Use with Claude Desktop

Connect Claude Desktop to PostgreSQL through pREST’s read-only MCP tools. Claude can discover schemas and query data via your running pREST instance.

pREST speaks MCP over HTTP at /_mcp. Claude Desktop launches stdio MCP servers, so you need the official prest-mcp adapter as a bridge.

Requires pREST v2.1.0+.

---

Prerequisites

• pREST running locally or on a reachable host (see Get pREST)

• prest-mcp installed (Homebrew, Go, or Docker)

• Claude Desktop with MCP support

Verify the HTTP endpoint before configuring Claude:

curl -s http://localhost:3000/_mcp | head

You should see JSON with "name": "prest" and a tools array. If auth is enabled, include your usual Authorization header.

Prefer a read-only PostgreSQL role for AI access.

---

Install the adapter

brew install prest/tap/prest-mcp

Other options: Install pREST MCP Adapter. Confirm the binary is on your PATH (Claude Desktop often needs an absolute path — see below):

which prest-mcp

---

Configure Claude Desktop

Edit Claude’s MCP config file:

Platform	Path
macOS	~/Library/Application Support/Claude/claude_desktop_config.json
Windows	%APPDATA%\Claude\claude_desktop_config.json

Basic config

{
  "mcpServers": {
    "prest": {
      "command": "prest-mcp",
      "env": {
        "PREST_MCP_URL": "http://localhost:3000/_mcp"
      }
    }
  }
}

With authentication

When auth is enabled on pREST:

{
  "mcpServers": {
    "prest": {
      "command": "prest-mcp",
      "env": {
        "PREST_MCP_URL": "https://api.example.com/_mcp",
        "PREST_MCP_TOKEN": "your-jwt-here"
      }
    }
  }
}

Do not commit this file to a shared repo if it contains tokens.

Absolute path

GUI apps on macOS often have a minimal PATH. Prefer an absolute command:

{
  "mcpServers": {
    "prest": {
      "command": "/opt/homebrew/bin/prest-mcp",
      "env": {
        "PREST_MCP_URL": "http://localhost:3000/_mcp"
      }
    }
  }
}

On Intel Mac Homebrew installs, use /usr/local/bin/prest-mcp.

---

Verify in Claude Desktop

1. Fully quit and reopen Claude Desktop (MCP config is loaded at startup).

2. Open a new chat and look for the MCP / tools indicator for the prest server.

3. Ask Claude to use pREST, for example:

   • “Using the prest MCP server, list available databases.”

   • “Describe table public.users.”

   • “Fetch up to 5 rows from public.orders.”

Claude should invoke tools such as prest.list_databases, prest.describe_table, or schema-aware prest.select.* tools. See MCP over HTTP for arguments, auth, and the 100-row select limit.

---

Optional: Docker-backed adapter

{
  "mcpServers": {
    "prest": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "-e",
        "PREST_MCP_URL=http://host.docker.internal:3000/_mcp",
        "ghcr.io/prest/prest-mcp-adapter:0.1.3"
      ]
    }
  }
}

Ensure Docker Desktop is running before starting Claude.

---

Troubleshooting

Symptom	Fix
prest never appears	Quit Claude completely and reopen; check JSON syntax in the config file
Server error / spawn failed	Use an absolute path to prest-mcp; GUI apps may not see Homebrew’s PATH
Auth failures	Set PREST_MCP_TOKEN
Connection refused	Start pREST; confirm PREST_MCP_URL
Empty tools	Check permissions and curl discovery on /_mcp

Logs from the adapter go to stderr; Claude Desktop surfaces MCP server errors in its developer / MCP UI depending on version.

More detail: Install pREST MCP Adapter and MCP over HTTP.

---

Next steps

• Read-only PostgreSQL for AI

• PostgreSQL to AI agent

• Use with Cursor · Use with VS Code and Copilot

• Other AI tools

Related documentation

• MCP Overview

• MCP over HTTP

• Permissions

• Auth