What Is a Recursive Language Model?

Alex Zhang says a recursive language model, an RLM, is a harness whose only tool is code. He wishes that definition had been in the original paper. The code can call the model again as a tool, and the other tools are functions in that same code. The context stays in memory inside the code environment, which can be a file system. In Prime Agent, the trajectory stays on disk even after compaction, so the model can still read the original context, and the tools run in a Python REPL or a Bash REPL. He calls that a primitive abstraction.

Most harnesses differ on that point. Context offloading is not done that way, so the working context does not stay in the code environment the way an RLM keeps it.