---
id: ai-rag-corpus
area: ai
level: 3
title: "Artefact — Retrieval corpus and query graph"
claim: "Retrieval is filtered by metadata before it searches — a tagged corpus · a four-node LangGraph query graph · and a deliberate replacement of ChromaDB with Qdrant."
confidence: running
period: "2020–"
tech: [Qdrant, LangGraph, Prefect, n8n, ChromaDB]
metrics: [{label: "retrieval stores used over time", value: 2}]
artefacts: []
public: true
last_verified: 2026-10-26
tags: [ai, retrieval, rag, artefact]
---

The query graph diagram and an ingest run log land later; this site's own corpus build is Phase 4.

## What the artefact is

The ingest and query path: documents are chunked and tagged with metadata at ingest, stored in Qdrant, and filtered on that metadata before a similarity search runs. The LangGraph graph has four nodes; the fourth decides whether the answer can be given from what was retrieved.

## What it proves

Retrieval designed around payload filtering and a hard stop, plus the reasoning for moving off ChromaDB — heavier footprint and weaker filtering — recorded as a decision rather than a migration.

## When it is delivered

The query graph diagram in Phase 7. The live demonstration of the same pattern is this site's own retrieval, delivered in Phase 4 and Phase 5.