Azure AI Services

Microsoft's AI stack on Azure spans three layers: Azure OpenAI Service for direct access to OpenAI models, Azure AI Foundry for multi-model generative AI with agents and evaluation, and Azure Machine Learning for classical ML training and MLOps. Task-specific services (Document Intelligence, AI Search, AI Vision, AI Language) round out the platform.

Generative AI

Azure OpenAI Service GPT-4o, o1, o3-mini, DALL·E 3, Whisper — with Entra ID auth, content filtering, and On-Your-Data RAG.

Azure AI Foundry Multi-model catalog, Agent Service, Prompt Flow, evaluation, and safety in one workspace.

Azure Machine Learning Training, AutoML, hyperparameter sweeps, managed endpoints, MLOps pipelines.

Retrieval & Document AI

Azure AI Search Hybrid (BM25 + vector) search with semantic reranking — the default RAG retriever on Azure.

AI Document Intelligence OCR, forms, tables, invoices, IDs, contracts — Markdown output for LLM ingestion.

AI Vision & Language Image analysis, multimodal embeddings, sentiment, NER, PII redaction, summarization.

Choosing Between Azure AI Services

Just need GPT-4o / o1 / embeddings? → Azure OpenAI Service.
Building a generative app with agents, evaluation, multiple models? → Azure AI Foundry.
Training a custom classical model (XGBoost, PyTorch) or running MLOps pipelines? → Azure Machine Learning.
Extracting structured fields from PDFs / forms? → Document Intelligence.
RAG retrieval over enterprise documents? → Azure AI Search (with Document Intelligence for parsing).
Well-defined NLP task (sentiment, NER, PII)? → Azure AI Language — faster and cheaper than GPT.
Image understanding or multimodal search? → Azure AI Vision.

Azure vs. AWS Equivalents

Azure	AWS Equivalent	Notes
Azure OpenAI Service	Amazon Bedrock	Azure hosts OpenAI; Bedrock hosts Anthropic/Meta/Mistral/Cohere/Amazon (not OpenAI).
Azure AI Foundry	Bedrock + SageMaker Studio	Foundry unifies model catalog + agents + evaluation.
Azure Machine Learning	Amazon SageMaker	Closest peers — full ML platform.
Azure AI Search	Amazon OpenSearch + Kendra	AI Search's semantic reranker has no direct AWS equivalent.
AI Document Intelligence	Amazon Textract	Similar features; Document Intelligence emits Markdown natively.
Azure AI Vision	Amazon Rekognition	Florence-backed; Rekognition stronger on video/faces.
Azure AI Language	Amazon Comprehend	Similar NLP primitives; Azure bundles QnA + CLU.