MCP Directory

MCP servers for vector & semantic search

Store and query embeddings for RAG and long-term agent memory.

4 servers · Last updated June 17, 2026

TL;DR: These servers give your agent a vector store — upserting embeddings and running similarity search for RAG and persistent memory. They differ on whether they're a dedicated vector DB, a general database with vector support, or an in-process memory store. This is the retrieval half of any RAG stack.

Bottom line: if you only try one, Memory (Knowledge Graph) is the most popular, verified option for this (74,000★). 3 more compared below.

Compare 4 servers

ServerTransportAuthVerifiedStarsTools for this
Memory (Knowledge Graph)Local (stdio)No auth74,000create_entities, delete_entities, read_graph +2
Qdrant MCP ServerLocal (stdio)API key1,100qdrant-store, qdrant-find
Chroma MCP ServerLocal (stdio)API key600chroma_list_collections, chroma_create_collection, chroma_peek_collection +4
Pinecone Developer MCP ServerLocal (stdio)API key500upsert-records, search-records

The servers

Official MCP server providing persistent, file-backed knowledge-graph memory across sessions.

create_entitiesdelete_entitiesread_graphsearch_nodesopen_nodes

Official Qdrant server using a vector collection as semantic memory: store and find embeddings.

qdrant-storeqdrant-find

Official Chroma server: create collections and run vector, full-text, and metadata search.

chroma_list_collectionschroma_create_collectionchroma_peek_collectionchroma_get_collection_infochroma_get_collection_countchroma_modify_collection

Official Pinecone server: manage indexes, upsert/search records, rerank, and search Pinecone docs.

upsert-recordssearch-records

Use these in a stack

FAQ

Dedicated vector DB vs memory server?

Use a dedicated vector store (Chroma, Qdrant, Pinecone) for scale and persistence; a lightweight memory server is fine for small, single-agent context.

What pairs with a vector server for RAG?

A scraping/search server to gather content and an embeddings step — see the RAG agent stack for a ready-made combination.

Other capabilities