Rename custom code to RetrievalRouter

configuration_retrievalrouter.py

@@ -0,0 +1,26 @@
+"""RetrievalRouter Configuration."""
+from transformers import PretrainedConfig
+
+# Standalone copy of train.config.ARM_NAMES: this module is uploaded to the Hub and loaded
+# via trust_remote_code, so it cannot import from the training package.
+STRATEGY_NAMES = ["MULTIMODAL_RERANK", "MULTIMODAL-SINGLE", "TEXT_RERANK", "TEXT-SINGLE", "BM25"]
+
+
+class RetrievalRouterConfig(PretrainedConfig):
+    """Configuration for RetrievalRouter - a query-aware retrieval router."""
+    model_type = "retrievalrouter"
+
+    def __init__(
+        self,
+        base_model_name: str = "Qwen/Qwen3-0.6B-Base",
+        hidden_size: int = 1024,
+        num_labels: int = 5,
+        classifier_dropout: float = 0.1,
+        strategy_names: list = None,
+        **kwargs,
+    ):
+        super().__init__(num_labels=num_labels, **kwargs)
+        self.base_model_name = base_model_name
+        self.hidden_size = hidden_size
+        self.classifier_dropout = classifier_dropout
+        self.strategy_names = strategy_names or STRATEGY_NAMES