/cmux-bash-integration.bash
+++ b/Resources/shell-integration/cmux-bash-integration.bash
@@ -49,9 +49,6 @@ _CMUX_PR_POLL_PWD="${_CMUX_PR_POLL_PWD:-}"
 _CMUX_PR_POLL_INTERVAL="${_CMUX_PR_POLL_INTERVAL:-45}"
 _CMUX_PR_FORCE="${_CMUX_PR_FORCE:-0}"
 _CMUX_ASYNC_JOB_TIMEOUT="${_CMUX_ASYNC_JOB_TIMEOUT:-20}"
-_CMUX_PREEXEC_READY="${_CMUX_PREEXEC_READY:-0}"
-_CMUX_IN_PROMPT_COMMAND="${_CMUX_IN_PROMPT_COMMAND:-0}"
-_CMUX_DEBUG_TRAP_INSTALLED="${_CMUX_DEBUG_TRAP_INSTALLED:-0}"
 
 _CMUX_PORTS_LAST_RUN="${_CMUX_PORTS_LAST_RUN:-0}"
 _CMUX_TTY_NAME="${_CMUX_TTY_NAME:-}"
@@ -198,6 +195,27 @@ _cmux_report_pr_for_path() {
     _cmux_send "report_pr $number $url $status_opt --tab=$CMUX_TAB_ID --panel=$CMUX_PANEL_ID"
 }
 
+_cmux_child_pids() {
+    local parent_pid="$1"
+    [[ -n "$parent_pid" ]] || return 0
+    /bin/ps -ax -o pid= -o ppid= 2>/dev/null | /usr/bin/awk -v parent="$parent_pid" '$2 == parent { print $1 }'
+}
+
+_cmux_kill_process_tree() {
+    local pid="$1"
+    local signal="${2:-TERM}"
+    local child_pid=""
+    [[ -n "$pid" ]] || return 0
+
+    while IFS= read -r child_pid; do
+        [[ -n "$child_pid" ]] || continue
+        [[ "$child_pid" == "$pid" ]] && continue
+        _cmux_kill_process_tree "$child_pid" "$signal"
+    done < <(_cmux_child_pids "$pid")
+
+    kill "-$signal" "$pid" >/dev/null 2>&1 || true
+}
+
 _cmux_run_pr_probe_with_timeout() {
     local repo_path="$1"
     local probe_pid=""
@@ -213,10 +231,10 @@ _cmux_run_pr_probe_with_timeout() {
         sleep 1
         now=$SECONDS
         if (( _CMUX_ASYNC_JOB_TIMEOUT > 0 )) && (( now - started_at >= _CMUX_ASYNC_JOB_TIMEOUT )); then
-            kill "$probe_pid" >/dev/null 2>&1 || true
+            _cmux_kill_process_tree "$probe_pid" TERM
             sleep 0.2
             if kill -0 "$probe_pid" >/dev/null 2>&1; then
-                kill -9 "$probe_pid" >/dev/null 2>&1 || true
+                _cmux_kill_process_tree "$probe_pid" KILL
                 sleep 0.2
             fi
             if ! kill -0 "$probe_pid" >/dev/null 2>&1; then
@@ -231,7 +249,11 @@ _cmux_run_pr_probe_with_timeout() {
 
 _cmux_stop_pr_poll_loop() {
     if [[ -n "$_CMUX_PR_POLL_PID" ]]; then
-        kill "$_CMUX_PR_POLL_PID" >/dev/null 2>&1 || true
+        _cmux_kill_process_tree "$_CMUX_PR_POLL_PID" TERM
+        sleep 0.1
+        if kill -0 "$_CMUX_PR_POLL_PID" >/dev/null 2>&1; then
+            _cmux_kill_process_tree "$_CMUX_PR_POLL_PID" KILL
+        fi
         _CMUX_PR_POLL_PID=""
     fi
 }
@@ -269,38 +291,10 @@ _cmux_bash_cleanup() {
     _cmux_stop_pr_poll_loop
 }
 
