Update src/services/metrics_service.py

src/services/metrics_service.py

@@ -33,6 +33,8 @@ _DEFAULT_STATE: Dict[str, Any] = {
     "last_updated": 0.0,
 }
 
+_MAX_QUERY_LOG = 200  # keep last 200 queries in memory
+
 
 class MetricsService:
     def __init__(self, path: Path):
@@ -45,12 +47,47 @@ class MetricsService:
         self._buckets: Dict[str, Dict[str, int]] = {}
         self._dirty = False
 
+        # In-memory query log (last N queries, never flushed to disk)
+        self._query_log: list = []
+
         # Seed disk file if it doesn't exist
         if not self.path.exists():
             self._write_to_disk(dict(_DEFAULT_STATE))
 
     # ── Public API (sync, no I/O) ──────────────────────────────────────────────
 
+    def log_query(
+        self,
+        question: str,
+        intent: str = "",
+        tool: str = "",
+        model: str = "",
+        response_time: float = 0.0,
+        result_count: int = 0,
+        error: str = "",
+    ) -> None:
+        """Append a query record to the in-memory log (capped at _MAX_QUERY_LOG)."""
+        import datetime
+        record = {
+            "timestamp": datetime.datetime.utcnow().strftime("%Y-%m-%d %H:%M:%S"),
+            "question": (question or "")[:120],
+            "intent": intent or "",
+            "tool": tool or "",
+            "model": model or "",
+            "response_time": round(response_time, 2),
+            "result_count": result_count,
+            "error": (error or "")[:80],
+        }
+        self._query_log.append(record)
+        if len(self._query_log) > _MAX_QUERY_LOG:
+            self._query_log = self._query_log[-_MAX_QUERY_LOG:]
+
+    def recent_queries(self, limit: int = 50) -> list:
+        """Return the most recent `limit` query records, newest first."""
+        return list(reversed(self._query_log[-limit:]))
+
+    # ── Public API (sync, no I/O) ──────────────────────────────────────────────
+
     def incr(self, key: str, amount: int = 1) -> None:
         """Increment a top-level counter in memory."""
         self._counters[key] = self._counters.get(key, 0) + amount