Episodes from AI Engineer about GraphRAG.

Citation Needed: Provenance for LLM-Built Knowledge Graphs — Daniel Chalef, Zep AI
Jul 23, 2026 · 20:54
Daniel Chalef argues that provenance for knowledge graphs built by LLMs must itself be a graph, not a simple source ID, because LLM synthesis destroys the paper trail. In Graphiti, the open-source temporal graph framework behind Zep, sources become episodes and derived facts link back to them, enabling a graph walk to trace any fact. This handles merges (merged entities keep all source links), invalidation (invalid-at dates on mutated edges), and metadata projection (tags on episodes inherit to derived facts). Deletion follows the same edges: a fact survives GDPR erasure only if other supporting episodes remain. Benefits include compliance, veracity evaluation, and debuggability for agentic systems.

Your Moat Is Your Data Model — Mike Phipps, Gates Foundation
Jul 22, 2026 · 20:30
Mike Phipps of the Gates Foundation argues that as AI commoditizes frontends and agent frameworks, the durable moat is your data model and the tacit knowledge of how your questions are answered. At the foundation, he and his team modeled 25 years of grantmaking—$7 billion a year across 2,000 grants and 4,000 people—into a single Neo4j knowledge graph served to Claude through one MCP server. The graph is built for agents, not dashboards: hierarchies become traversable paths, and unstructured documents are chunked, tagged, and mapped to structured entities at ingestion. Phipps details the curation pipeline, engaging data owners to capture reporting conventions and safeguard constraints, and explains how the graph connects siloed systems (funding, management, org charts) with unstructured meeting documents. Retrieval evals with LLM-as-judge measure pass-at-one and stability, surfacing gaps that feed back into the data model. The talk makes the case that a small team's efforts compound in the data layer, not the layers above it, offering a practical architecture for enterprise agentic retrieval.

CrabRAG: Why Automated Assistants Need Graph Memory, Not More Tokens — Stephen Chin, Neo4j
Jul 22, 2026 · 20:42
Stephen Chin of Neo4j introduces CrabRAG, a graph-based memory system that outperforms vector databases for AI agent reasoning. He demonstrates that markdown-based memory wastes over 100,000 tokens per round and that vector similarity fails at multi-hop questions. Using a home lab digital twin, he shows a graph agent correctly identifies his daughter's Minecraft server running outdated OS and exposed management ports, while the vector agent returns vague answers. Chin explains that graphs store relationships and enable precise, explainable, and auditable results, and that Claude can write Cypher queries for graph traversal. He announces his book 'GraphRAG: The Definitive Guide' and free training at Neo4j's Graph Academy.

A Practitioner's Guide to Graphs - Tim Ainge, Good Collective
Jul 18, 2026 · 14:18
Tim Ainge from Good Collective presents a practitioner's guide to graphs, covering extraction from unstructured text, schema-first design, and graph-native algorithms to make AI applications smarter, cheaper, and more reliable. He demonstrates that giving extractors a schema (e.g., recipe with ingredients and steps) yields more meaningful graphs, and using ontology instructions standardizes units and ingredient names. Embedding models solve the potato–potato problem by flexibly matching duplicate nodes. Personalized PageRank, inspired by Pinterest's Pixie paper and HIPORAG, finds authoritative nodes in dense graphs, e.g., identifying Miranda v. Arizona as a landmark case not directly cited. Shortest path algorithms reduce tool calls by 40% in code search by retrieving intermediate nodes missed by vector search. Subgraph matching detects software design patterns like the decorator by querying graph shape without specific node details.

Stop AI Agent Hallucinations: 5 Techniques + Production Patterns - Elizabeth Fuentes, AWS
Jul 11, 2026 · 55:19
Elizabeth Fuentes (AWS) presents five code-based techniques to stop AI agent hallucinations, each with measurable before/after metrics. Semantic Tool Selection filters 29 tools to the 3 most relevant per query, cutting token usage from thousands to under 300 per call. Graph-RAG replaces vector similarity with structured graph queries (using Neo4j), enabling precise aggregation and multi-hop reasoning that vanilla RAG fabricates. Multi-Agent Validation uses an Executor-Validator-Critic swarm to catch fabrications, achieving a 92% detection rate. Neurosymbolic Guardrails enforce business rules in Python hooks that the agent cannot skip, achieving zero rule violations. Agent Steering guides agents to self-correct when soft rules fire, completing tasks without hard failures—demonstrated by booking 50 guests by intelligently splitting into two rooms.

Layering every technique in RAG, one query at a time - David Karam, Pi Labs (fmr. Google Search)
Jul 29, 2025 · 20:22
David Karam of Pi Labs (formerly Google Search) walks through layering every technique in RAG, from in-memory retrieval to planet-scale search with 70+ corpus mix of token, embeddings, and knowledge graphs, jointly retrieved and re-ranked at 160,000 queries per second in under 200msec. He advocates a Quality Engineering Loop: baseline with simplest methods, analyze losses, then apply incremental techniques based on complexity-adjusted impact. Karam explains why queries like "falafel" are notoriously hard due to ambiguous intent, highlights failures of chunking documents, and shows when BM25 suffices, when relevance embeddings are needed, and when custom embeddings or domain-specific signals (price, popularity, user clicks) become essential. He covers query orchestration via fan-out, supplementary retrieval across back ends, and distillation for cost optimization, concluding that at sufficient complexity, problems must be punted to LLM or UX for graceful degradation.
Powered by PodHood