What is marginal cost per run?
Marginal cost per run is what it costs to execute a workflow one additional time. On infrastructure that re-runs the LLM every execution, that cost is roughly constant no matter how often you run. When repeated and re-phrased runs increasingly resolve through a semantic cache to deterministic replay, the marginal cost trends toward browser time alone.
Why it matters
It is the number that decides whether automating at volume is sustainable. A flat marginal cost means your bill scales linearly with usage; a falling one means cost per 1,000 runs drops as you scale.