Custom GPT
Unpack how a Custom GPT is configured and where it stops: how instructions, knowledge files and tools combine, why Apps and Actions exclude each other, and the pitfalls around Projects and Code Interpreter.
A Custom GPT is a configurable layer inside ChatGPT: instructions, knowledge files and tools bundled into one shareable assistant that users call from an ordinary chat. Its edges matter in practice — opening a Project conversation with one moves the thread outside the Project, Apps and Actions are mutually exclusive, and without Code Interpreter it cannot hand back a real file.
