diff --git a/surfsense_backend/alembic/versions/138_add_thread_auto_model_pinning_fields.py b/surfsense_backend/alembic/versions/138_add_thread_auto_model_pinning_fields.py
index 6e4b77cc7..1ea549975 100644
--- a/surfsense_backend/alembic/versions/138_add_thread_auto_model_pinning_fields.py
+++ b/surfsense_backend/alembic/versions/138_add_thread_auto_model_pinning_fields.py
@@ -8,13 +8,6 @@ Add thread-level fields to persist Auto (Fastest) model pinning metadata:
 - pinned_llm_config_id: concrete resolved config id used for this thread
 - pinned_auto_mode: auto policy identifier (currently "auto_fastest")
 - pinned_at: timestamp when the pin was created/refreshed
-
-Idempotent: this migration was originally numbered 134 on the
-``feat/split-auto-free-premium`` branch and was renumbered to 138 during
-the merge with ``upstream/dev`` (which claimed 134-137). Some databases
-already have these columns/indexes from when the original 134 ran, so we
-use ``IF NOT EXISTS`` to make re-application a no-op for those DBs while
-still creating the schema on fresh databases.
 """
 
 from __future__ import annotations
diff --git a/surfsense_backend/tests/unit/test_stream_new_chat_contract.py b/surfsense_backend/tests/unit/test_stream_new_chat_contract.py
index 9f4280063..86ea7edd1 100644
--- a/surfsense_backend/tests/unit/test_stream_new_chat_contract.py
+++ b/surfsense_backend/tests/unit/test_stream_new_chat_contract.py
@@ -231,10 +231,18 @@ def test_network_send_failures_use_unified_retry_toast_message():
     assert 'userMessage: "Message not sent. Please retry."' in classifier_source
     assert 'userMessage: "Connection issue. Please try again."' in classifier_source
     assert "tagPreAcceptSendFailure(error)" in page_source
-    assert 'existingCode === "THREAD_BUSY"' in page_source
-    assert 'existingCode === "AUTH_EXPIRED"' in page_source
-    assert 'existingCode === "UNAUTHORIZED"' in page_source
-    assert 'existingCode === "RATE_LIMITED"' in page_source
+    assert "const passthroughCodes = new Set([" in page_source
+    assert '"PREMIUM_QUOTA_EXHAUSTED"' in page_source
+    assert '"THREAD_BUSY"' in page_source
+    assert '"AUTH_EXPIRED"' in page_source
+    assert '"UNAUTHORIZED"' in page_source
+    assert '"RATE_LIMITED"' in page_source
+    assert '"NETWORK_ERROR"' in page_source
+    assert '"STREAM_PARSE_ERROR"' in page_source
+    assert '"TOOL_EXECUTION_ERROR"' in page_source
+    assert '"PERSIST_MESSAGE_FAILED"' in page_source
+    assert '"SERVER_ERROR"' in page_source
+    assert "passthroughCodes.has(existingCode)" in page_source
     assert 'errorCode: "SEND_FAILED_PRE_ACCEPT"' in page_source
     assert 'errorCode: "NETWORK_ERROR"' not in page_source
     assert "Failed to start chat. Please try again." not in page_source
diff --git a/surfsense_web/app/dashboard/[search_space_id]/new-chat/[[...chat_id]]/page.tsx b/surfsense_web/app/dashboard/[search_space_id]/new-chat/[[...chat_id]]/page.tsx
index f21a0a30b..239afaf73 100644
--- a/surfsense_web/app/dashboard/[search_space_id]/new-chat/[[...chat_id]]/page.tsx
+++ b/surfsense_web/app/dashboard/[search_space_id]/new-chat/[[...chat_id]]/page.tsx
@@ -227,11 +227,21 @@ function tagPreAcceptSendFailure(error: unknown): unknown {
 	if (error instanceof Error) {
 		const withCode = error as Error & { errorCode?: string; code?: string };
 		const existingCode = withCode.errorCode ?? withCode.code;
+		const passthroughCodes = new Set([
+			"PREMIUM_QUOTA_EXHAUSTED",
+			"THREAD_BUSY",
+			"AUTH_EXPIRED",
+			"UNAUTHORIZED",
+			"RATE_LIMITED",
+			"NETWORK_ERROR",
+			"STREAM_PARSE_ERROR",
+			"TOOL_EXECUTION_ERROR",
+			"PERSIST_MESSAGE_FAILED",
+			"SERVER_ERROR",
+		]);
 		if (
-			existingCode === "THREAD_BUSY" ||
-			existingCode === "AUTH_EXPIRED" ||
-			existingCode === "UNAUTHORIZED" ||
-			existingCode === "RATE_LIMITED"
+			existingCode &&
+			passthroughCodes.has(existingCode)
 		) {
 			return Object.assign(error, { errorCode: existingCode });
 		}