-_cmux_preexec_trap() {
-    (( _CMUX_IN_PROMPT_COMMAND )) && return 0
-    (( _CMUX_PREEXEC_READY )) || return 0
-    _CMUX_PREEXEC_READY=0
-    _cmux_stop_pr_poll_loop
-
-    local cmd="${BASH_COMMAND## }"
-    case "$cmd" in
-        git\ *|git|gh\ *|gh|lazygit|lazygit\ *|tig|tig\ *|gitui|gitui\ *|stg\ *|jj\ *)
-            _CMUX_PR_FORCE=1
-            ;;
-    esac
-}
-
-_cmux_install_debug_trap() {
-    (( _CMUX_DEBUG_TRAP_INSTALLED )) && return 0
-
-    local existing
-    existing="$(trap -p DEBUG 2>/dev/null || true)"
-    if [[ -n "$existing" ]]; then
-        return 0
-    fi
-
-    trap '_cmux_preexec_trap' DEBUG
-    _CMUX_DEBUG_TRAP_INSTALLED=1
-}
-
 _cmux_prompt_command() {
     [[ -S "$CMUX_SOCKET_PATH" ]] || return 0
     [[ -n "$CMUX_TAB_ID" ]] || return 0
     [[ -n "$CMUX_PANEL_ID" ]] || return 0
-    _CMUX_IN_PROMPT_COMMAND=1
 
     local now=$SECONDS
     local pwd="$PWD"
@@ -416,9 +410,6 @@ _cmux_prompt_command() {
     if (( now - _CMUX_PORTS_LAST_RUN >= 10 )); then
         _cmux_ports_kick
     fi
-
-    _CMUX_IN_PROMPT_COMMAND=0
-    _CMUX_PREEXEC_READY=1
 }
 
 _cmux_install_prompt_command() {
@@ -471,4 +462,3 @@ _cmux_fix_path
 unset -f _cmux_fix_path
 
 _cmux_install_prompt_command
-_cmux_install_debug_trap
diff --git a/Resources/shell-integration/cmux-zsh-integration.zsh b/Resources/shell-integration/cmux-zsh-integration.zsh
index b6b82c88..821f3d19 100644
--- a/Resources/shell-integration/cmux-zsh-integration.zsh
+++ b/Resources/shell-integration/cmux-zsh-integration.zsh
@@ -220,6 +220,27 @@ _cmux_report_pr_for_path() {
     _cmux_send "report_pr $number $url $status_opt --tab=$CMUX_TAB_ID --panel=$CMUX_PANEL_ID"
 }
 
+_cmux_child_pids() {
+    local parent_pid="$1"
+    [[ -n "$parent_pid" ]] || return 0
+    /bin/ps -ax -o pid= -o ppid= 2>/dev/null | /usr/bin/awk -v parent="$parent_pid" '$2 == parent { print $1 }'
+}
+
+_cmux_kill_process_tree() {
+    local pid="$1"
+    local signal="${2:-TERM}"
+    local child_pid=""
+    [[ -n "$pid" ]] || return 0
+
+    while IFS= read -r child_pid; do
+        [[ -n "$child_pid" ]] || continue
+        [[ "$child_pid" == "$pid" ]] && continue
+        _cmux_kill_process_tree "$child_pid" "$signal"
+    done < <(_cmux_child_pids "$pid")
+
+    kill "-$signal" "$pid" >/dev/null 2>&1 || true
+}
+
 _cmux_run_pr_probe_with_timeout() {
     local repo_path="$1"
     local probe_pid=""
@@ -235,10 +256,10 @@ _cmux_run_pr_probe_with_timeout() {
         sleep 1
         now=$EPOCHSECONDS
         if (( _CMUX_ASYNC_JOB_TIMEOUT > 0 )) && (( now - started_at >= _CMUX_ASYNC_JOB_TIMEOUT )); then
-            kill "$probe_pid" >/dev/null 2>&1 || true
+            _cmux_kill_process_tree "$probe_pid" TERM
             sleep 0.2
             if kill -0 "$probe_pid" >/dev/null 2>&1; then
-                kill -9 "$probe_pid" >/dev/null 2>&1 || true
+                _cmux_kill_process_tree "$probe_pid" KILL
                 sleep 0.2
             fi
             if ! kill -0 "$probe_pid" >/dev/null 2>&1; then
@@ -253,7 +274,11 @@ _cmux_run_pr_probe_with_timeout() {
 
