diff --git a/dipy/workflows/denoise.py b/dipy/workflows/denoise.py
index 6771be13ef..64b367a6d1 100644
--- a/dipy/workflows/denoise.py
+++ b/dipy/workflows/denoise.py
@@ -316,7 +316,7 @@ def get_short_name(cls):
     @deprecated_params('num_threads', 'num_processes', since='1.4',
                        until='1.5')
     def run(self, input_files, slice_axis=2, n_points=3, num_processes=1,
-            out_dir='', out_unring='dwi_unrig.nii.gz'):
+            out_dir='', out_unring='dwi_unring.nii.gz'):
         r"""Workflow for applying Gibbs Ringing method.
 
         Parameters
@@ -337,7 +337,7 @@ def run(self, input_files, slice_axis=2, n_points=3, num_processes=1,
             use as many cores as possible). 0 raises an error.
         out_dir : string, optional
             Output directory. (default current directory)
-        out_unrig : string, optional
+        out_unring : string, optional
             Name of the resulting denoised volume.
 
         References
diff --git a/dipy/workflows/multi_io.py b/dipy/workflows/multi_io.py
index 0a319450ab..0d7be44877 100644
--- a/dipy/workflows/multi_io.py
+++ b/dipy/workflows/multi_io.py
@@ -36,12 +36,12 @@ def connect_output_paths(inputs, out_dir, out_files,
         The output directory.
     out_files : array
         List of output files.
-    output_strategy : string
+    output_strategy : string, optional
         Which strategy to use to generate the output paths.
             'append': Add out_dir to the path of the input.
             'prepend': Add the input path directory tree to out_dir.
             'absolute': Put directly in out_dir.
-    mix_names : bool
+    mix_names : bool, optional
         Whether or not prepend a string composed of a mix of the input
         names to the final output name.
 
@@ -130,10 +130,12 @@ def io_iterator(inputs, out_dir, fnames, output_strategy='absolute',
         Output directory.
     fnames : array
         File names of all outputs to be created.
-    output_strategy : string
+    output_strategy : string, optional
         Controls the behavior of the IOIterator for output paths.
-    mix_names : bool
+    mix_names : bool, optional
         Whether or not to append a mix of input names at the beginning.
+    out_keys : list, optional
+        Output parameter names.
 
     Returns
     -------