diff --git a/python/gtsam/utils/plot.py b/python/gtsam/utils/plot.py
index a56face0c..2eaf889bb 100644
--- a/python/gtsam/utils/plot.py
+++ b/python/gtsam/utils/plot.py
@@ -312,7 +312,7 @@ def plot_pose3(
     Args:
         fignum: Integer representing the figure number to use for plotting.
         pose (gtsam.Pose3): 3D pose to be plotted.
-        axis_length:
+        axis_length: The length of the camera axes.
         P: Marginal covariance matrix to plot the uncertainty of the estimation.
         axis_labels: List of axis labels to set.