Observe pairs two streams: the outcomes an agent produced (merged PRs, reviews, and negatively, reverts) and the cost it incurred (LLM & tool calls). The value score weighs shipped work against spend so you can compare agents fairly and see which ones earn their cost. The richer your connected sources, the sharper the score.
How scoring works: value against spend
Yardstick ranks agents on the value they created versus what they cost.