diff --git a/libs/core/langchain_core/callbacks/manager.py b/libs/core/langchain_core/callbacks/manager.py
index cd26f49f5b6..31aa2ac156f 100644
--- a/libs/core/langchain_core/callbacks/manager.py
+++ b/libs/core/langchain_core/callbacks/manager.py
@@ -94,7 +94,9 @@ def trace_as_chain_group(
             manager.on_chain_end({"output": res})
         ```
     """
-    from langchain_core.tracers.context import _get_trace_callbacks  # noqa: PLC0415
+    from langchain_core.tracers.context import (  # noqa: PLC0415 -- deferred to avoid importing langsmith at module level
+        _get_trace_callbacks,
+    )
 
     cb = _get_trace_callbacks(
         project_name, example_id, callback_manager=callback_manager
@@ -175,7 +177,9 @@ async def atrace_as_chain_group(
             await manager.on_chain_end({"output": res})
         ```
     """
-    from langchain_core.tracers.context import _get_trace_callbacks  # noqa: PLC0415
+    from langchain_core.tracers.context import (  # noqa: PLC0415 -- deferred to avoid importing langsmith at module level
+        _get_trace_callbacks,
+    )
 
     cb = _get_trace_callbacks(
         project_name, example_id, callback_manager=callback_manager
@@ -2319,6 +2323,7 @@ def _configure(
     Returns:
         The configured callback manager.
     """
+    # Deferred to avoid importing langsmith at module level (~132ms).
     from langsmith.run_helpers import get_tracing_context  # noqa: PLC0415
 
     from langchain_core.tracers.context import (  # noqa: PLC0415
diff --git a/libs/core/langchain_core/runnables/config.py b/libs/core/langchain_core/runnables/config.py
index 2a19dea8e21..b538ff9fa05 100644
--- a/libs/core/langchain_core/runnables/config.py
+++ b/libs/core/langchain_core/runnables/config.py
@@ -158,6 +158,7 @@ def _set_config_context(
     Returns:
         The token to reset the config and the previous tracing context.
     """
+    # Deferred to avoid importing langsmith at module level (~132ms).
     from langsmith.run_helpers import (  # noqa: PLC0415
         _set_tracing_context,
         get_tracing_context,
@@ -199,6 +200,7 @@ def set_config_context(config: RunnableConfig) -> Generator[Context, None, None]
     Yields:
         The config context.
     """
+    # Deferred to avoid importing langsmith at module level (~132ms).
     from langsmith.run_helpers import _set_tracing_context  # noqa: PLC0415
 
     ctx = copy_context()