Connect PostgreSQL to Claude

With an MCP server, Claude can look at your tables, write SQL and explain the result. XenMCP runs a proven open-source server for this in an isolated sandbox in Germany and gives you an address with OAuth that you add to Claude as a connector.

Protection in layers: read-only mode in the server, a database user with read rights, limits on rows and runtime, and a fixed IP address that you allow in pg_hba.conf or your firewall.

What you can ask Claude

• Which ten customers had the highest revenue last quarter?
• Describe the schema: which tables exist and how are they related?
• How many open tickets does each team have, and how old is the oldest one?
• Explain the execution plan of this query and why it is slow.
• Check whether orders has rows without a matching customer.

Typical tools

execute_sql

Run SQL – in read-only mode only SELECT, SHOW, EXPLAIN and the like

search_objects

Find schemas, tables, columns and indexes

explain_sql

Show the execution plan

health_check

Check the state of the database

Write statements

INSERT, UPDATE, DELETE (only when you allow it, blocked by default)

What you need to connect

• Connection details (host, port, database) or a DSN postgres://…
• A dedicated database user with read rights, e.g. with the role pg_read_all_data
• XenMCP’s fixed IP address allowed in your firewall and pg_hba.conf
• A TLS connection (recommended, sslmode=require)

Security

• Read-only by default: the server blocks write statements, and a user without write rights adds a second, independent barrier.
• Row and time limits per query, so one expensive query cannot slow down your database.
• Only XenMCP’s fixed IP needs access, not the whole internet.
• Credentials encrypted (AES-256-GCM), never logged; the call log keeps only tool, status and duration, no SQL and no results.
• Its own isolated sandbox (gVisor) per server, with no access to other customers.

Built on

We use the open server DBHub (Bytebase) (MIT), build the image ourselves from a pinned version and review the tool descriptions before release.

Frequently asked questions