Overview

An AI model does not need retrieval for every question. The important problem is knowing when its internal knowledge is no longer enough. The Retrieval Trigger is a practical decision boundary that determines when an AI system should stop relying solely on model knowledge and obtain external evidence before answering.

An LLM does not magically know your files, databases or APIs. This practical continuation of the RAG series shows, with simple Python, how external data becomes retrievable evidence: from text files and SQL to full-text search, embeddings, context assembly and the final LLM call.

OpenAI’s agent stack changed in September 2026. This architecture guide separates the Agents API, Agents SDK, Responses API, and Codex SDK by runtime ownership—so teams can choose the right control boundary instead of comparing product names.

Loving Rocks is an enterprise-grade wedding platform designed with a true multi-tenant architecture, isolated databases per tenant, and built-in internationalization for global scalability, security, and long-term operational stability.