Self-Extending Agents

Three escalating levels of agent-authored code, from ephemeral to persistent:

Level	Mechanism	Lifetime	Give the agent
In-cell helpers	plain `def` in a CodeAct cell	REPL locals, gone after the call	`MethodWriting` skill (guidance only)
LLM-powered sub-calls	standalone `@strategy` functions in a cell	same cell scope	`MethodWriting`
Persistent libraries	Python packages under a `libs/` dir	on disk, hot-reloaded, across sessions	`SkillWriting` (`self.libs`)

In-cell helpers and standalone sub-calls (`MethodWriting`)

MethodWriting (nooa.tools.method_writing_lib) is a guidance Skill — attach it and the LLM learns to:

define plain helpers at the top of a cell for deterministic logic, then use them;
define standalone generation functions for per-item LLM sub-tasks and fan them out: