diff --git a/lang_agent/config/db_config_manager.py b/lang_agent/config/db_config_manager.py
index bb5ce7c..e40102c 100644
--- a/lang_agent/config/db_config_manager.py
+++ b/lang_agent/config/db_config_manager.py
@@ -17,26 +17,48 @@ class DBConfigManager:
                 cur.execute("DELETE FROM prompt_sets WHERE pipeline_id = %s AND id = %s", (pipeline_id, prompt_set_id))
                 conn.commit()
 
-    def list_prompt_sets(self, pipeline_id: Optional[str] = None) -> List[Dict[str, object]]:
+    def list_prompt_sets(
+        self, pipeline_id: Optional[str] = None, graph_id: Optional[str] = None
+    ) -> List[Dict[str, object]]:
         """
         List prompt_set metadata for UI listing.
         """
         with psycopg.connect(self.conn_str) as conn:
             with conn.cursor(row_factory=dict_row) as cur:
-                if pipeline_id:
+                if pipeline_id and graph_id:
                     cur.execute(
                         """
-                        SELECT id, pipeline_id, name, description, is_active, created_at, updated_at, list
+                        SELECT id, pipeline_id, graph_id, name, description, is_active, created_at, updated_at, list
+                        FROM prompt_sets
+                        WHERE pipeline_id = %s AND graph_id = %s
+                        ORDER BY updated_at DESC, created_at DESC
+                        """,
+                        (pipeline_id, graph_id),
+                    )
+                elif pipeline_id:
+                    cur.execute(
+                        """
+                        SELECT id, pipeline_id, graph_id, name, description, is_active, created_at, updated_at, list
                         FROM prompt_sets
                         WHERE pipeline_id = %s
                         ORDER BY updated_at DESC, created_at DESC
                         """,
                         (pipeline_id,),
                     )
+                elif graph_id:
+                    cur.execute(
+                        """
+                        SELECT id, pipeline_id, graph_id, name, description, is_active, created_at, updated_at, list
+                        FROM prompt_sets
+                        WHERE graph_id = %s
+                        ORDER BY updated_at DESC, created_at DESC
+                        """,
+                        (graph_id,),
+                    )
                 else:
                     cur.execute(
                         """
-                        SELECT id, pipeline_id, name, description, is_active, created_at, updated_at, list
+                        SELECT id, pipeline_id, graph_id, name, description, is_active, created_at, updated_at, list
                         FROM prompt_sets
                         ORDER BY updated_at DESC, created_at DESC
                         """
@@ -47,6 +69,7 @@ class DBConfigManager:
             {
                 "prompt_set_id": str(row["id"]),
                 "pipeline_id": row["pipeline_id"],
+                "graph_id": row.get("graph_id"),
                 "name": row["name"],
                 "description": row["description"] or "",
                 "is_active": bool(row["is_active"]),
@@ -65,7 +88,7 @@ class DBConfigManager:
             with conn.cursor(row_factory=dict_row) as cur:
                 cur.execute(
                     """
-                    SELECT id, pipeline_id, name, description, is_active, created_at, updated_at, list
+                    SELECT id, pipeline_id, graph_id, name, description, is_active, created_at, updated_at, list
                     FROM prompt_sets
                     WHERE id = %s AND pipeline_id = %s
                     """,
@@ -79,6 +102,7 @@ class DBConfigManager:
         return {
             "prompt_set_id": str(row["id"]),
             "pipeline_id": row["pipeline_id"],
+            "graph_id": row.get("graph_id"),
             "name": row["name"],
             "description": row["description"] or "",
             "is_active": bool(row["is_active"]),
@@ -108,6 +132,7 @@ class DBConfigManager:
             resolved_set_id, tool_csv = self._resolve_prompt_set(
                 conn,
                 pipeline_id=pipeline_id,
+                graph_id=None,
                 prompt_set_id=prompt_set_id,
                 create_if_missing=False,
             )
@@ -131,6 +156,7 @@ class DBConfigManager:
     def set_config(
         self,
         pipeline_id: str,
+        graph_id: Optional[str],
         prompt_set_id: Optional[str],
         tool_list: Optional[Sequence[str]],
         prompt_dict: Optional[Mapping[str, str]],
@@ -150,6 +176,9 @@ class DBConfigManager:
         """
         if not pipeline_id:
             raise ValueError("pipeline_id is required")
+        normalized_graph_id = self._normalize_graph_id(graph_id)
+        if prompt_set_id is None and not normalized_graph_id:
+            raise ValueError("graph_id is required when creating a new prompt set")
 
         normalized_prompt_dict = self._normalize_prompt_dict(prompt_dict)
         tool_csv = self._join_tool_list(tool_list)
@@ -158,6 +187,7 @@ class DBConfigManager:
             resolved_set_id, _ = self._resolve_prompt_set(
                 conn,
                 pipeline_id=pipeline_id,
+                graph_id=normalized_graph_id,
                 prompt_set_id=prompt_set_id,
                 create_if_missing=prompt_set_id is None,
             )
@@ -170,10 +200,10 @@ class DBConfigManager:
                 cur.execute(
                     """
                     UPDATE prompt_sets
-                    SET list = %s, updated_at = now()
+                    SET list = %s, graph_id = COALESCE(%s, graph_id), updated_at = now()
                     WHERE id = %s
                     """,
-                    (tool_csv, resolved_set_id),
+                    (tool_csv, normalized_graph_id, resolved_set_id),
                 )
 
                 keys = list(normalized_prompt_dict.keys())
@@ -218,6 +248,7 @@ class DBConfigManager:
         self,
         conn: psycopg.Connection,
         pipeline_id: str,
+        graph_id: Optional[str],
         prompt_set_id: Optional[str],
         create_if_missing: bool,
     ) -> Tuple[Optional[str], str]:
@@ -255,12 +286,13 @@ class DBConfigManager:
 
             cur.execute(
                 """
-                INSERT INTO prompt_sets (pipeline_id, name, description, is_active, list)
-                VALUES (%s, %s, %s, %s, %s)
+                INSERT INTO prompt_sets (pipeline_id, graph_id, name, description, is_active, list)
+                VALUES (%s, %s, %s, %s, %s, %s)
                 RETURNING id, list
                 """,
                 (
                     pipeline_id,
+                    graph_id,
                     "default",
                     "Auto-created by DBConfigManager",
                     True,
@@ -302,4 +334,10 @@ class DBConfigManager:
             if not norm_key:
                 continue
             out[norm_key] = value if isinstance(value, str) else str(value)
-        return out
\ No newline at end of file
+        return out
+
+    def _normalize_graph_id(self, graph_id: Optional[str]) -> Optional[str]:
+        if graph_id is None:
+            return None
+        value = str(graph_id).strip()
+        return value or None
\ No newline at end of file