Aworkflow costing $0.50 per LLM-in-the-loop execution becomes $50,000 a month at scale. That math is why a quiet architectural pattern keeps surfacing: let the agent reason through a workflow once, compile that reasoning into deterministic Playwright code, then replay the script on every subsequent run. Think expensive thoughts exactly once.
Skyvern's implementation offers the clearest public numbers. Their explore-then-replay model cuts per-run costs from $0.11 to $0.04 and execution time from 279 seconds to 120. The runs become deterministic. What makes the pattern durable is intent metadata captured during exploration, so when a site inevitably changes, the system heals using semantic understanding rather than brittle CSS selectors.
The deeper idea here resembles institutional memory. A senior employee learns a process, writes it down, and the next person follows the notes. The LLM's initial exploration is the learning. The compiled code is the documentation. And like good institutional knowledge, it degrades gracefully: when the notes no longer match reality, the system knows enough about the original intent to adapt rather than fail silently.