"How to Query a Knowledge Graph Using an Ontology" matching MCP servers:

Enables AI agents to query organizational architecture and governance constraints, returning evidence-grounded answers from documented structures.

MCP server for querying versioned C2PA specification knowledge graphs, enabling AI agents to browse entity definitions, validation rules, and version diffs via natural language.

Enables searching Google's Knowledge Graph for real-world entities via two tools: search by query or lookup by Machine ID, returning structured data including entity types, descriptions, and URLs.

Enables building and querying vector-based knowledge graphs with node and edge management and semantic search.

Enables searching and querying Korean law ontology via SPARQL, with tools for law search, detail, agency, region, statistics, and network visualization.

An AI recipe recommendation server based on the MCP protocol, providing functions such as recipe query, classification filtering, intelligent dietary planning, and daily menu recommendation.

Enables AI assistants to query the Ubergraph biomedical ontology SPARQL endpoint with tools for custom SPARQL queries, term lookup, search, and hierarchy traversal.

An MCP server for Dart AI task management that enables bulk operations using DartQL selectors to minimize token usage and context rot. It provides tools for batch updates, task and document CRUD, and safe CSV imports with integrated dry-run capabilities.

Token-efficient Figma MCP server with image export, query DSL, and design token support.

Enables full CRUD control of Ontology items in Microsoft Fabric, including entity types, relationships, data bindings, and workspace discovery through natural language.

Enables AI assistants to search arXiv papers, retrieve metadata, browse categories, and read paper text.

MCP server for running read-only SQL queries across MySQL and PostgreSQL databases with safety guardrails, credentials stored outside source, and support for multiple databases.

Enables querying official Brazilian Central Bank PTAX dollar closing exchange rates by specific date, date range, or most recent available quotation.

An MCP server that enables semantic search over a private knowledge base via pgvector, with GitHub OAuth authentication and a RAG pipeline.

提供A股实时行情、历史K线、财务报表、技术指标等全方位数据查询的MCP服务器，支持盘中即时更新及批量查询。

A versatile tool that enables querying and exporting data from multiple relational databases (MySQL, PostgreSQL, Oracle, SQLite, etc.) in read-only mode for data safety.

An MCP server that connects AI assistants to YNAB budgets, enabling natural language queries about finances backed by full API coverage and built-in YNAB methodology knowledge.

A FastMCP server that enables AI applications to navigate and query OpenAPI specifications, including resolving $ref pointers and inspecting paths and operations.

Enables querying and comparing products from MM's retail (B2C) and wholesale (B2B) platforms in Vietnam, including price comparisons, stock availability checks, and multi-store support with Vietnamese language integration.

This MCP server provides secure access to databases for AI agents, enforcing authentication, authorization, human approval, logging, and notifications to prevent dangerous actions.