The MCP server for your database
A single binary MCP server that gives Claude, Cursor, and any MCP client safe, read-only access to your PostgreSQL database. Runs locally over stdio or HTTP — your credentials never leave your machine.
3
MCP Tools
1
Single Binary
100%
Read-Only Queries
Zero
Credentials in the Cloud
Features
Secure by design, simple by default
Everything you need to safely connect AI to your PostgreSQL database — install, configure, done.
Local-Only, Zero-Trust
Runs on your machine as a single binary. Database credentials never leave your infrastructure — no cloud, no open ports, no third-party access.
Deep Schema Discovery
Maps schemas, tables, columns, indexes, foreign keys, and row counts. Three MCP tools give AI everything it needs to explore and query your data.
Defense in Depth
SQL parsed at the AST level — only SELECT and EXPLAIN pass. Queries run inside read-only transactions with row limits and timeouts. Multiple layers, no single point of failure.
Audit Logging & OpenTelemetry
Every query logged to an NDJSON audit trail. OpenTelemetry traces and metrics — query duration, error rates, tool call latency — export to Jaeger, Grafana, or any OTLP backend.
Policy Engine & Column Masking
Enrich schema with business context via YAML policies. Mask sensitive columns — redact, hash, partially reveal, or nullify — enforced server-side so AI never sees raw PII.
Stdio & HTTP Streamable Transport
Works with Claude Desktop, Cursor, VS Code, and ChatGPT. Serves MCP over stdio for local use or HTTP Streamable for web clients and remote access.
Pricing
Free and open source
Isthmus is Apache 2.0 licensed. No limits, no paywalls, no usage tracking. Just install and go.
Open Source
Everything you need to connect AI to your PostgreSQL database.
- Unlimited databases
- All 3 MCP tools
- AST-level SQL validation
- Read-only transactions
- Audit logging
- YAML policy engine
- Schema filtering
- Works with all MCP clients