---
title: Day 12 of Green, Efficient AI is live — Cache What Doesn't Change.
type: post
date: 2026-06-15
source: linkedin
original_url: "https://www.linkedin.com/feed/update/urn%3Ali%3AugcPost%3A7472172146073522176"
topics: ["green-software", "ai-economics", "agentic-ai"]
summary: Day 12 of Green, Efficient AI is live — Cache What Doesn't Change. Depending on the workload, forty to ninety-five percent of every AI prompt is the same as the last one — the system prompt, the tools, the document the agent is reading. The model reprocesses…
draft: false
---

Day 12 of Green, Efficient AI is live — Cache What Doesn't Change.

Depending on the workload, forty to ninety-five percent of every AI prompt is the same as the last one — the system prompt, the tools, the document the agent is reading. The model reprocesses all of it from scratch, every time, paying the energy bill, the cost bill, and the latency bill twice for an output it already computed once.

The fix is not clever prompting. It is treating the prompt as a data structure with a stable part and a variable part, and telling the system which is which.

The four-rung ladder for fixing it, in today's issue.

Green Software Foundation #greenai #efficentai #aieconomics #leanagenticai