Cursor

Config file location

Cursor supports project-level and global MCP configuration:

Project (recommended)
Global

.cursor/mcp.json

Place this in your project root. Cursor reads it when you open the project.

~/.cursor/mcp.json

Applies to all projects.

Minimal configuration

{
  "mcpServers": {
    "isthmus": {
      "command": "isthmus",
      "env": {
        "DATABASE_URL": "postgres://user:password@localhost:5432/mydb"
      }
    }
  }
}

Full configuration

{
  "mcpServers": {
    "isthmus": {
      "command": "isthmus",
      "args": ["--audit-log", "/tmp/isthmus-audit.ndjson"],
      "env": {
        "DATABASE_URL": "postgres://user:password@localhost:5432/mydb",
        "SCHEMAS": "public,analytics",
        "POLICY_FILE": "/path/to/policy.yaml",
        "MAX_ROWS": "500"
      }
    }
  }
}

Verify

Save the config file
Restart Cursor or reload the window
Open the AI chat panel
Ask: “What tables are in my database?”

Troubleshooting

Binary not found

Use the full path to the binary. The location depends on how you installed:

Install script / prebuilt binary: /usr/local/bin/isthmus
go install: ~/go/bin/isthmus

"command": "/usr/local/bin/isthmus"

Find the path with which isthmus.

Config not picked up

Make sure the file is named exactly mcp.json (not mcp_config.json) and is inside the .cursor directory. Restart Cursor after creating or editing the file.

Database unreachable

Test connectivity first:

DATABASE_URL="postgres://user:password@localhost:5432/mydb" isthmus --dry-run

Getting Started

Client Setup

Features

Security

Architecture

Config file location

Minimal configuration

Full configuration

Verify

Troubleshooting

​Config file location

​Minimal configuration

​Full configuration

​Verify

​Troubleshooting

Config file location

Minimal configuration

Full configuration

Verify

Troubleshooting