• Write Python code in a node that executes when the workflow is queued
• The stdout/stderr (e.g., prints, error tracebacks) are displayed in the node.
• The input values can be accessed by their UI name.
• The output values are the same as the input values, changes made to input values in the code are reflected in the output values.

• python 3.10+

1. cd into ComfyUI/custom_nodes directory
2. git clone this repository

• Embedding scripts into workflows
• Specialized tasks
• Converting types
• Doing math
• Debugging
• Testing custom nodes
• Even if you can't code, you can ask ChatGPT to write a python snippet

• The variables in the UI (e.g., image1, number1, text1, etc.) can be accessed directly in the code by the same name

  print(image1.shape)
  print(number1 * random.randint(0, 99))

• The output values share the same names as the input values. Changes you make to these variables will be reflected in the output values.
• The code will work as expected in almost all cases except for i. re-assignment and ii. passing the variables as arguments to functions.
  1. To re-assign a variable, you must use its to() method, regardless of the variable's type

     # Instead of number1 = float(number1):
     number1.to(float(number1))
     
     # Instead of image1 = 0.5 * (image1 + image2):
     image1.to(0.5 * (image1 + image2))
     
     # Instead of mask1 = 1 - mask1:
     mask1.to(1 - mask1)
     
     # Instead of text1 = text1.replace("bad", ""):
     text1.to(text1.replace("bad", ""))
     
     # In-place operators (+=, ++, /=, etc.) will work normally
     number1++
     text1 += " is good"

  2. To pass the variables as arguments to functions, just pass the .data attribute of the variable instead (regardless of the variable's type)

     # Instead of pil_img = ToPILImage()(image1):
     pil_img = ToPILImage()(image1.data)
     
     # Instead of random.sample[number1, number2]:
     random.sample([number1.data, number2.data])
     
     # Not necessary for built-in functions
     print(image1) # works
     print(len(text1)) # works

• To understand the type and shape of some of the inputs, please refer to the Images, Latents, and Masks section of comfydocs.org.
• This situation is unlikely to occur, but try to avoid re-assigning variables to objects of a different type. You may lose access to some instance methods. If it must be done (e.g., to get an ouput of a novel type), just do it at the end of the code, and use your own variables in the meantime.

• Automatically get color palette and complements from image
• Most recent image in folder
• Paste text on image
• ...More snippets in wiki

Disclaimer: Do not put this on a server that is accessible to the public. This node can run any Python code provided by a user, including malicious code.