MotherDuckSAFE
Local MCP server for DuckDB and MotherDuck
Overview
From the repository's own README, as read at the audited commit. Badges and raw HTML are left out.
DuckDB / MotherDuck Local MCP Server
SQL analytics and data engineering for AI Assistants and IDEs.
Connect AI assistants to your data using DuckDB's powerful analytical SQL engine. Supports connecting to local DuckDB files, in-memory databases, S3-hosted databases, and MotherDuck. Allows executing SQL read- and write-queries, browsing database catalogs, and switching between different database connections on-the-fly.
Looking for a fully-managed remote MCP server for MotherDuck? → Go to the MotherDuck Remote MCP docs
Remote vs Local MCP
📝 Migrating from v0.x? - Read-only by default: The server now runs in read-only mode by default. Add--read-writeto enable write access. See Securing for Production. - Default database changed:--db-pathdefault changed frommd:to:memory:. Add--db-path md:explicitly for MotherDuck. - MotherDuck read-only requires read-scaling token: MotherDuck connections in read-only mode require a read-scaling token. Regular tokens require--read-write.
Quick Start
Prerequisites: Install uv via pip install uv or brew install uv
Connecting to In-Memory Duc
43b231d587acOBSERVED · 2026-09-30Connect
Built from this server's own package name, version and transport as found in its source — not copied from anyone's documentation, so it cannot drift against a page we do not control. Replace the environment placeholders with a token scoped to the least it needs.
claude mcp add mcp-server-motherduck --env motherduck_token=${motherduck_token} --env MOTHERDUCK_TOKEN=${MOTHERDUCK_TOKEN} --env AWS_ACCESS_KEY_ID=${AWS_ACCESS_KEY_ID} --env AWS_SECRET_ACCESS_KEY=${AWS_SECRET_ACCESS_KEY} -- None mcp-server-motherduck==1.0.8Exposed tools (3)
3 read · 0 write · 0 destructive.
| Tool | Risk | Description |
|---|---|---|
list_columns | read | |
list_databases | read | |
list_tables | read |
Trust audit
SAFEgrade B · trust 89/100 Nothing in the source contradicts what it says it does. Grade A is reserved for packages that have also passed the behavioural sandbox.
| Layer | What it checks | Result |
|---|---|---|
| L0 | Provenance & inventory | PASS |
| L1 | Static analysis of the code | PASS |
| L2 | Instruction surface (what it tells the agent) | PASS |
| L3 | Class-specific surface | PASS |
| L4 | Behavioural (sandbox) | SKIPPED |
What the source does
- Filesystem
- none-observed
- Network
- none-observed
- Shell
- none-observed
- Dependencies
- pinned
- Secrets in source
- none-found
Findings (4)
.mcpbignore
.pre-commit-config.yaml
f"http://127.0.0.1:{port}/mcp/",f"http://127.0.0.1:{port}/mcp/",Gates applied: no_behavioural_pass.
43b231d587acfull audit observations/trust-audit/mcp-server/motherduckdb__motherduck.json · Report an issue / request a re-scanAudit history
Every audit this server has had. A grade with a past is a grade somebody is still checking.
| Date | Source | Verdict | Grade | Score | Change |
|---|---|---|---|---|---|
| 2026-09-30 | 43b231d587ac | SAFE | B | 89 | first audit |
Questions
What is the MotherDuck MCP server?
Local MCP server for DuckDB and MotherDuck
What tools does MotherDuck expose?
3 in total: 3 read-only, 0 that write, and 0 that can delete or overwrite. Every one is listed on this page with its risk.
Is MotherDuck safe to connect to an agent?
The audit found nothing in the source that contradicts what it says it does, and graded it B (89/100). Grade A is held back for packages that have also passed a sandboxed behavioural run, which is why a clean server reads B.
What credentials does MotherDuck need?
It reads AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_SESSION_TOKEN, E2E_USER_1_AWS_ACCESS_KEY_ID, E2E_USER_1_AWS_SECRET_ACCESS_KEY, MOTHERDUCK_TOKEN and MOTHERDUCK_TOKEN_READ_SCALING from the environment. Give it a token scoped to the least it needs — an agent that can be talked into calling a tool can be talked into calling it with your credentials.
How does MotherDuck run?
It speaks stdio and streamable-http, so it runs as a local process your client starts. It is published on PyPI as mcp-server-motherduck.
How current is this page?
The grade is for one exact copy of the source (43b231d587ac), read on 2026-09-30. The repository is watched and re-audited when it changes.