Revert "fix: remove anthropic-beta header for Vertex AI requests with prompt caching" (#14421)

Author: ishaan-jaff

litellm/llms/anthropic/common_utils.py

@@ -107,10 +107,8 @@ def get_anthropic_headers(
         user_anthropic_beta_headers: Optional[List[str]] = None,
     ) -> dict:
         betas = set()
-        # Note: prompt-caching-2024-07-31 header is no longer required for prompt caching
-        # as per current Anthropic documentation. It's now generally available.
-        # if prompt_caching_set:
-        #     betas.add("prompt-caching-2024-07-31")
+        if prompt_caching_set:
+            betas.add("prompt-caching-2024-07-31")
         if computer_tool_used:
             betas.add("computer-use-2024-10-22")
         # if pdf_used:
@@ -178,11 +176,6 @@ def validate_environment(
             mcp_server_used=mcp_server_used,
         )
 
-        # For Vertex AI requests, remove any user-provided anthropic-beta headers
-        # since Vertex AI rejects them and they're no longer required for prompt caching
-        if optional_params.get("is_vertex_request", False):
-            headers = {k: v for k, v in headers.items() if k != "anthropic-beta"}
-        
         headers = {**headers, **anthropic_headers}
 
         return headers

tests/litellm/llms/anthropic/test_vertex_ai_prompt_caching_fix.py

@@ -10,7 +10,7 @@
 import litellm.litellm_core_utils.prompt_templates.factory
 
 load_dotenv()
-from unittest.mock import MagicMock, patch
+from unittest.mock import MagicMock
 
 sys.path.insert(
     0, os.path.abspath("../..")