"Free Network Graph Visualization Tools (No Account Required)" matching MCP servers:

Enables creating interactive data visualizations from natural language queries using DuckDB for local databases or Databricks for enterprise data warehouses. Supports multiple chart types, CSV imports, SQL queries, and automatic statistical analysis through Claude Desktop.

Provides AI agents with a headless personal accounting system via REST API and MCP stdio, enabling account management, transaction recording, transfers, and reporting without a GUI.

Maps Salesforce metadata into a Neo4j graph database, enabling AI agents to reason about schema and generate accurate SOQL queries.

Lets Claude or any MCP client query a Neo4j index of a markdown vault, answering what is connected to a note and how far, how two notes relate, which notes are orphans or dangling links, and running read-only Cypher.

Enables agents to route spoken requests to the right project on the right machine and to remember the outcome by reading and writing a FalkorDB graph, so learned aliases, clarification answers, and episodes carry over across sessions. Exposes five fixed, validated graph tools — route_request, whats_running, machine_blast_radius, project_history, and why_heard — each answering with its MATCH path, Cypher, and parameters, and reporting not-in-graph or ambiguous names distinctly instead of guessing.

MCP server for querying the SEC Ownership Graph, providing curated read-only tools to analyze activist campaigns, control chains, and board interlocks from SEC filings. Answers cite accession numbers and abstain when data is insufficient.

An MCP server for HF radio propagation analytics using the IONIS dataset collection, enabling natural language queries about band conditions, propagation paths, and solar correlations.

Connects to an embedded Kuzu graph database and provides read-only MCP tools for AI clients to query a knowledge graph.

An embedded knowledge graph in one SQLite file, exposing a MCP server for agents to read and write entities and relationships with full audit trail and time travel.

A reference MCP server that connects any MCP client to a free cloud database, supporting 15 database engines with unified tools for querying, storing, listing tables, and annotating tables.

A persistent memory server that implements a local knowledge graph using the Kuzu embedded database to store entities, relationships, and observations. It enables AI models to maintain structured long-term context through searchable nodes and comprehensive tag-based organization.

Builds rich code graphs from TypeScript/NestJS codebases using AST analysis and Neo4j, enabling semantic search, natural language querying, and intelligent graph traversal to provide deep contextual understanding of code relationships and dependencies.

Serves a metadata and lineage graph built from dbt artifacts, letting agents query lineage-aware warehouse context. It also compiles a single policies.yml into database access controls such as Postgres RLS and Unity Catalog.

Enables coding agents to query a temporal knowledge graph derived from a beads issue tracker via read-only Cypher queries, exposing current rules, supersession chains, and provenance without LLM API keys.

Builds and manages a cardiology-focused knowledge graph in Neo4j by extracting medical entities and relationships from documents using LLMs. It enables users to ingest PDFs, refine extracted data, and perform natural language queries to gain clinical insights.

Security Graph MCP Server

An MCP server that provides tools to query and analyze an employee knowledge graph in Neo4j, including semantic resume search, person similarity, and read-only Cypher queries.

MCP data connector for Jazz v2 alpha servers, providing schema discovery and query/read tools with optional mutation capabilities for application data.

A basic implementation of persistent memory using a local knowledge graph. This lets Claude remember information about the user across chats.

Enables AI agents to format SQL, explain queries in plain English, analyze schemas, build queries from natural language, and generate migrations, all without requiring a database connection.

Exposes SQL Server and Snowflake schema metadata to AI coding agents, enabling schema search, join path discovery, and stored procedure metadata retrieval without live queries.

A SQL Server CLI and MCP server for Claude Code that supports standard SQL Server authentication for database interaction and management. It enables users to perform schema exploration, execute queries, and manage data records with built-in SQL injection prevention.

Enables AI assistants to search YouTube videos using the official YouTube Data API v3, extract full video transcripts in multiple languages, and store/retrieve video summaries using a local database.

Provides a scalable knowledge graph implementation for Model Context Protocol using Elasticsearch, enabling AI models to store and query information with advanced search capabilities, memory-like behavior, and multi-zone architecture.

Read-only MCP tools for TROCCO API, enabling workflow and BigQuery datamart audit information retrieval.

MCP server that allows Claude AI to interact directly with MySQL databases, enabling query execution and table information retrieval through natural language.

An MCP server that connects AI assistants to a Neo4j graph database, enabling querying of movie data through tools like graph statistics, genre-based search, and movie details, along with advanced features such as LLM sampling and completions.

Provides comprehensive SQLite database operations for LLMs with security features, transaction support, and separation of read-only and destructive operations.

Database schema management MCP server for Claude Code, enabling natural language management from business requirements to complete databases.

MCP server for snowflake that doesn't allow write operations under any circumstances, and includes a system prompt.

A governed MCP server enabling LLM agents to query BigQuery, inspect GCS, trigger Airflow DAGs, and run data-quality checks with built-in security guardrails like allow-lists, cost ceilings, and audit trails.

Enables database schema querying and execution plan analysis for Spring Boot projects. Supports multiple databases including MySQL, PostgreSQL, MSSQL, and SQLite.

Enables Claude to automatically extract entities and relationships from URLs, PDFs, and YouTube videos to build structured knowledge graphs in Neo4j. It supports custom schemas, academic citation extraction, and community detection for advanced research and content analysis.

An MCP server that equips AI agents with real-world tools including file operations, read-only MySQL queries, web summarization, safe calculations, and system info. It uses stdio transport and enforces safety guardrails like SELECT-only database access and AST-based math evaluation.

A portfolio MCP server demonstrating four tools (web search, database query, file reading, directory listing) with read-only SQL, filesystem sandbox, and both stdio and HTTP transports.

Provides safe, configurable SQL database access via MCP tools, enabling schema introspection, predefined queries, and structured updates with multi-backend support.

A TypeScript MCP server for managing persistent knowledge graphs with entities, directional relations, and time-based observations. It enables users to create, search, and track structured information with built-in concurrency control and JSON file storage.

Enables to interact with Tsurugi RDBMS by executing SQL (DDL, DML, SELECT) and retrieving metadata through MCP.

A read-only MCP server providing SQLite querying, port checking, and git diff summary tools for local development.

Enables read-only queries against a GCP PostgreSQL database, exposing tools to fetch recent users, user details by ID, and recent user activities without returning password or hash columns.