Fable 5 Rule 3: Freeze Prefixes to Save on Cache Costs
thisdudelikesAI · x · 2026-07-03
The author recommends placing system prompts and stable project context byte-by-byte at the very beginning, keeping them consistent across turns, while putting changing content at the end. This is the key to making prompt caching genuinely cost-effective against Fable 5's relatively high token costs.
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