diff --git a/agent-queue/agent-queue.sh b/agent-queue/agent-queue.sh
index e1dcd18..f475575 100755
--- a/agent-queue/agent-queue.sh
+++ b/agent-queue/agent-queue.sh
@@ -112,6 +112,21 @@ _mtime() {
   stat -f %m "$1" 2>/dev/null || stat -c %Y "$1" 2>/dev/null || echo ""
 }
 
+# _pidstart <pid> -> the process start time as reported by ps (whitespace-normalized).
+# Used as an identity token so a recycled pid is never mistaken for our worker.
+_pidstart() { ps -o lstart= -p "$1" 2>/dev/null | awk '{$1=$1;print}'; }
+
+# _pid_alive <pid> <pidstart> -> 0 if the pid is live AND (when a start time was
+# recorded) its current start time still matches — defeating pid reuse.
+_pid_alive() {
+  local pid=$1 want=$2 cur
+  [[ -n "$pid" ]] || return 1
+  kill -0 "$pid" 2>/dev/null || return 1
+  [[ -z "$want" ]] && return 0
+  cur=$(_pidstart "$pid")
+  [[ "$cur" == "$want" ]]
+}
+
 # _dur_to_secs <dur> -> seconds. Accepts 90, 90s, 45m, 2h, 1d. Invalid/empty -> 0.
 _dur_to_secs() {
   local d=$1
@@ -139,7 +154,8 @@ _meta_active() {
   grep -q '^ended=' "$f" && return 1
   pid=$(grep '^pid=' "$f" | head -1 | cut -d= -f2)
   if [[ -n "$pid" ]]; then
-    kill -0 "$pid" 2>/dev/null
+    local pidstart; pidstart=$(grep '^pidstart=' "$f" | head -1 | cut -d= -f2-)
+    _pid_alive "$pid" "$pidstart"
     return $?
   fi
   mt=$(_mtime "$f"); age=$(( $(date +%s) - ${mt:-0} ))
@@ -386,7 +402,7 @@ cmd_run() {
         echo "started=$(date +%s)"
       } > "$STATE/$job.meta"
       run_worker "$doing_file" &
-      echo "pid=$!" >> "$STATE/$job.meta"
+      { echo "pid=$!"; echo "pidstart=$(_pidstart "$!")"; } >> "$STATE/$job.meta"
       log "▶ launching $C_BOLD$job$C_RESET (engine=$w_eng, lock=$w_key)"
       sleep 1
       running=$(active_workers)
@@ -420,8 +436,8 @@ cmd_status() {
   for f in "$STATE"/*.meta; do
     [[ -e "$f" ]] || continue
     grep -q '^ended=' "$f" && continue
-    local pid; pid=$(grep '^pid=' "$f" | cut -d= -f2)
-    [[ -n "$pid" ]] && kill -0 "$pid" 2>/dev/null || continue
+    local pid pidstart; pid=$(grep '^pid=' "$f" | cut -d= -f2); pidstart=$(grep '^pidstart=' "$f" | cut -d= -f2-)
+    _pid_alive "$pid" "$pidstart" || continue
     if ! $printed; then printf '  %sRUNNING%s\n' "$C_BOLD" "$C_RESET"; printed=true; fi
     local job eng start now el last lmt age stall=""
     job=$(grep '^job=' "$f" | cut -d= -f2)
@@ -450,12 +466,12 @@ cmd_dash() {
 
 cmd_stop() {
   ensure_dirs
-  local killed=0 f pid
+  local killed=0 f pid pidstart
   for f in "$STATE"/*.meta; do
     [[ -e "$f" ]] || continue
     grep -q '^ended=' "$f" && continue
-    pid=$(grep '^pid=' "$f" | cut -d= -f2)
-    [[ -n "$pid" ]] && kill -0 "$pid" 2>/dev/null && { kill "$pid" 2>/dev/null && killed=$((killed+1)); }
+    pid=$(grep '^pid=' "$f" | cut -d= -f2); pidstart=$(grep '^pidstart=' "$f" | cut -d= -f2-)
+    _pid_alive "$pid" "$pidstart" && { kill "$pid" 2>/dev/null && killed=$((killed+1)); }
   done
   [[ -f "$STATE/daemon.pid" ]] && kill "$(cat "$STATE/daemon.pid")" 2>/dev/null
   rm -f "$STATE/daemon.pid"