auto-ontology-mcp

auto-ontology-mcp is an MCP server that brings NVIDIA Auto Ontology's semantic layer to Claude, ChatGPT, Codex, Cursor and other MCP clients, so your own model can model a database, answer questions with checked read-only SQL, and keep a personal knowledge base exported to Obsidian.

Why it matters

For analysts and builders who ask AI about their databases or notes: text-to-SQL often returns a wrong number silently, and this server checks joins, stored values and fan-out against a reviewed ontology before a query runs, with no separate model endpoint or API key.

Highlights

• Scans a database through SQLAlchemy, profiles columns and infers undeclared primary and foreign keys, then hands tables to your client's model to name business Terms and review joins.
• validate_sql flags unknown columns, joins the ontology doesn't know, near-miss literals (for example 'pennsylvania' vs 'Pennsylvania'), percent-vs-fraction thresholds and one-to-many fan-out; check_answerable says when the data can't answer a question.
• Connected databases are only read: a SQL guard allows one SELECT or WITH per call, connections open read-only, every transaction is rolled back, and queries time out after 30 seconds with at most 500 rows.
• A knowledge store for receipts, papers and notes keeps records, concepts and passages with their sources, searchable with full-text search; export_wiki writes it out as an Obsidian vault, offered as an alternative to the LLM Wiki pattern.
• Runs over stdio or streamable HTTP, with one-click install links for Cursor and VS Code and config snippets for Claude Code and other clients.

Taken from the project's own README, docs or launch page. Claims about speed or accuracy are the maker's unless stated otherwise.

Worth knowing: A personal project, not affiliated with or endorsed by NVIDIA. Datasource URLs, passwords included, are stored in plain text in ~/.auto-ontology-mcp/ontology.db, so the README advises a read-only database account. Query results are sent to whichever model your MCP client uses.

Quick facts

Links

• Repository: https://github.com/gogoymh/auto-ontology-mcp

Related ranking

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Checked 2026-11-08 from the tool's own pages. Prices and star counts change, so confirm on the official site. Listing here is not a ranking or an endorsement.