PR #22867 added _remove_scope_from_cache_control for Bedrock and Azur… (#23183)

* PR #22867 added _remove_scope_from_cache_control for Bedrock and Azure AI but omitted Vertex AI. This applies the same pattern to VertexAIPartnerModelsAnthropicMessagesConfig."

* PR #22867 added _remove_scope_from_cache_control for Bedrock and Azure AI but omitted Vertex AI. This applies the same pattern to VertexAIPartnerModelsAnthropicMessagesConfig."

* PR #22867 added _remove_scope_from_cache_control to AzureAnthropicMessagesConfig
 but missed VertexAIPartnerModelsAnthropicMessagesConfi Rather than duplicating the method again, moved it up to the base AnthropicMessagesConfig so all providers
  inherit it, and removed the now-redundant copy from the Azure AI subclass.

* PR #22867 added _remove_scope_from_cache_control to AzureAnthropicMessagesConfig
 but missed VertexAIPartnerModelsAnthropicMessagesConfi Rather than duplicating the method again, moved it up to the base AnthropicMessagesConfig so all providers
  inherit it, and removed the now-redundant copy from the Azure AI subclass.

---------

Co-authored-by: Krish Dholakia <krrishdholakia@gmail.com>

litellm/llms/anthropic/experimental_pass_through/messages/transformation.py

@@ -50,6 +50,38 @@ class AnthropicMessagesConfig(BaseAnthropicMessagesConfig):
             # "metadata",
         ]
 
+    def _remove_scope_from_cache_control(
+        self, anthropic_messages_request: Dict
+    ) -> None:
+        """
+        Remove `scope` field from cache_control blocks.
+
+        Some providers (Vertex AI, Azure AI Foundry) do not support the `scope`
+        field in cache_control (e.g. "global" for cross-request caching).
+        Processes both `system` and `messages` content blocks.
+        """
+
+        def _sanitize(cache_control: Any) -> None:
+            if isinstance(cache_control, dict):
+                cache_control.pop("scope", None)
+
+        def _process_content_list(content: list) -> None:
+            for item in content:
+                if isinstance(item, dict) and "cache_control" in item:
+                    _sanitize(item["cache_control"])
+
+        if "system" in anthropic_messages_request:
+            system = anthropic_messages_request["system"]
+            if isinstance(system, list):
+                _process_content_list(system)
+
+        if "messages" in anthropic_messages_request:
+            for message in anthropic_messages_request["messages"]:
+                if isinstance(message, dict) and "content" in message:
+                    content = message["content"]
+                    if isinstance(content, list):
+                        _process_content_list(content)
+
     @staticmethod
     def _filter_billing_headers_from_system(system_param):
         """

litellm/llms/vertex_ai/vertex_ai_partner_models/anthropic/experimental_pass_through/transformation.py

@@ -150,6 +150,8 @@ class VertexAIPartnerModelsAnthropicMessagesConfig(AnthropicMessagesConfig, Vert
             headers=headers,
         )
 
+        self._remove_scope_from_cache_control(anthropic_messages_request)
+
         anthropic_messages_request["anthropic_version"] = "vertex-2023-10-16"
 
         anthropic_messages_request.pop(

tests/test_litellm/llms/vertex_ai/vertex_ai_partner_models/anthropic/test_vertex_ai_partner_models_anthropic_messages_config.py

@@ -5,6 +5,7 @@ import pytest
 from litellm.llms.vertex_ai.vertex_ai_partner_models.anthropic.experimental_pass_through.transformation import (
     VertexAIPartnerModelsAnthropicMessagesConfig,
 )
+from litellm.types.router import GenericLiteLLMParams
 
 
 def test_validate_environment_uses_vertex_ai_location():
@@ -248,3 +249,47 @@ def test_validate_environment_with_authorization_header_calculates_api_base():
         # Verify Authorization header is still present
         assert "Authorization" in updated_headers, \
             "Authorization header should be preserved"
+
+
+def test_transform_anthropic_messages_request_removes_scope_from_cache_control():
+    """Ensure scope field is removed from cache_control for Vertex AI (not supported)."""
+    config = VertexAIPartnerModelsAnthropicMessagesConfig()
+
+    messages = [
+        {
+            "role": "user",
+            "content": [
+                {
+                    "type": "text",
+                    "text": "Hello",
+                    "cache_control": {"type": "ephemeral", "scope": "global"},
+                }
+            ],
+        }
+    ]
+    anthropic_messages_optional_request_params = {
+        "max_tokens": 1024,
+        "system": [
+            {
+                "type": "text",
+                "text": "You are an AI assistant.",
+                "cache_control": {"type": "ephemeral", "scope": "global"},
+            }
+        ],
+    }
+
+    result = config.transform_anthropic_messages_request(
+        model="claude-sonnet-4-6",
+        messages=messages,
+        anthropic_messages_optional_request_params=anthropic_messages_optional_request_params,
+        litellm_params=GenericLiteLLMParams(),
+        headers={},
+    )
+
+    # scope removed from system
+    assert "scope" not in result["system"][0]["cache_control"]
+    assert result["system"][0]["cache_control"]["type"] == "ephemeral"
+
+    # scope removed from message content
+    assert "scope" not in result["messages"][0]["content"][0]["cache_control"]
+    assert result["messages"][0]["content"][0]["cache_control"]["type"] == "ephemeral"