diff --git a/ansible_mitogen/planner.py b/ansible_mitogen/planner.py
index 11531e4a..8d216af1 100644
--- a/ansible_mitogen/planner.py
+++ b/ansible_mitogen/planner.py
@@ -53,6 +53,9 @@ import ansible_mitogen.services
 
 
 LOG = logging.getLogger(__name__)
+NO_METHOD_MSG = 'Mitogen: no invocation method found for: '
+CRASHED_MSG = 'Mitogen: internal error: '
+NO_INTERPRETER_MSG = 'module (%s) is missing interpreter line'
 
 
 def parse_script_interpreter(source):
@@ -62,7 +65,7 @@ def parse_script_interpreter(source):
 
     :returns:
         Tuple of `(interpreter, arg)`, where `intepreter` is the script
-        interpreter and `arg` is its solve argument if present, otherwise
+        interpreter and `arg` is its sole argument if present, otherwise
         :py:data:`None`.
     """
     # Linux requires first 2 bytes with no whitespace, pretty sure it's the
@@ -305,11 +308,6 @@ _planners = [
 ]
 
 
-NO_METHOD_MSG = 'Mitogen: no invocation method found for: '
-CRASHED_MSG = 'Mitogen: internal error: '
-NO_INTERPRETER_MSG = 'module (%s) is missing interpreter line'
-
-
 def get_module_data(name):
     path = module_loader.find_plugin(name, '')
     with open(path, 'rb') as fp: