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Facio's Versioned Prompts: How AI Agent Behavior Stays Reproducible Through Model and Code Changes
Facio's Versioned Prompts: How AI Agent Behavior Stays Reproducible Through Model and Code Changes
An AI agent's behavior comes from the prompt, the model, and the code that interprets both. Change any of them and the behavior changes. The team upgrades the model — the agent's responses shift subtly. The team tweaks the prompt to fix a bug — the fix breaks three other things. The team refactors the agent code — the agent stops working entirely. Reproducibility collapses. Facio's versioned prompts discipline makes agent behavior reproducible: every prompt version is pinned, every change is tracked, every comparison is traceable.