4. Child-Thread Spawn
A runtime affordance that creates a new execution unit with its OWN fresh context window. Returns a value to the parent. Multiple may run in parallel.
INDUSTRY TERMS: “subagent thread”, “Task tool”, “background agent”.
WHEN TO USE: any work that benefits from CONTEXT ISOLATION — a fresh window where a specialized lens (its own persona, its own rule set, its own loaded assets) sits at full attention rather than competing with the parent’s session for tokens.
KEY PROPERTY: stateless across spawns. Anything not loaded as text into the child thread does not exist for that thread. Hand off via explicit artifacts, not assumed memory.
Compounding gain
Section titled “Compounding gain”A MODULE ENTRYPOINT that is dispatched in a fresh child thread converts a Separation-of-Concerns win into a context-isolation win for free. This is the core argument for splitting a god-module into specialized siblings — each split unlocks an independently spawnable thread.
See also
Section titled “See also”- Module Entrypoint — what runs inside the spawned thread.
- Persona Scoping File — loaded into the spawn at startup.
- Plan Persistence — the only safe handoff channel between parent and spawn.