What problem does it solve? LLM API spend grows silently as AI features ship, and most teams lack visibility into which endpoints, models, or prompts drive the bill. This Skill audits per-request costs, identifies the 20% of traffic causing 80% of spend, and applies proven techniques to cut costs by 40-80% without degrading output quality. ## Core Features & Use Cases - Cost Audit & Instrumentation: Designs per-request logging schemas (model, tokens, latency, cost per feature) so you can see exactly where money goes before optimizing. - Model Routing & Tiering: Classifies requests by complexity and routes simple tasks to cheaper models, mid-tier tasks to mid models, and only complex reasoning to frontier models. - Caching & Compression: Implements prompt caching for static system prompts, semantic caching for repeated queries, and prompt compression to strip token-wasting filler. - Use Case: Your AI chatbot feature costs $8,000/month and every request hits the largest model with a 3,000-token system prompt. This Skill flags the caching opportunity, designs a routing layer, and projects savings per fix. ## Quick Start Ask the assistant to audit your LLM API costs and identify which endpoints and models are driving the most spend.