 _cmux_stop_pr_poll_loop() {
     if [[ -n "$_CMUX_PR_POLL_PID" ]]; then
-        kill "$_CMUX_PR_POLL_PID" >/dev/null 2>&1 || true
+        _cmux_kill_process_tree "$_CMUX_PR_POLL_PID" TERM
+        sleep 0.1
+        if kill -0 "$_CMUX_PR_POLL_PID" >/dev/null 2>&1; then
+            _cmux_kill_process_tree "$_CMUX_PR_POLL_PID" KILL
+        fi
         _CMUX_PR_POLL_PID=""
     fi
 }
diff --git a/tests/test_issue_1138_sidebar_pr_polling.py b/tests/test_issue_1138_sidebar_pr_polling.py
index 92f48b24..973e98dd 100644
--- a/tests/test_issue_1138_sidebar_pr_polling.py
+++ b/tests/test_issue_1138_sidebar_pr_polling.py
@@ -8,6 +8,8 @@ Validates that shell integration:
    branch-name matching
 3) clears stale PR state when the branch changes and the new probe fails
 4) recovers when a gh probe wedges longer than the async timeout
+5) keeps polling in bash after prompt-render helper commands run
+6) tears down the timed-out gh probe instead of leaking it in the background
 """
 
 from __future__ import annotations
@@ -91,6 +93,7 @@ def _gh_stub() -> str:
         #!/bin/sh
         args_log="${CMUX_TEST_GH_ARGS_LOG:?}"
         count_file="${CMUX_TEST_GH_COUNT_FILE:?}"
+        pid_file="${CMUX_TEST_GH_PID_FILE:-}"
         scenario="${CMUX_TEST_SCENARIO:?}"
         head_file="${CMUX_TEST_HEAD_FILE:?}"
 
@@ -119,6 +122,9 @@ def _gh_stub() -> str:
         fi
 
         case "$scenario" in
+          prompt_helper_idle)
+            printf '1138\\tOPEN\\thttps://github.com/manaflow-ai/cmux/pull/1138\\n'
+            ;;
           transient_same_context)
             if [ "$count" -eq 1 ]; then
               printf 'rate limit exceeded\\n' >&2
@@ -140,6 +146,9 @@ def _gh_stub() -> str:
             ;;
           timeout_recovery)
             if [ "$count" -eq 1 ]; then
+              if [ -n "$pid_file" ]; then
+                printf '%s\\n' "$$" > "$pid_file"
+              fi
               sleep "${CMUX_TEST_HANG_SECONDS:-4}"
               exit 0
             fi
@@ -156,6 +165,14 @@ def _gh_stub() -> str:
 
 def _shell_command(kind: str, scenario: str) -> str:
     shared = {
+        "prompt_helper_idle": (
+            'cd "$CMUX_TEST_REPO"\n'
+            '_CMUX_PR_POLL_INTERVAL=1\n'
+            '_cmux_prompt_entry\n'
+            ': "$(/bin/printf helper)"\n'
+            'sleep 3\n'
+            '_cmux_cleanup\n'
+        ),
         "transient_same_context": (
             'cd "$CMUX_TEST_REPO"\n'
             '_CMUX_PR_POLL_INTERVAL=1\n'
@@ -197,7 +214,6 @@ def _shell_command(kind: str, scenario: str) -> str:
         return textwrap.dedent(
             f"""\
             source "$CMUX_TEST_SCRIPT"
-            trap - DEBUG
             _cmux_send() {{ printf '%s\\n' "$1" >> "$CMUX_TEST_SEND_LOG"; }}
             _cmux_prompt_entry() {{ _cmux_prompt_command; }}
             _cmux_cleanup() {{ type _cmux_bash_cleanup >/dev/null 2>&1 && _cmux_bash_cleanup; }}
@@ -221,6 +237,16 @@ def _report_line(number: int) -> str:
     )
 
