Nlqueries: MCP server, setup and security

What Nlqueries does

According to its repository: “Self-hosted natural-language-to-SQL engine with validation for PostgreSQL, MySQL, Snowflake, BigQuery and DuckDB, plus document QA and semantic caching.”

An MCP server gives an AI agent extra tools it calls during the conversation: the agent reads their description, decides to use them and gets the result back. Nlqueries is listed under Databases, a category of 138 servers in the directory, where it ranks #134 by stars.

Topics declared by the repository: cli, database, natural-language-to-sql, nl2sql, python, sql.

Installing and connecting Nlqueries

No package or remote server is declared in the official MCP registry: you install it from source, following the repository README.

Like any MCP server, you declare it in your client's configuration (Claude Desktop, Claude Code, Cursor, VS Code, Codex…): a name, the command that starts it or its URL, and any environment variables. The client then starts it and lists its tools. Project language: Python.

Security: what to check

An MCP server runs code with the rights you give it, and the model reads its tool descriptions: a malicious or compromised server can hijack the agent. Read the code, or pick a maintained and widely used server, before connecting it.

Points found for Nlqueries:

• No licence: without a licence the code is not legally reusable, even if it is public. Avoid it in a company setting without the author's agreement.

Good practice: grant only the rights needed (least privilege), require human approval for irreversible actions, and run the AI agent security check.

Project activity and maintenance

Created on June 4, 2026, the nlqueries/nlqueries repository has 5 stars and 0 forks, with 0 open issues. It has more stars than 13% of the servers in the directory. It received changes this month.

Stars measure attention, not quality: a recent, heavily promoted project can collect them fast, while a useful but niche server will have few.