Skip to content
Genkit

Neo4j plugin

The Neo4j plugin provides indexer and retriever implementations that use the Neo4j graph database for vector search capabilities.

Installation

Terminal window
npm install genkitx-neo4j

Configuration

To use this plugin, specify it when you initialize Genkit:

import { genkit } from 'genkit';
import { neo4j } from 'genkitx-neo4j';
import { textEmbedding004 } from 'genkitx-googleai';


const ai = genkit({
  plugins: [
    neo4j([
      {
        indexId: 'bob-facts',
        embedder: textEmbedding004,
      },
    ]),
  ],
});

You must specify a Neo4j index ID and the embedding model you want to use.

Connection Configuration

There are two ways to configure the Neo4j connection:

  1. Using environment variables:
NEO4J_URI=bolt://localhost:7687  # Neo4j's binary protocol
NEO4J_USERNAME=neo4j
NEO4J_PASSWORD=password
NEO4J_DATABASE=neo4j  # Optional: specify database name
  1. Using the clientParams option:
neo4j([
  {
    indexId: 'bob-facts',
    embedder: textEmbedding004,
    clientParams: {
      url: 'bolt://localhost:7687',  // Neo4j's binary protocol
      username: 'neo4j',
      password: 'password',
      database: 'neo4j', // Optional
    },
  },
]),

Note: The bolt:// protocol is Neo4j’s proprietary binary protocol designed for efficient client-server communication.

Configuration Options

The Neo4j plugin accepts the following configuration options:

  • indexId: (required) The name of the index to use in Neo4j
  • embedder: (required) The embedding model to use
  • clientParams: (optional) Neo4j connection configuration

Usage

Import retriever and indexer references like so:

import { neo4jRetrieverRef } from 'genkitx-neo4j';
import { neo4jIndexerRef } from 'genkitx-neo4j';

Retrieval

Use the retriever reference with ai.retrieve():

// To use the index you configured when you loaded the plugin:
let docs = await ai.retrieve({
  retriever: neo4jRetrieverRef,
  query,
  // Optional: limit number of results (max 1000)
  k: 5
});


// To specify an index:
export const bobFactsRetriever = neo4jRetrieverRef({
  indexId: 'bob-facts',
  // Optional: custom display name
  displayName: 'Bob Facts Database'
});
docs = await ai.retrieve({
  retriever: bobFactsRetriever,
  query,
  k: 10
});

Indexing

Use the indexer reference with ai.index():

// To use the index you configured when you loaded the plugin:
await ai.index({ indexer: neo4jIndexerRef, documents });


// To specify an index:
export const bobFactsIndexer = neo4jIndexerRef({
  indexId: 'bob-facts',
  // Optional: custom display name
  displayName: 'Bob Facts Database'
});
await ai.index({ indexer: bobFactsIndexer, documents });

See the Retrieval-augmented generation page for a general discussion on indexers and retrievers.

Learn More

For more information, feedback, or to report issues, visit the Neo4j plugin GitHub repository.