diff --git a/src/google/adk/agents/readonly_context.py b/src/google/adk/agents/readonly_context.py
index 1e3b9aa2..54842536 100644
--- a/src/google/adk/agents/readonly_context.py
+++ b/src/google/adk/agents/readonly_context.py
@@ -23,7 +23,6 @@ if TYPE_CHECKING:
   from google.genai import types
 
   from .invocation_context import InvocationContext
-  from ..auth.credential_service.base_credential_service import BaseCredentialService
 
 
 class ReadonlyContext:
@@ -53,8 +52,3 @@ class ReadonlyContext:
   def state(self) -> MappingProxyType[str, Any]:
     """The state of the current session. READONLY field."""
     return MappingProxyType(self._invocation_context.session.state)
-
-  @property
-  def credential_service(self) -> Optional[BaseCredentialService]:
-    """The credential service for the current invocation."""
-    return self._invocation_context.credential_service