specify default values in docs
diff --git a/tensorflow/python/data/experimental/service/server_lib.py b/tensorflow/python/data/experimental/service/server_lib.py
index 8c5c85a..bc9cf28 100644
--- a/tensorflow/python/data/experimental/service/server_lib.py
+++ b/tensorflow/python/data/experimental/service/server_lib.py
@@ -102,10 +102,10 @@
 
     Args:
       config: (Optional.) A `tf.data.experimental.service.DispatcherConfig`
-        configration. If `None`, the dispatcher will be use default
+        configration. If `None`, the dispatcher will use default
         configuration values.
       start: (Optional.) Boolean, indicating whether to start the server after
-        creating it.
+        creating it. Defaults to True.
     """
     config = config or DispatcherConfig()
     if config.fault_tolerant_mode and not config.work_dir:
@@ -196,7 +196,7 @@
     collections.namedtuple(
         "WorkerConfig",
         ["dispatcher_address", "worker_address", "port", "protocol"])):
-  """Configuration class for tf.data service dispatchers.
+  """Configuration class for tf.data service workers.
 
   Fields:
     dispatcher_address: Specifies the address of the dispatcher.
@@ -256,7 +256,7 @@
     Args:
       config: A `tf.data.experimental.service.WorkerConfig` configration.
       start: (Optional.) Boolean, indicating whether to start the server after
-        creating it.
+        creating it. Defaults to True.
     """
     if config.dispatcher_address is None:
       raise ValueError("must specify a dispatcher_address")