Harness Levers

Each project changes one lever. Keep the task stable, change the harness, then inspect whether behavior improves.

The Levers

Lever	Question	Project
Trace	Can you explain what happened?	P01
Model	Did the task need the expensive model?	P02
Retrieval	Did extra search improve the answer?	P03
Decomposition	Did smaller prompts beat one large prompt?	P04
Memory	Did durable context reduce re-discovery?	P05
Safety	Did the harness bound the blast radius?	P06
Critic	Did evaluation stop false completion?	P07
Workflow	Did model-authored orchestration reduce glue code?	P08
Escalation	Did routing recover when cheap got stuck?	P09
History	Did indexing past sessions beat scanning them?	P10

The Rule

Excessive harness features can lead to bloat. Use traces and metrics to ensure your harness is optimized for your work.

That is why the course teaches: predict, run, inspect, measure, keep.