diff --git a/examples/semantic-vocabulary-drift-smoke.py b/examples/semantic-vocabulary-drift-smoke.py
index d23bad3061..33aa60ed72 100755
--- a/examples/semantic-vocabulary-drift-smoke.py
+++ b/examples/semantic-vocabulary-drift-smoke.py
@@ -145,8 +145,8 @@
 TWIN_ROOT_ANCHOR = "loopx/control_plane"
 TWIN_BUDGET_ANCHOR = 43
 BUDGET_ANCHOR = {
-    "same_runtime_forks": 20,
-    "same_runtime_fork_definitions": 47,
+    "same_runtime_forks": 18,
+    "same_runtime_fork_definitions": 41,
     "conflicting_values": 18,
     "conflicting_definitions": 59,
     "schema_version_same_runtime_forks": 7,
@@ -154,7 +154,7 @@
     "multi_value_forks": 4,
     "multi_value_forks_semantic": 3,
     "multi_value_fork_definitions": 10,
-    "same_runtime_forks_semantic": 13,
+    "same_runtime_forks_semantic": 11,
     "conflicting_values_semantic": 0,
 }
 # Budgets for the legacy should-run decision fields, anchored the same way so a
diff --git a/loopx/control_plane/goals/goal_frontier/__init__.py b/loopx/control_plane/goals/goal_frontier/__init__.py
index bb42ee15ea..b403a96fb0 100644
--- a/loopx/control_plane/goals/goal_frontier/__init__.py
+++ b/loopx/control_plane/goals/goal_frontier/__init__.py
@@ -11,7 +11,13 @@
 from ...agents.profile import agent_profile_requires_vision
 from ...agents.runtime_model import peer_work_key, select_peer_for_work
 from ...runtime.time import parse_timestamp
-from ...todos.contract import normalize_todo_replan_obligation_id
+# Refs #4447: the todo contract owns this vocabulary; import it instead of
+# restating the literal in every module that classifies a Todo.
+from ...todos.contract import (
+    TODO_TASK_CLASS_ADVANCEMENT,
+    TODO_TASK_CLASS_MONITOR,
+    normalize_todo_replan_obligation_id,
+)
 from ...todos.todo_semantics import (
     todo_advancement_frontier_counts,
     todo_item_is_watch_only_monitor,
@@ -99,8 +105,6 @@
 MONITOR_NO_CHANGE_STREAK_TRIGGER = "monitor_no_change_streak"
 VISION_PROFILE_MISSING_TRIGGER = "required_agent_vision_missing"
 TODO_SUCCESSION_GAP_TRIGGER = TODO_SUCCESSION_WARNING_REASON_CODE
-TODO_TASK_CLASS_ADVANCEMENT = "advancement_task"
-TODO_TASK_CLASS_MONITOR = "continuous_monitor"
 
 
 def safe_non_negative_int(value: Any) -> int:
diff --git a/loopx/control_plane/goals/goal_frontier/long_todo_chain.py b/loopx/control_plane/goals/goal_frontier/long_todo_chain.py
index 8b6d0df0bd..dd506e0fff 100644
--- a/loopx/control_plane/goals/goal_frontier/long_todo_chain.py
+++ b/loopx/control_plane/goals/goal_frontier/long_todo_chain.py
@@ -18,7 +18,6 @@
 
 
 LONG_TODO_CHAIN_TRIGGER = "long_todo_chain"
-TODO_TASK_CLASS_ADVANCEMENT = "advancement_task"
 LONG_TODO_CHAIN_FRONTIER_REVISION_SCHEMA_VERSION = (
     TODO_FRONTIER_REVISION_SCHEMA_VERSION
 )
diff --git a/loopx/control_plane/todos/frontier_revision.py b/loopx/control_plane/todos/frontier_revision.py
index f76febcb92..6bf1a659ad 100644
--- a/loopx/control_plane/todos/frontier_revision.py
+++ b/loopx/control_plane/todos/frontier_revision.py
@@ -8,13 +8,18 @@
 from typing import Any
 
 from ..effect_runtime import effect_runtime_result
-from .contract import normalize_todo_claimed_by, normalize_todo_excluded_agents
+# Refs #4447: the todo contract owns this vocabulary; import it instead of
+# restating the literal in every module that classifies a Todo.
+from .contract import (
+    TODO_TASK_CLASS_ADVANCEMENT,
+    normalize_todo_claimed_by,
+    normalize_todo_excluded_agents,
+)
 from .todo_semantics import todo_item_task_class
 
 
 TODO_FRONTIER_REVISION_SCHEMA_VERSION = "todo_frontier_revision_v0"
 TODO_FRONTIER_REVISION_INDEX_SCHEMA_VERSION = "todo_frontier_revision_index_v0"
-TODO_TASK_CLASS_ADVANCEMENT = "advancement_task"
 
 FRONTIER_REVISION_FIELDS = (
     "todo_id",
diff --git a/loopx/semantics/vocabulary_v0.json b/loopx/semantics/vocabulary_v0.json
index bc8a41835b..203c8ddf9f 100644
--- a/loopx/semantics/vocabulary_v0.json
+++ b/loopx/semantics/vocabulary_v0.json
@@ -886,15 +886,15 @@
   },
   "inventory_ratchets": {
     "meaning": "Counts read from the generated inventory. A same-runtime fork is one constant name with one value defined in two or more modules of the same runtime; a conflicting value is one name with different values. Both the number of affected names and the number of definitions are budgets, so a third spelling of an already-conflicting name is still a regression.",
-    "same_runtime_forks": 20,
-    "same_runtime_fork_definitions": 47,
+    "same_runtime_forks": 18,
+    "same_runtime_fork_definitions": 41,
     "conflicting_values": 18,
     "conflicting_definitions": 59,
     "schema_version_same_runtime_forks": 7,
     "multi_value_twins": 13,
     "multi_value_forks": 4,
     "multi_value_fork_definitions": 10,
-    "same_runtime_forks_semantic": 13,
+    "same_runtime_forks_semantic": 11,
     "conflicting_values_semantic": 0,
     "multi_value_meaning": "Enums, named closed sets, Literal aliases, and TypeScript as-const arrays are vocabulary exactly as a NAME = \"value\" constant is, so they get the same collision rule. One name defined in two modules with identical values is a twin; with different values it is a fork. The semantic multi-value-fork budget excludes only names declared in scope_declarations.",
     "multi_value_forks_note": "The 4 counted forks include SOURCE_SURFACES, whose four definitions are four CLI commands each listing its own data sources; that is bounded-context reuse of one name, not drift. It stays in the budget until M0.5 adds a scope field (RFC Section 5) and must not be removed by renaming.",