It includes a prompt library and a playground and works with every model backend you set up (I tested a lot with Ollama). You can see screenshots here: https://promptmage.io/getting-started/#flow-playground
Promptmage is a python package meant to support building complex, multi-step llm workflows. Have a look at the examples here to get an idea: https://github.com/tsterbak/promptmage/tree/main/examples