Implement KB features with codex

engine/app/backend_client.py

@@ -2,7 +2,7 @@
 
 from __future__ import annotations
 
-from typing import Any, Dict, Optional
+from typing import Any, Dict, List, Optional
 
 import aiohttp
 from loguru import logger
@@ -146,3 +146,46 @@ async def finalize_history_call_record(
     except Exception as exc:
         logger.warning(f"Failed to finalize history call record ({call_id}): {exc}")
         return False
+
+
+async def search_knowledge_context(
+    *,
+    kb_id: str,
+    query: str,
+    n_results: int = 5,
+) -> List[Dict[str, Any]]:
+    """Search backend knowledge base and return retrieval results."""
+    base_url = _backend_base_url()
+    if not base_url:
+        return []
+    if not kb_id or not query.strip():
+        return []
+    try:
+        safe_n_results = max(1, int(n_results))
+    except (TypeError, ValueError):
+        safe_n_results = 5
+
+    url = f"{base_url}/api/knowledge/search"
+    payload: Dict[str, Any] = {
+        "kb_id": kb_id,
+        "query": query,
+        "nResults": safe_n_results,
+    }
+
+    try:
+        async with aiohttp.ClientSession(timeout=_timeout()) as session:
+            async with session.post(url, json=payload) as resp:
+                if resp.status == 404:
+                    logger.warning(f"Knowledge base not found for retrieval: {kb_id}")
+                    return []
+                resp.raise_for_status()
+                data = await resp.json()
+                if not isinstance(data, dict):
+                    return []
+                results = data.get("results", [])
+                if not isinstance(results, list):
+                    return []
+                return [r for r in results if isinstance(r, dict)]
+    except Exception as exc:
+        logger.warning(f"Knowledge search failed (kb_id={kb_id}): {exc}")
+        return []