CrateDB MCP Server: Frequently Asked Questions

Q: What is the CrateDB MCP Server?

A: The CrateDB MCP Server is a tool that allows Large Language Models (LLMs) like Claude and ChatGPT to directly interact with your CrateDB database. It uses the Model Context Protocol (MCP) to provide context to the LLMs, enabling them to query data, retrieve documentation, and perform other tasks.

Q: What is MCP (Model Context Protocol)?

A: MCP is an open protocol that standardizes how applications provide context to LLMs. It allows LLMs to access and use external data sources and tools.

Q: What are the main use cases for the CrateDB MCP Server?

A: Some key use cases include:

• Translating natural language questions into SQL queries (Text-to-SQL).
• Retrieving CrateDB documentation for accurate information.
• Optimizing and debugging SQL queries.
• Analyzing data and generating visualizations.
• Understanding the current state of your database.

Q: How do I install the CrateDB MCP Server?

A: You can install it using uv tool install: uv tool install --upgrade git+https://github.com/crate/cratedb-mcp

Q: How do I configure the CrateDB MCP Server?

A: You need to set the CRATEDB_MCP_HTTP_URL environment variable to point to your CrateDB instance (e.g., http://localhost:4200/). You may also want to configure the CRATEDB_MCP_DOCS_CACHE_TTL for documentation caching.

Q: Which LLM clients are compatible with the CrateDB MCP Server?

A: Any LLM client that supports the Model Context Protocol (MCP) can be used. Notable examples include Claude Desktop, ChatGPT desktop, OpenAI Agents SDK, and Cursor.

Q: Is it safe to allow LLMs to modify data in my CrateDB database?

A: It’s generally not recommended to allow LLMs to directly insert or modify data. The CrateDB MCP Server defaults to only allowing SELECT statements for security reasons. Carefully consider the risks before enabling data modification capabilities.

Q: How does the CrateDB MCP Server improve query optimization?

A: The MCP server enables LLMs to access database statistics, execution plans, and CrateDB documentation. This allows the LLM to analyze queries and suggest improvements based on best practices and the specific characteristics of your data.

Q: What is the CRATEDB_MCP_DOCS_CACHE_TTL environment variable for?

A: It defines the cache lifetime (in seconds) for documentation resources. The default value is 3600 seconds (1 hour).

Q: What transport options are supported by the CrateDB MCP Server?

A: The server supports both stdio and sse transport methods. You can specify the transport method using the CRATEDB_MCP_TRANSPORT environment variable.

Q: Can I use the CrateDB MCP Server with CrateDB Cloud?

A: Yes, you can. Set the CRATEDB_MCP_HTTP_URL environment variable to the URL of your CrateDB Cloud instance, including the necessary credentials (e.g., https://admin:dZ...6LqB@testdrive.eks1.eu-west-1.aws.cratedb.net:4200/).