diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4dc8d44511..056759665a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -41,6 +41,7 @@
 - [Fix][issue3601]: `CmdSet.add(..., allow_duplicates=True)` didn't allow duplicate cmd keys (Griatch)
 - [Fix][issue3194]: Make filtering on AttributeProperties consistent across typeclasses (Griatch)
 - [Fix][issue2774]: Properly support `\n` in `evennia connections` long descriptions (Griatch)
+- [Fix][issue3312]: Handle all edge cases breaking `monitor/monitored` `input_funcs` (Griatch)
 - [Doc][pull3801]: Move Evennia doc build system to latest Sphinx/myST
   (PowershellNinja, also honorary mention to electroglyph)
 - [Doc][pull3800]: Describe support for Telnet SSH in HAProxy documentation (holl0wstar)
@@ -75,6 +76,7 @@
 [issue3601]: https://github.com/evennia/evennia/issues/3601
 [issue3194]: https://github.com/evennia/evennia/issues/3194
 [issue2774]: https://github.com/evennia/evennia/issues/2774
+[issue3312]: https://github.com/evennia/evennia/issues/3312
 
 
 ## Evennia 5.0.1
diff --git a/evennia/server/inputfuncs.py b/evennia/server/inputfuncs.py
index 0c56d20ea8..79b240d30f 100644
--- a/evennia/server/inputfuncs.py
+++ b/evennia/server/inputfuncs.py
@@ -499,9 +499,20 @@ def monitored(session, *args, **kwargs):
 
     """
     from evennia.scripts.monitorhandler import MONITOR_HANDLER
+    import pickle
+
+    def _safe_pickle(value):
+        try:
+            pickle.dumps(value, pickle.HIGHEST_PROTOCOL)
+            return value
+        except Exception:
+            return str(value)
 
     obj = session.puppet
-    monitors = MONITOR_HANDLER.all(obj=obj)
+    monitors = []
+    for mon_obj, fieldname, idstring, persistent, monitor_kwargs in MONITOR_HANDLER.all(obj=obj):
+        safe_kwargs = {key: _safe_pickle(val) for key, val in monitor_kwargs.items()}
+        monitors.append((_safe_pickle(mon_obj), fieldname, idstring, persistent, safe_kwargs))
     session.msg(monitored=(monitors, {}))
 
 
diff --git a/evennia/server/tests/test_inputfuncs.py b/evennia/server/tests/test_inputfuncs.py
new file mode 100644
index 0000000000..58f9b24be9
--- /dev/null
+++ b/evennia/server/tests/test_inputfuncs.py
@@ -0,0 +1,34 @@
+"""
+Tests for server input functions.
+"""
+
+import pickle
+
+import evennia
+from evennia.server import inputfuncs
+from evennia.utils.test_resources import BaseEvenniaTest
+
+
+class TestMonitoredInputfunc(BaseEvenniaTest):
+    """
+    Regressions for monitor/monitored inputfunc handling.
+    """
+
+    def test_monitored_payload_is_pickleable(self):
+        """
+        The monitored payload sent over AMP must not include raw Session objects.
+        """
+
+        self.session.puppet = self.char1
+        inputfuncs.monitor(self.session, name="location")
+        inputfuncs.monitored(self.session)
+
+        sent_session = evennia.SESSION_HANDLER.data_out.call_args.args[0]
+        sent_kwargs = evennia.SESSION_HANDLER.data_out.call_args.kwargs
+        monitors = sent_kwargs["monitored"][0]
+        monitor_kwargs = monitors[0][4]
+
+        self.assertEqual(sent_session, self.session)
+        self.assertIn("session", monitor_kwargs)
+        self.assertIsInstance(monitor_kwargs["session"], str)
+        pickle.dumps((self.session.sessid, sent_kwargs), pickle.HIGHEST_PROTOCOL)