MemGPT is an interesting project which provides GPT agents with unbounded memory. It includes the ability to incorporate custom functions, with a convenient JSON schema generator.

In trying to extend the agent with functions of my own, I found that the agent was reluctant to give me information about the functions I was making available to it, so I wrote a set of meta-functions which enable the agent to view source code, set debugger lines, and create functions. You can view the source code here. Note that running this requires some edits I made to MemGPT to enable dynamic function reloading (PR).