add basic cohere rerank

litellm/__init__.py

@@ -934,6 +934,7 @@ from .proxy.proxy_cli import run_server
 from .router import Router
 from .assistants.main import *
 from .batches.main import *
+from .rerank_api.main import *
 from .fine_tuning.main import *
 from .files.main import *
 from .scheduler import *

litellm/rerank_api/types.py

@@ -0,0 +1,20 @@
+"""
+LiteLLM Follows the cohere API format for the re rank API
+https://docs.cohere.com/reference/rerank
+
+"""
+
+from pydantic import BaseModel
+
+
+class RerankRequest(BaseModel):
+    model: str
+    query: str
+    top_n: int
+    documents: list[str]
+
+
+class RerankResponse(BaseModel):
+    id: str
+    results: list[dict]  # Contains index and relevance_score
+    meta: dict  # Contains api_version and billed_units