SF's AI market segments into LLM applications, computer vision, ML infrastructure, and AI-native product development. LLM application development: the largest and most active segment. Applications: RAG (Retrieval-Augmented Generation) systems (connecting LLMs to proprietary data — knowledge bases, documentation, databases — enabling AI that answers questions about a company's specific information rather than general knowledge), AI agents (autonomous AI systems that can plan, use tools, and execute multi-step tasks — from customer support agents to coding assistants to sales AI), LLM evaluation and observability (measuring LLM performance, detecting hallucinations, monitoring quality in production — tools like Braintrust, Langsmith, and Patronus AI address this need), fine-tuning and customisation (adapting base models to specific domains and tasks — fine-tuning Llama, Mistral, or GPT-4 on domain-specific data to improve accuracy and reduce costs), and multi-model orchestration (routing queries to different models based on complexity, cost, and quality requirements — Claude for reasoning, GPT-4o for speed, open-source for cost-sensitive tasks). Computer vision: SF and the Bay Area host the world's densest CV ecosystem. Applications: autonomous vehicle perception (detecting pedestrians, vehicles, cyclists, and road infrastructure from camera, lidar, and radar data — Waymo, Cruise, Zoox, and dozens of companies), robotics vision (warehouse automation, manufacturing inspection, and general-purpose robot perception — companies like Figure AI and Covariant build in the Bay Area), medical imaging (radiology, pathology, and dermatology AI — several SF startups build diagnostic AI), satellite and aerial imagery (agriculture, real estate, infrastructure monitoring from satellite data — Planet Labs and other space companies), and generative computer vision (image generation, video synthesis, 3D scene generation — the latest frontier in CV research). ML infrastructure: SF companies build and need infrastructure for AI. Applications: model training platforms (distributed training across GPU clusters — orchestration, checkpointing, data loading, and experiment tracking), inference infrastructure (deploying models efficiently — model serving, GPU allocation, batching, and autoscaling), data labelling and curation (preparing training data — annotation tools, data quality measurement, and synthetic data generation), ML monitoring (detecting model degradation, data drift, and performance issues in production), and cost optimisation (GPU costs are the dominant AI expense — infrastructure that minimises cost per token, cost per inference, or cost per training run). AI-native products: SF startups where AI is the product. Categories: AI coding (Cursor, GitHub Copilot, Replit), AI search (Perplexity, You.com), AI sales (11x, Artisan), AI customer support (Sierra, Intercom), AI legal (Harvey, Casetext), and AI healthcare (various).