wip(394): steps 6+7 — backend path and instruction surfaces

src/scribe/models/rulebook.py

@@ -19,9 +19,6 @@ class Rulebook(Base, TimestampMixin, SoftDeleteMixin):
     )
     title: Mapped[str] = mapped_column(Text)
     description: Mapped[str | None] = mapped_column(Text, nullable=True)
-    always_on: Mapped[bool] = mapped_column(
-        Boolean, default=False, nullable=False, server_default="false"
-    )
 
     def to_dict(self) -> dict:
         return {
@@ -29,7 +26,6 @@ class Rulebook(Base, TimestampMixin, SoftDeleteMixin):
             "owner_user_id": self.owner_user_id,
             "title": self.title,
             "description": self.description or "",
-            "always_on": self.always_on,
             "created_at": iso(self.created_at),
             "updated_at": iso(self.updated_at),
         }
@@ -96,16 +92,15 @@ class Rule(Base, TimestampMixin, SoftDeleteMixin):
     # WHEN this rule applies — the trigger, not the instruction. Required of
     # new rules at the service layer and nullable here, because rules written
     # before migration 0088 have none and a migration cannot invent one.
-    # It carries three jobs at once (note 3026): it is the tier test made
-    # concrete, the readable form of the canon tag, and the half of the
-    # document that makes a rule findable by meaning.
+    # It carries three jobs at once (note 3026): it is the readable form of
+    # the canon tag, the half of the document that makes a rule findable by
+    # meaning, and — since milestone 394 removed the always-on tier — the ONLY
+    # thing that decides whether a rule ever reaches a session at all. A rule
+    # with no trigger is not a quiet rule, it is an unreachable one.
     when_to_apply: Mapped[str | None] = mapped_column(Text, nullable=True)
-    # always_on = preloaded into every session, as every rule is today.
-    # conditional = reachable, and surfaced when its trigger fires. The
-    # default preserves existing behaviour exactly: nothing stops binding
-    # because of an upgrade. CHECK ck_rules_tier (migration 0088, rule 36).
-    tier: Mapped[str] = mapped_column(Text, default="always_on", server_default="always_on")
-    # WHAT KIND of instruction this is — force, where `tier` is delivery.
+    # WHAT KIND of instruction this is. `tier` used to sit beside this and
+    # carry delivery; milestone 394 removed it, so kind is now the only axis
+    # on a rule and delivery belongs entirely to retrieval.
     # `rule` must be FOLLOWED: ignoring it breaks something or crosses a
     # boundary. `preference` is how this person wants work DONE: ignoring it
     # costs consistency, not correctness.
@@ -161,7 +156,6 @@ class Rule(Base, TimestampMixin, SoftDeleteMixin):
             "title": self.title,
             "statement": self.statement,
             "when_to_apply": self.when_to_apply or "",
-            "tier": self.tier,
             # Unconditional, unlike the `if present` keys below. A reader
             # deciding how much force a record carries must never infer it
             # from an ABSENT key: "no kind field" and "kind is rule" would be
@@ -266,7 +260,7 @@ project_rule_suppressions = Table(
 # sibling of the two suppression tables below, one level up. Always-on
 # rulebooks bind every project implicitly; an inception decision can exclude
 # specific ones for this project, and get_applicable_rules /
-# list_always_on_rules(project_id) skip them. FKs CASCADE like the others.
+# get_applicable_rules(project_id) skips them. FKs CASCADE like the others.
 project_rulebook_exclusions = Table(
     "project_rulebook_exclusions",
     Base.metadata,