diff --git a/apps/api/src/jobs/backup_restore_legacy_backfill_job.py b/apps/api/src/jobs/backup_restore_legacy_backfill_job.py
index 04060260c..4d37f9ff5 100644
--- a/apps/api/src/jobs/backup_restore_legacy_backfill_job.py
+++ b/apps/api/src/jobs/backup_restore_legacy_backfill_job.py
@@ -46,7 +46,10 @@ BACKFILL_IDEMPOTENCY_CHANNEL = "backup_restore_backfill"
 BACKFILL_DB_CONTRACT_REPAIR_GENERATION = "cost_usd_state_bind_v1"
 LIVE_RECONCILE_SCHEMA_VERSION = "backup_restore_outbound_reconciler_v1"
 LIVE_RECONCILE_AGENT_ID = "backup_restore_outbound_reconciler"
-LIVE_RECONCILE_IDEMPOTENCY_CHANNEL = "backup_restore_outbound_reconcile"
+# ``awooop_run_idempotency.channel_type`` is VARCHAR(32).  Keep this durable
+# identity explicit and below that limit; the previous 33-character value
+# caused PostgreSQL 22001 before a live backup card could be claimed.
+LIVE_RECONCILE_IDEMPOTENCY_CHANNEL = "backup_restore_live_reconcile"
 BACKUP_RESTORE_EVENT_TYPE = "backup_restore_escrow_signal"
 BACKUP_RESTORE_LANE = "backup_restore_escrow_triage"
 PROJECTION_SCHEMA_VERSION = "telegram_agent99_dispatch_receipt_projection_v1"
diff --git a/apps/api/tests/test_backup_restore_legacy_backfill_job.py b/apps/api/tests/test_backup_restore_legacy_backfill_job.py
index 88aee8c88..6d9b59de2 100644
--- a/apps/api/tests/test_backup_restore_legacy_backfill_job.py
+++ b/apps/api/tests/test_backup_restore_legacy_backfill_job.py
@@ -576,6 +576,16 @@ async def test_live_reconciler_reserves_only_unowned_incomplete_cards(
     assert "backup-signal:" in sql
 
 
+def test_live_reconciler_idempotency_channel_fits_durable_schema() -> None:
+    # awooop_run_idempotency.channel_type is VARCHAR(32).  This invariant must
+    # be checked without relying on a mock database, which cannot reproduce a
+    # production PostgreSQL 22001 truncation error.
+    assert job.LIVE_RECONCILE_IDEMPOTENCY_CHANNEL == (
+        "backup_restore_live_reconcile"
+    )
+    assert len(job.LIVE_RECONCILE_IDEMPOTENCY_CHANNEL) <= 32
+
+
 @pytest.mark.asyncio
 async def test_live_reconciler_projects_bounded_agent99_receipt(
     monkeypatch: pytest.MonkeyPatch,