Pattern: Grader Loops — Subagents That Revise Until Output Meets a Rubric

Anthropic·medium signal

The emerging production pattern pairs fan-out subagents with a separate grader that sends each subagent back to revise until its result satisfies a rubric, rather than accepting the first completion. This 'Performance Outcomes' style loop turns probabilistic agent output into something closer to test-gated work. Adversarially verifying or rubric-grading each subagent's result before merging is the reliability lever for large fan-outs.