--- title: "DuckDB / MotherDuck Local MCP: review, setup & limitations · Undominated.ai" canonical: https://undominated.ai/mcp-servers/motherduck/ description: "Runs analytical SQL against a chosen DuckDB file or MotherDuck connection from a local MCP process." --- # DuckDB / MotherDuck Local MCP: review, setup & limitations · Undominated.ai > Runs analytical SQL against a chosen DuckDB file or MotherDuck connection from a local MCP process. [← Explore all mcp servers](/mcp-servers/) LOCAL ANALYTICS / MotherDuck # DuckDB / MotherDuck Local MCP Runs analytical SQL against a chosen DuckDB file or MotherDuck connection from a local MCP process. See setup guidance ↓Original source ↗ SOURCE REVIEW Reviewed 2026-09-21 Evidence 5 linked sources Publisher MotherDuck Licence MIT ↗ Revision 275d2e7d2ba4 Read what was—and wasn’t—checked ↓ “Supports connecting to local DuckDB files, in-memory databases, S3-hosted databases, and MotherDuck.” MotherDuck · upstream description ↗ Our analysis follows below. 01 / THE REASONING ## Why this made the selection. - Documents file, in-memory and MotherDuck modes separately, including their different write behavior. - The local-file mode can use temporary connections to avoid holding the database file lock. ### A good fit for - Exploring a local DuckDB dataset without enabling ordinary database writes. ### Weigh up before choosing - Read-only mode is not a filesystem sandbox and does not block every sensitive DuckDB operation. - In-memory databases require write mode; MotherDuck read-only access needs a read-scaling token. 02 / THE REVIEW RECORD ## What we actually inspected. Source review has boundaries. A clear record is more useful than a “safe” badge. ### Material inspected - README.md (installation, capability and permission sections) - pyproject.toml - src/mcp_server_motherduck/server.py - src/mcp_server_motherduck/__init__.py - LICENSE ### Our findings - The CLI converts --read-write into the read_only argument and rejects read-only in-memory startup. - The CLI’s http transport is Streamable HTTP; old stream/sse aliases are converted to HTTP. ### Not established by this review - Server startup, authentication and tool execution were not tested. The review applies to the material and revision named here. A newer upstream release can change its behavior. 03 / PUT IT TO WORK ## Connect a server deliberately. Upstream setup instructions ↗ - Use the documented uvx client configuration with an absolute path to an existing DuckDB file. - For MotherDuck, choose the appropriate token type and configure its connection separately; review the production-hardening guidance. ### Before you start - uv/Python and a DuckDB file, or a MotherDuck account with an appropriate token. ### Compatibility An MCP client supporting stdio, Streamable HTTP. · uv/Python and a DuckDB file, or a MotherDuck account with an appropriate token. ### Implementation Python ### Transports stdio · Streamable HTTP ### Local analytics / Configured credentials or local access - Reads local or remote database data; --read-write enables database mutations. - DuckDB queries can interact with local files and external data sources. ### Cost model Local compute or MotherDuck query/storage usage determines cost. 04 / FOLLOW THE EVIDENCE ## The source trail. Our notes are separate from the original resource. Check upstream before adopting a new version. - Official documentation ↗ Checked 2026-09-21 https://github.com/motherduckdb/mcp-server-motherduck/blob/275d2e7d2ba4f5b48ce8ad3f01a9aeea8bd08616/README.md Supports: summary, whySelected, bestFor, limitations, install, access, compatibility, transports - Applicable source licence ↗ Checked 2026-09-21 https://github.com/motherduckdb/mcp-server-motherduck/blob/275d2e7d2ba4f5b48ce8ad3f01a9aeea8bd08616/LICENSE Supports: license - Implementation: pyproject.toml ↗ Checked 2026-09-21 https://github.com/motherduckdb/mcp-server-motherduck/blob/275d2e7d2ba4f5b48ce8ad3f01a9aeea8bd08616/pyproject.toml Supports: language, review - Implementation: src/mcp_server_motherduck/server.py ↗ Checked 2026-09-21 https://github.com/motherduckdb/mcp-server-motherduck/blob/275d2e7d2ba4f5b48ce8ad3f01a9aeea8bd08616/src/mcp_server_motherduck/server.py Supports: language, review - Implementation: src/mcp_server_motherduck/__init__.py ↗ Checked 2026-09-21 https://github.com/motherduckdb/mcp-server-motherduck/blob/275d2e7d2ba4f5b48ce8ad3f01a9aeea8bd08616/src/mcp_server_motherduck/__init__.py Supports: language, review KEEP COMPARING ## Other approaches to consider. Related by category or shared topics. These are alternatives to inspect, not a measured quality order. [### AWS IaC MCP Server ↗ Validates CloudFormation templates, retrieves CDK/CloudFormation guidance and investigates failed deployments.](/mcp-servers/aws-iac/)[### Chroma MCP ↗ Lets an assistant create and query Chroma collections through local, HTTP or Chroma Cloud database connections.](/mcp-servers/chroma/)[### ClickHouse MCP Server ↗ Queries ClickHouse and inspects table metadata, with read-only SQL by default and separate authentication for network transports.](/mcp-servers/clickhouse/) [AI Tools ↗](/tools/)[Skills ↗](/skills/)[Agents ↗](/agents/)[MCP Servers ↗](/mcp-servers/)