wtf( )unctionsystem design, drawn
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A one-line prompt change shipped on Friday

Someone tweaked the system prompt to make answers more concise. By Monday the assistant had stopped citing sources and started confidently answering questions outside the knowledge base.

Nothing caught it. The only check before merge is that the service returns 200 — prompts, model versions and retrieval settings are production configuration with no compiler and no tests.

Put the gate in the pipeline that code already has.
Components — tap one, then tap a slot on the diagram
!A one-line prompt change stopped the assistant citing sources. Nothing caught it until Monday.

Outside every boundary: Production (FAILED: regressed), Prompt + config (in git), Golden set (real queries, graded), an empty slot for the before promotion Connections: Prompt + config calls before promotion (step 1) Golden set controls before promotion — expected behaviour (step 2) before promotion calls Production — only if it clears (step 3)

Productionregressed
Prompt + configin git
Golden setreal queries, graded