diff --git a/lisp/ob-processing.el b/lisp/ob-processing.el
index 460e6e381..ff506e4d9 100644
--- a/lisp/ob-processing.el
+++ b/lisp/ob-processing.el
@@ -118,7 +118,7 @@
       (message "Not inside a Processing source block."))))
 
 (defun org-babel-execute:processing (body params)
-  "Execute a block of Processing code.
+  "Execute Processing code BODY according to PARAMS.
 This function is called by `org-babel-execute-src-block'."
   (let ((sketch-code
 	 (org-babel-expand-body:generic
@@ -144,7 +144,8 @@ Processing does not support sessions."
   (error "Processing does not support sessions"))
 
 (defun org-babel-variable-assignments:processing (params)
-  "Return list of processing statements assigning the block's variables."
+  "Return list of processing statements assigning the block's variables.
+The variable assignments are defined in PARAMS."
   (mapcar #'org-babel-processing-var-to-processing
 	  (org-babel--get-vars params)))