Snippets to query and edit Parameters in Houdini with Python: https://gfxhacks.com/create-parameters-in-houdini-with-python

queryEditParameters.py

# edit a parameter using replace
oldParm = "oldParmId"
newParm = hou.FloatParmTemplate("newParmId", "NewParmLabel", 3, default_value=[1, 1, 1])

g.replace(oldParm, newParm)

# if you defined a parameter earlier
g.remove(p)

# ...otherwise remove by id - useful to remove existing parameters
g.remove("myParm")

# clear all custom parameters
g.clear()

# check if a parameter exists. Returns the parameter, else nothing.
g.find("myParm")

# find index of parameter
g.findIndices("myParm")

# if you are using the Python Source Editor
# use print() to print out to the Python Shell
parm = g.find("parm1")
print("{}: {}".format(parm.name(), parm))

# insert parameter above or below another parameter (by ID)
g.insertAfter("id")
g.insertBefore("id")

# insert parameter above or below another parameter or folder (by Index)
g.insertBefore((index,), p)
g.insertAfter((index,), p)

# insert parameter above a parameter within a folder (by Index)
g.insertBefore((folder index, parameter index), p)

# list all parameters in group
l = g.entries()
for i in l:
	print(i)

# list names of all parameters in group
l = g.entries()
for i in l:
	print(i.name)

# list names of parameters excluding folders
l = g.entriesWithoutFolders()
for i in l:
	print(i.name())