diff --git a/bin/dm.py b/bin/dm.py
index d6193c8..66f5a64 100755
--- a/bin/dm.py
+++ b/bin/dm.py
@@ -27,6 +27,7 @@ Usage:
   dm.py thread --from opm --to 646 --target main "message"
 """
 import argparse
+import os
 import re
 import subprocess
 import time
@@ -47,8 +48,12 @@ def log_event(event):
     with open(LOG_FILE, "a") as f:
         f.write(json.dumps(event) + "\n")
 
-def run(cmd, timeout=60):
-    result = subprocess.run(cmd, shell=True, capture_output=True, text=True, timeout=timeout)
+def run(cmd, timeout=60, priority=None):
+    # priority: CDP queue priority for the subprocess (high/normal/low).
+    # DM sends are user-facing -> high. Reads stay at default (normal).
+    env = dict(os.environ, CDP_PRIORITY=priority) if priority else None
+    result = subprocess.run(cmd, shell=True, capture_output=True, text=True,
+                            timeout=timeout, env=env)
     return result.stdout.strip()
 
 def run_full(cmd, timeout=60):
@@ -105,7 +110,8 @@ def dm_send(agent, target, message, verify=True, raw=False, to_agent=None):
     max_retries = 3
     delivered = False
     for attempt in range(max_retries):
-        run(f'{NETVM_EXEC} {recipient} -- python3 {API} --account {recipient} send "{safe}"')
+        run(f'{NETVM_EXEC} {recipient} -- python3 {API} --account {recipient} send "{safe}"',
+            priority="high")
         time.sleep(3)  # Wait for message to propagate
 
         # Verify by reading recipient's chat (independent check, not local echo)
diff --git a/bin/muse-chat-api.py b/bin/muse-chat-api.py
index 9cb0947..750b7c9 100755
--- a/bin/muse-chat-api.py
+++ b/bin/muse-chat-api.py
@@ -25,6 +25,11 @@ try:
     HAS_SIDECHAT_MANAGER = True
 except ImportError:
     HAS_SIDECHAT_MANAGER = False
+try:
+    from cdp_queue import cdp_slot, PRIORITY_HIGH, PRIORITY_NORMAL, PRIORITY_LOW
+    HAS_CDP_QUEUE = True
+except ImportError:
+    HAS_CDP_QUEUE = False
 
 
 def _load_accounts():
@@ -493,52 +498,65 @@ def main():
 
     node, cdp_url = ACCOUNTS[args.account]
     page = get_page(node, cdp_url)
-    ws = websocket.create_connection(page['webSocketDebuggerUrl'], timeout=15)
 
-    try:
-        if args.command == 'send':
-            if not args.arg:
-                print("ERROR: send requires a message", file=sys.stderr)
-                sys.exit(1)
-            cmd_send(ws, " ".join(args.arg))
-        elif args.command == 'messages':
-            n = int(args.arg[0]) if args.arg else 5
-            w = int(args.arg[1]) if len(args.arg) > 1 else 200
-            cmd_messages(ws, n, w)
-        elif args.command == 'wait':
-            t = int(args.arg[0]) if args.arg else 30
-            cmd_wait(ws, t)
-        elif args.command == 'approvals':
-            cmd_approvals(ws)
-        elif args.command == 'sidechat':
-            if not args.arg:
-                print("ERROR: sidechat requires subcommand (use|main|list|create)", file=sys.stderr)
-                sys.exit(1)
-            sub = args.arg[0]
-            if sub == "create":
-                cmd_sidechat_create(ws)
-            elif sub == "use":
-                if len(args.arg) < 2:
-                    print("ERROR: sidechat use requires chat_id", file=sys.stderr)
+    # CDP operation queue: serialize browser access across processes.
+    # Priority from CDP_PRIORITY env (high/normal/low); default normal.
+    # Falls back to unqueued if cdp_queue is unavailable.
+    import contextlib
+    if HAS_CDP_QUEUE:
+        _prio_name = os.environ.get("CDP_PRIORITY", "normal").lower()
+        _prio = {"high": PRIORITY_HIGH, "low": PRIORITY_LOW}.get(
+            _prio_name, PRIORITY_NORMAL)
+        _slot = cdp_slot(node, priority=_prio)
+    else:
+        _slot = contextlib.nullcontext()
+    with _slot:
+        ws = websocket.create_connection(page['webSocketDebuggerUrl'], timeout=15)
+
+        try:
+            if args.command == 'send':
+                if not args.arg:
+                    print("ERROR: send requires a message", file=sys.stderr)
                     sys.exit(1)
-                cmd_sidechat_use(ws, args.arg[1])
-            elif sub == "main":
-                cmd_sidechat_main(ws)
-            elif sub == "list":
-                cmd_sidechat_list(ws)
-            else:
-                print(f"ERROR: unknown sidechat subcommand: {sub}", file=sys.stderr)
-                sys.exit(1)
-        elif args.command == 'url':
-            cmd_url(ws)
-        elif args.command == 'upload':
-            if not args.arg:
-                print("ERROR: upload requires a filepath", file=sys.stderr)
-                sys.exit(1)
-            cmd_upload(ws, args.arg[0], message=args.message,
-                       dry_run=args.dry_run)
-    finally:
-        ws.close()
+                cmd_send(ws, " ".join(args.arg))
+            elif args.command == 'messages':
+                n = int(args.arg[0]) if args.arg else 5
+                w = int(args.arg[1]) if len(args.arg) > 1 else 200
+                cmd_messages(ws, n, w)
+            elif args.command == 'wait':
+                t = int(args.arg[0]) if args.arg else 30
+                cmd_wait(ws, t)
+            elif args.command == 'approvals':
+                cmd_approvals(ws)
+            elif args.command == 'sidechat':
+                if not args.arg:
+                    print("ERROR: sidechat requires subcommand (use|main|list|create)", file=sys.stderr)
+                    sys.exit(1)
+                sub = args.arg[0]
+                if sub == "create":
+                    cmd_sidechat_create(ws)
+                elif sub == "use":
+                    if len(args.arg) < 2:
+                        print("ERROR: sidechat use requires chat_id", file=sys.stderr)
+                        sys.exit(1)
+                    cmd_sidechat_use(ws, args.arg[1])
+                elif sub == "main":
+                    cmd_sidechat_main(ws)
+                elif sub == "list":
+                    cmd_sidechat_list(ws)
+                else:
+                    print(f"ERROR: unknown sidechat subcommand: {sub}", file=sys.stderr)
+                    sys.exit(1)
+            elif args.command == 'url':
+                cmd_url(ws)
+            elif args.command == 'upload':
+                if not args.arg:
+                    print("ERROR: upload requires a filepath", file=sys.stderr)
+                    sys.exit(1)
+                cmd_upload(ws, args.arg[0], message=args.message,
+                           dry_run=args.dry_run)
+        finally:
+            ws.close()
 
 if __name__ == '__main__':
     main()