support default deployments

litellm/router_strategy/tag_based_routing.py

@@ -1,5 +1,9 @@
 """
-Use this to route requests between free and paid tiers
+Use this to route requests between Teams
+
+- If tags in request is a subset of tags in deployment, return deployment
+- if deployments are set with default tags, return all default deployment
+- If no default_deployments are set, return all deployments
 """
 
 from typing import TYPE_CHECKING, Any, Dict, List, Literal, Optional, TypedDict, Union
@@ -68,9 +72,26 @@ async def get_deployments_for_tag(
                         request_tags,
                     )
                     new_healthy_deployments.append(deployment)
+                elif "default" in deployment_tags:
+                    verbose_logger.debug(
+                        "adding default deployment with tags: %s, request tags: %s",
+                        deployment_tags,
+                        request_tags,
+                    )
+                    new_healthy_deployments.append(deployment)
 
             return new_healthy_deployments
 
+    # for Untagged requests use default deployments if set
+    _default_deployments_with_tags = []
+    for deployment in healthy_deployments:
+        if "default" in deployment.get("litellm_params", {}).get("tags", []):
+            _default_deployments_with_tags.append(deployment)
+
+    if len(_default_deployments_with_tags) > 0:
+        return _default_deployments_with_tags
+
+    # if no default deployment is found, return healthy_deployments
     verbose_logger.debug(
         "no tier found in metadata, returning healthy_deployments: %s",
         healthy_deployments,