# Zillow Explains the Risks of Building AI ROI Without Measurement Real-time context layer determines AI success. - **Source:** [VentureBeat](https://venturebeat.com) - **Published:** 2026-07-20 - **Topic:** [Data & AI](https://brifing.si/c/data-ai) - **Original article:** - **On Brifing:** https://brifing.si/s/c24ff62e-88f9-4457-9177-268f3a8f1dbf ## Zillow's AI journey Zillow has come a long way in understanding AI's role in real estate transactions. Tracking customer context emerged as a more challenging problem than raw data. This highlights AI's need to focus on context, not just data. ## Importance of the context layer Zillow developed a context layer that tracks customers' positions in the real estate process. This layer ensures context is maintained as customers transition between platforms. It's a critical step in unlocking AI's true business value. ## Glean's role Zillow automated repetitive tasks by working with Glean. Glean's centralized integration approach streamlined connections for finance, legal, and marketing teams. This increased efficiency while reducing costs. ## Model routing and cost Glean reduced token consumption by routing tasks to smaller, cheaper models. Precomputed context sped up the model's context-building process. This strategy is key to controlling AI costs. ## Importance of metrics Zillow used DORA metrics to measure AI's impact, proving it increased code shipping speed by 40%. Metrics are a fundamental tool for evaluating AI success. ## The future of AI Zillow and Glean's approach offers valuable lessons on implementing AI in enterprise systems. Context management and cost control emerge as critical factors in AI's success. ## Sources covering this story - https://venturebeat.com/data/at-vb-transform-2026-zillows-engineering-chief-said-ai-roi-numbers-only-hold-up-if-you-measure-before-you-build — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._