diff --git a/features/memory_service_clock_wait.feature b/features/memory_service_clock_wait.feature
new file mode 100644
index 000000000..85b0883ab
--- /dev/null
+++ b/features/memory_service_clock_wait.feature
@@ -0,0 +1,6 @@
+Feature: Memory service timestamp guards
+
+  Scenario: Wait helper enforces deadline when clock freezes
+    Given the memory service coverage steps module
+    When I wait for clock advancement with a frozen clock and deadline 0.01 seconds
+    Then the wait helper raises a deadline assertion
diff --git a/features/steps/memory_service_clock_wait_steps.py b/features/steps/memory_service_clock_wait_steps.py
new file mode 100644
index 000000000..f611c2170
--- /dev/null
+++ b/features/steps/memory_service_clock_wait_steps.py
@@ -0,0 +1,62 @@
+"""Behave steps validating timestamp wait helper for memory service coverage."""
+
+from __future__ import annotations
+
+import importlib
+from datetime import UTC, datetime
+from typing import Any
+
+from behave import given, then, when
+
+
+@given("the memory service coverage steps module")
+def step_get_memory_service_module(context: Any) -> None:
+    """Import the coverage steps module and ensure wait helper exists."""
+
+    module = importlib.import_module("features.steps.memory_service_coverage_steps")
+    context.memory_service_steps_module = module
+    assert hasattr(
+        module, "_wait_for_clock_advance"
+    ), "memory_service_coverage_steps._wait_for_clock_advance is required"
+
+
+@when(
+    "I wait for clock advancement with a frozen clock and deadline {deadline:f} seconds"
+)
+def step_wait_with_frozen_clock(context: Any, deadline: float) -> None:
+    """Execute the wait helper with a clock that never advances."""
+
+    module = context.memory_service_steps_module
+    before = datetime.now(UTC)
+    context._wait_deadline = deadline
+    context._captured_error = None
+    context._original_datetime = module.datetime
+
+    class FrozenDateTime:
+        """Stub datetime that always returns the same moment."""
+
+        UTC = module.UTC
+
+        def __init__(self, value: datetime) -> None:
+            self._value = value
+
+        def now(self, tz: object) -> datetime:
+            return self._value
+
+    module.datetime = FrozenDateTime(before)
+
+    try:
+        module._wait_for_clock_advance(before, deadline_secs=deadline)
+    except AssertionError as err:
+        context._captured_error = err
+    finally:
+        module.datetime = context._original_datetime
+
+
+@then("the wait helper raises a deadline assertion")
+def step_expect_deadline_assertion(context: Any) -> None:
+    """Validate the helper raised AssertionError with deadline details."""
+
+    assert context._captured_error is not None
+    message = str(context._captured_error)
+    assert f"within {context._wait_deadline}s" in message
diff --git a/features/steps/memory_service_coverage_steps.py b/features/steps/memory_service_coverage_steps.py
index 0ffcf079f..50a01c110 100644
--- a/features/steps/memory_service_coverage_steps.py
+++ b/features/steps/memory_service_coverage_steps.py
@@ -6,7 +6,7 @@ import asyncio
 import shutil
 import tempfile
 import time
-from datetime import UTC
+from datetime import UTC, datetime
 from pathlib import Path
 from typing import Any
 from unittest.mock import patch
@@ -24,6 +24,18 @@ from cleveragents.application.services.memory_service import (
 )
 
 
+def _wait_for_clock_advance(before: datetime, deadline_secs: float = 2.0) -> None:
+    """Spin until the UTC clock advances past ``before`` or raise on timeout."""
+
+    deadline = time.monotonic() + deadline_secs
+    while datetime.now(UTC) <= before:
+        if time.monotonic() > deadline:
+            raise AssertionError(
+                f"Clock did not advance past {before} within {deadline_secs}s"
+            )
+        time.sleep(0.001)
+
+
 @given("a conversation adapter configured to return text values")
 def step_adapter_returning_text(context: Any) -> None:
     """Create an adapter that returns buffer strings."""
@@ -434,7 +446,7 @@ def step_have_tracked_file_entity(context: Any, name: str) -> None:
 @when("I track the same entity again")
 def step_track_same_entity(context: Any) -> None:
     """Track the same entity again to update it."""
-    time.sleep(0.01)  # Small delay to ensure time difference
+    _wait_for_clock_advance(datetime.now(UTC))
     context.tracked_entity = context.memory_service.track_entity(
         context.tracked_entity.name, context.tracked_entity.entity_type
     )
@@ -503,9 +515,9 @@ def step_memory_service_entities_over_time(context: Any) -> None:
 
     # Track entities with small delays to ensure different timestamps
     context.memory_service.track_entity("oldest", EntityType.PROJECT)
-    time.sleep(0.01)
+    _wait_for_clock_advance(datetime.now(UTC))
     context.memory_service.track_entity("middle", EntityType.PLAN)
-    time.sleep(0.01)
+    _wait_for_clock_advance(datetime.now(UTC))
     context.memory_service.track_entity("newest", EntityType.FILE)
 
 
@@ -760,7 +772,7 @@ def step_track_project_with_initial_metadata(context: Any, name: str) -> None:
 @when("I track the same project entity again with additional metadata")
 def step_track_same_entity_with_additional_metadata(context: Any) -> None:
     """Track the same entity with additional metadata to trigger update."""
-    time.sleep(0.01)  # Small delay to ensure time difference
+    _wait_for_clock_advance(datetime.now(UTC))
     additional_metadata = {"status": "active", "priority": "high"}
     context.tracked_entity = context.memory_service.track_entity(
         context.entity_name, EntityType.PROJECT, additional_metadata