By Sagar Shankaran, Founder of CallSphere
GraphRAG moved from research to production in 2026. Three implementations side-by-side: Neo4j-based, Microsoft GraphRAG, and Graphiti's temporal graph approach.
Key takeaways
Vector RAG retrieves chunks. The chunks may or may not capture the entities and relationships a question actually depends on. GraphRAG builds a knowledge graph of the corpus and retrieves subgraphs — entities plus their connections — instead of raw chunks.
For multi-hop questions ("which products did the customers who churned in March also buy?") and questions about relationships, GraphRAG outperforms vector RAG by 10-30 percentage points on standard benchmarks. By 2026 three production implementations dominate.
flowchart TB
Neo[Neo4j-based<br/>LangChain + LlamaIndex] --> StableProd[Strength: maturity, ecosystem]
MS[Microsoft GraphRAG<br/>Open-source] --> Comm[Strength: community-detection, summarization]
Graphiti[Graphiti<br/>Zep] --> Temp[Strength: temporal awareness]
The most common path in 2026. Neo4j as the graph store, LangChain or LlamaIndex as the orchestration layer. Mature, well-documented, deep partner ecosystem (vector indexes inside Neo4j, Cypher generation from LLMs, etc.).
Microsoft Research's open-source pipeline. Distinctive feature: it runs hierarchical community detection on the graph and generates per-community summaries. Queries that span the corpus get answered against community summaries; precise queries get answered against subgraphs.
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Zep's open-source temporal-aware GraphRAG. Tracks bi-temporal facts — what was true, when it was true, when we learned about it — making it especially good for memory and conversational systems.
sequenceDiagram
participant Doc as Source Document
participant LLM as Extractor LLM
participant Graph as Graph Store
participant Comm as Community Detector
Doc->>LLM: extract entities + relationships
LLM-->>Graph: upsert entities + edges
Graph->>Comm: cluster (Microsoft GraphRAG)
Comm->>Graph: write community summaries
All three use an LLM to extract entities and relationships from raw text. They differ in:
A precise question retrieves the subgraph around the mentioned entities and feeds it to the LLM. All three handle this well.
A broad question ("what are the main themes in this corpus?") retrieves community summaries, not subgraphs. Microsoft GraphRAG is purpose-built for this; the others can be adapted with extra work.
"What did the customer prefer six months ago?" Graphiti handles this natively; Neo4j and Microsoft GraphRAG require explicit time properties on edges.
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GraphRAG is more expensive at indexing time than vector RAG — you make a lot of LLM calls to extract entities and relationships. Typical cost is 5-20x vector RAG indexing cost.
At query time it is comparable or cheaper than vector RAG, because you retrieve focused subgraphs instead of large chunk lists.
For corpora that change rarely, the indexing premium pays back. For high-velocity corpora, the index cost can dominate.
flowchart TD
Q1{Need to answer<br/>whole-corpus questions?} -->|Yes| MSc[Microsoft GraphRAG]
Q1 -->|No| Q2{Need temporal<br/>fact tracking?}
Q2 -->|Yes| Gc[Graphiti]
Q2 -->|No| Neo4jc[Neo4j-based]
For most enterprises in 2026, Neo4j-based is the right default. Microsoft GraphRAG when broad-corpus reasoning is core. Graphiti when memory or temporal context dominates.
The pattern in production: vector RAG for chunk-level recall, GraphRAG for entity-level reasoning, fused at query time. Neither alone wins; the combination outperforms either by 5-15 percent on most enterprise benchmarks.

Written by
Sagar Shankaran· Founder, CallSphere
LinkedInSagar Shankaran is the founder of CallSphere, where he builds production AI voice and chat agents deployed across healthcare, hospitality, real estate, and home services. He writes about agentic AI, LLM engineering, and shipping voice agents that handle real calls in production.
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