Sub-Agents and Ralph Loops

When a task is big enough, you do what good teams always do: hand a clear brief to a trusted specialist.

That is what sub-agents and Ralph loops are for. Your primary agent stays accountable for the outcome, but it delegates execution to a dedicated session built for deeper work. This is not complexity for its own sake. It is how you avoid trying to force multi-hour implementation through one fragile live chat.

The loop starts with a concrete brief. Not a vague "please fix this," but a scoped task with expected outputs, done criteria, and verification requirements. A strong brief makes restarts survivable because a new session can resume from written intent instead of guessing from partial conversation.

From there, the work runs in isolation and gets tracked while in flight. That tracking matters more than people expect. Long jobs fail quietly when nobody owns state. A status record with start time, target thread, and run state makes monitoring and recovery practical.

Routing is another hard-won lesson. Completion updates should return to the topic where the project lives, not wherever the last message happened. Otherwise teams lose project history and decisions become hard to audit.

The biggest lesson is verification. A confident completion message is not proof of completion. We have seen jobs report success while files were unchanged or outputs never materialized. So "done" requires evidence: expected artifacts exist, checks pass, and visible changes are real.

This is where many teams cut corners under deadline and pay for it later. A five-minute verification pass is cheaper than discovering missing work after handoff.

For staff, the practical takeaway is simple. If your agent says it is writing a brief, launching a dedicated session, and monitoring progress, that is the right behavior. It means the system is treating substantial work with the same discipline you would expect from a strong teammate.