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CyrilXBT
How to Build a Coding Agent That Costs 80% Less: Jev + Opus 5.5 (Full Architecture)
How to Build a Coding Agent That Costs 80% Less: Jev + Opus 5.5 (Full Architecture)
Core points (3)
- Frontier models waste tokens deciding between fixed options that a cheap decision model can answer
- The harness, not the model, owns thresholds and always falls back to Opus when unsure
- Measure cost per session before and after — the only number that proves the architecture works
