diff --git a/alembic/versions/0056_task_kind.py b/alembic/versions/0056_task_kind.py
new file mode 100644
index 0000000..fa07d18
--- /dev/null
+++ b/alembic/versions/0056_task_kind.py
@@ -0,0 +1,35 @@
+"""task_kind column on notes: distinguishes plan-tasks from work-tasks
+
+Revision ID: 0056
+Revises: 0055
+Create Date: 2026-05-28
+
+A plan is a Task (a note with non-null status) marked task_kind='plan'.
+The CHECK constraint lands in the same migration as the value set, per the
+'new CHECK-enum values need a same-change migration' rule.
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+revision = "0056"
+down_revision = "0055"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "notes",
+        sa.Column(
+            "task_kind", sa.Text(), nullable=False, server_default="work",
+        ),
+    )
+    op.create_check_constraint(
+        "notes_task_kind_check", "notes", "task_kind IN ('work','plan')",
+    )
+
+
+def downgrade() -> None:
+    op.drop_constraint("notes_task_kind_check", "notes", type_="check")
+    op.drop_column("notes", "task_kind")