 
+def _pid_exists(pid: int) -> bool:
+    try:
+        os.kill(pid, 0)
+    except ProcessLookupError:
+        return False
+    except PermissionError:
+        return True
+    return True
+
+
 def _run_case(base: Path, *, shell: str, shell_args: list[str], script: Path, scenario: str) -> tuple[int, str]:
     bindir = base / "bin"
     repo = base / "repo"
@@ -229,6 +255,7 @@ def _run_case(base: Path, *, shell: str, shell_args: list[str], script: Path, sc
     send_log = base / f"{shell}-{scenario}-send.log"
     gh_count_file = base / f"{shell}-{scenario}-gh-count.txt"
     gh_args_log = base / f"{shell}-{scenario}-gh-args.log"
+    gh_pid_file = base / f"{shell}-{scenario}-gh-pid.txt"
     head_file = repo_git / "HEAD"
 
     bindir.mkdir(parents=True, exist_ok=True)
@@ -248,6 +275,7 @@ def _run_case(base: Path, *, shell: str, shell_args: list[str], script: Path, sc
     env["CMUX_TEST_SEND_LOG"] = str(send_log)
     env["CMUX_TEST_GH_COUNT_FILE"] = str(gh_count_file)
     env["CMUX_TEST_GH_ARGS_LOG"] = str(gh_args_log)
+    env["CMUX_TEST_GH_PID_FILE"] = str(gh_pid_file)
     env["CMUX_TEST_SCENARIO"] = scenario
     env["CMUX_TEST_HEAD_FILE"] = str(head_file)
     env["CMUX_TEST_HANG_SECONDS"] = "4"
@@ -274,6 +302,13 @@ def _run_case(base: Path, *, shell: str, shell_args: list[str], script: Path, sc
     if any(not line.startswith("pr view ") for line in gh_args_lines):
         return (1, f"{shell}/{scenario}: expected gh pr view only\n" + "\n".join(gh_args_lines))
 
+    if scenario == "prompt_helper_idle":
+        if gh_count < 2:
+            return (1, f"{shell}/{scenario}: expected idle polling to survive prompt helpers, saw {gh_count}")
+        if _report_line(1138) not in send_lines:
+            return (1, f"{shell}/{scenario}: missing report_pr payload\n" + "\n".join(send_lines))
+        return (0, f"{shell}/{scenario}: ok")
+
     if scenario == "transient_same_context":
         if gh_count < 2:
             return (1, f"{shell}/{scenario}: expected at least 2 gh probes while idle, saw {gh_count}")
@@ -303,6 +338,10 @@ def _run_case(base: Path, *, shell: str, shell_args: list[str], script: Path, sc
             return (1, f"{shell}/{scenario}: expected timed-out probe to be retried, saw {gh_count}")
         if _report_line(1138) not in send_lines:
             return (1, f"{shell}/{scenario}: missing report_pr after timeout recovery\n" + "\n".join(send_lines))
+        if gh_pid_file.exists():
+            gh_pid = int(gh_pid_file.read_text(encoding="utf-8").strip() or "0")
+            if gh_pid > 0 and _pid_exists(gh_pid):
+                return (1, f"{shell}/{scenario}: timed-out gh probe still running as pid {gh_pid}")
         return (0, f"{shell}/{scenario}: ok")
 
     return (1, f"{shell}/{scenario}: unhandled scenario")
@@ -315,6 +354,7 @@ def main() -> int:
         ("bash", ["--noprofile", "--norc", "-c"], root / "Resources" / "shell-integration" / "cmux-bash-integration.bash"),
     ]
     scenarios = [
+        "prompt_helper_idle",
         "transient_same_context",
         "branch_switch_clear",
         "timeout_recovery",