--- title: We Built a Routing Layer to Cut Our AI Costs. It Broke... description: A team built a classifier-based routing layer to cut AI inference costs by routing simple queries to cheaper models, saving ~60% on their monthly bill. Three... canonical: https://daily.dev/posts/we-built-a-routing-layer-to-cut-our-ai-costs-it-broke-the-product--74ka47hyk twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: We Built a Routing Layer to Cut Our AI Costs. It Broke the Product. | daily.dev og:description: A team built a classifier-based routing layer to cut AI inference costs by routing simple queries to cheaper models, saving ~60% on their monthly bill. Three... og:url: https://daily.dev/posts/we-built-a-routing-layer-to-cut-our-ai-costs-it-broke-the-product--74ka47hyk og:image: https://api.daily.dev/og/posts/74kA47hYK.png og:image:alt: We Built a Routing Layer to Cut Our AI Costs. It Broke the Product. og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # We Built a Routing Layer to Cut Our AI Costs. It Broke the Product. **[Towards Data Science](https://daily.dev/sources/tds)** · 20 min read · 1 upvotes · 0 comments ## Summary A team built a classifier-based routing layer to cut AI inference costs by routing simple queries to cheaper models, saving ~60% on their monthly bill. Three months later, customer satisfaction dropped and churn rose — the quality loss cost 4-5x the savings. The root cause: classifiers can't reliably detect 'long-tail' query complexity from surface form, cheap models fail confidently on edge cases, and existing monitoring aggregated quality across tiers, hiding tier-specific degradation. The post details the failure mechanics, a detection methodology (per-tier quality monitoring, long-tail oversampling, classifier confidence drift tracking), and an alternative architecture — uncertainty-routed cascades where every query starts at the cheap model and escalates to the capable model only when confidence is low. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Multi-Model Routing Is an Infrastructure Decision, Not a Feature: The Tradeoffs Nobody Publishes](https://daily.dev/posts/multi-model-routing-is-an-infrastructure-decision-not-a-feature-the-tradeoffs-nobody-publishes-zbm50wrn5) · DigitalOcean Community · 0 upvotes · 0 comments - [How to Build a Cost-Efficient AI Agent with Tiered Model Routing](https://daily.dev/posts/how-to-build-a-cost-efficient-ai-agent-with-tiered-model-routing-zrc6k7gmk) · freeCodeCamp · 1 upvotes · 0 comments - [Cheap AI Models Need Just a 4% Win Rate to Gut Your Frontier Bill](https://daily.dev/posts/cheap-ai-models-need-just-a-4-win-rate-to-gut-your-frontier-bill-7ohuei5km) · Medium · 0 upvotes · 0 comments --- Tags: [#ai-agents](https://daily.dev/tags/ai-agents), [#observability](https://daily.dev/tags/observability) [View this post on daily.dev](https://daily.dev/posts/we-built-a-routing-layer-to-cut-our-ai-costs-it-broke-the-product--74ka47hyk) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"We Built a Routing Layer to Cut Our AI Costs. 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