diff --git a/litellm/llms/base_llm/search/transformation.py b/litellm/llms/base_llm/search/transformation.py
index fad4be538c7..59039d68ede 100644
--- a/litellm/llms/base_llm/search/transformation.py
+++ b/litellm/llms/base_llm/search/transformation.py
@@ -180,12 +180,12 @@ class BaseSearchConfig:
 
     def sign_request(
         self,
-        headers: dict,  # mutable-ok: matches the request header dict every other hook on this base takes
-        optional_params: dict,  # mutable-ok: matches the optional params dict every other hook on this base takes
-        request_data: dict | list[dict],  # mutable-ok: matches transform_search_request's JSON body return type
+        headers: dict[str, str],  # mutable-ok: matches the request header dict every other hook on this base takes
+        optional_params: dict[str, object],  # mutable-ok: matches every other hook on this base
+        request_data: dict[str, object] | list[dict[str, object]],  # mutable-ok: transform_search_request's body
         api_base: str,
         api_key: str | None = None,
-    ) -> tuple[dict, bytes | None]:  # mutable-ok: the handler passes these headers straight to httpx
+    ) -> tuple[dict[str, str], bytes | None]:  # mutable-ok: the handler passes these headers straight to httpx
         """
         OPTIONAL
 
diff --git a/litellm/llms/bedrock/search/transformation.py b/litellm/llms/bedrock/search/transformation.py
index f6d852ffb0a..ca9759ed151 100644
--- a/litellm/llms/bedrock/search/transformation.py
+++ b/litellm/llms/bedrock/search/transformation.py
@@ -221,12 +221,12 @@ class AgentCoreSearchConfig(BaseSearchConfig, BaseAWSLLM):
 
     def sign_request(
         self,
-        headers: dict,  # mutable-ok: BaseSearchConfig hands providers the mutable request header dict
-        optional_params: dict,  # mutable-ok: BaseSearchConfig passes optional params as a dict
-        request_data: dict | list[dict],  # mutable-ok: BaseSearchConfig request bodies are JSON dicts
+        headers: dict[str, str],  # mutable-ok: BaseSearchConfig hands providers the mutable request header dict
+        optional_params: dict[str, object],  # mutable-ok: BaseSearchConfig passes optional params as a dict
+        request_data: dict[str, object] | list[dict[str, object]],  # mutable-ok: request bodies are JSON dicts
         api_base: str,
         api_key: str | None = None,
-    ) -> tuple[dict, bytes | None]:  # mutable-ok: BaseSearchConfig.sign_request returns httpx headers
+    ) -> tuple[dict[str, str], bytes | None]:  # mutable-ok: BaseSearchConfig.sign_request returns httpx headers
         """
         Authenticate the MCP request.
 
diff --git a/litellm/llms/custom_httpx/llm_http_handler.py b/litellm/llms/custom_httpx/llm_http_handler.py
index 3ee79241d30..b2f8c21d83c 100644
--- a/litellm/llms/custom_httpx/llm_http_handler.py
+++ b/litellm/llms/custom_httpx/llm_http_handler.py
@@ -1755,7 +1755,7 @@ class BaseLLMHTTPHandler:
             additional_args={
                 "complete_input_dict": data,
                 "api_base": complete_url,
-                "headers": signed_headers,
+                "headers": headers,
             },
         )
 
@@ -1848,7 +1848,7 @@ class BaseLLMHTTPHandler:
             additional_args={
                 "complete_input_dict": data,
                 "api_base": complete_url,
-                "headers": signed_headers,
+                "headers": headers,
             },
         )