Last verified
Postgres MCP Server
VerifiedQuery and introspect PostgreSQL databases from Claude using read-safe MCP tools
Install
npx -y @modelcontextprotocol/server-postgres postgresql://user:pass@host/dbnameTools exposed
- query
- list_tables
- describe_table
"Claude described the schema, wrote a report query, and formatted the output as a markdown table — the analyst never opened psql."
Postgres MCP Server
The Postgres MCP Server is an official MCP reference implementation that gives Claude structured, read-only access to a PostgreSQL database. It exposes three tools — query, list_tables, and describe_table — so Claude can explore schemas and run SELECT statements as part of data and databases workflows, without the risk of mutating live data.
How does it work?
Pass a PostgreSQL connection string on the command line when starting the server. The server opens a connection pool and translates each MCP tool call into the corresponding SQL command. Because write operations are not implemented, Claude cannot modify your data even if a prompt asks it to.
For local development projects that also involve source files, pairing the Postgres MCP server with the Filesystem MCP server gives Claude visibility into both the code and the database it connects to — useful when debugging ORM queries or generating migration scripts.
When to use it
Use the Postgres MCP server when a data analyst or developer wants to query a database in plain English, generate SQL for unfamiliar schemas, or produce reports without writing SQL by hand. It works well in analytics sessions where the goal is exploration rather than modification.
Frequently asked questions
Is the Postgres MCP server safe to use on a production database?
The server only exposes SELECT queries and schema introspection — INSERT, UPDATE, DELETE, and DDL statements are blocked. For additional safety, create a read-only PostgreSQL role and supply those credentials so the database enforces the restriction at the connection level.
Can I connect to a hosted database like Supabase or RDS?
Yes. Pass any valid libpq connection string as the startup argument. Ensure the server running the MCP process can reach your database host on port 5432 (or whichever port you use). For RDS, add the MCP server's IP to the security group inbound rules.
What happens if Claude generates a query that joins many large tables?
The query runs with the timeout and resource limits set by your PostgreSQL server config. Apply a `statement_timeout` at the role level (e.g., `SET statement_timeout = '10s'`) to prevent runaway queries from affecting other users on shared instances.