PostgREST MCP Server

A complete PostgREST MCP (Model Context Protocol) server that uses OAuth2 for authentication. Works with any PostgREST server. Currently tested with NEON and Supabase.

Built with Hono and supports Streamable HTTP.

Deployment Options

The server can be deployed to:

• Supabase Edge Functions - default configuration is auto-detected
• Cloudflare Workers - requires environment variable configuration
• Deno Deploy - requires environment variable configuration

When deployed to Supabase, the server automatically detects the PostgREST API endpoint and authentication configuration. For other providers (NEON, custom PostgREST servers), environment variables need to be configured.

Environment Variables

AUTH_SERVER_URL

OAuth authorization server URL. Required for Cloudflare Workers and Deno Deploy deployments.

Optional when deployed as a Supabase Edge Function - will be auto-constructed from the automatically available SUPABASE_URL environment variable as {origin}/auth/v1.

Example: https://jdnlvjebzatlybaysdcp.supabase.co/auth/v1

API_BASE_URL

PostgREST server URL for making API requests.

Optional when SUPABASE_URL is set - will be auto-constructed as {origin}/rest/v1 from the SUPABASE_URL. Set this variable to override the auto-constructed URL.

Example: https://jdnlvjebzatlybaysdcp.supabase.co/rest/v1

API_KEY

API key sent in the apikey header for PostgREST requests.

Takes precedence over SUPABASE_ANON_KEY when both are set. Use this to override the Supabase anonymous key with a custom API key.

Example: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...

SUPABASE_ANON_KEY

Supabase anonymous key used as the apikey header for PostgREST requests when API_KEY is not provided.

Automatically available when deployed as a Supabase Edge Function. For local development or non-Supabase deployments, you need to set this manually.

Example: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...

Supabase Edge Functions

This server supports MCP authentication from the Supabase OAuth2 server.

Environment: When deployed as a Supabase Edge Function, the SUPABASE_URL environment variable is automatically available. The server will auto-construct the AUTH_SERVER_URL from it (as {origin}/auth/v1), so no additional environment configuration is needed.

Prerequisites

Supabase CLI should be installed. If needed, install it as a dependency:

# Install as dev dependency
pnpm add -D supabase

Development

deno task supabase:dev

The MCP endpoint will be available at: http://localhost:54321/functions/v1/postgrest-mcp/mcp

Deployment

First, link your project (one-time setup):

supabase link --project-ref <your-project-ref>

Note: Find your project ref in your Supabase dashboard URL: https://supabase.com/dashboard/project/<your-project-ref> or in Project Settings > General > Reference ID

Then deploy the function:

deno task supabase:deploy

The MCP endpoint will be available at: https://<your-project-ref>.supabase.co/functions/v1/postgrest-mcp/mcp

Note on MCP Inspector Compatibility (January 2026): The MCP Inspector is not yet compliant with RFC 9728 and does not properly handle the resource_metadata parameter in WWW-Authenticate headers. This causes issues when the OAuth metadata endpoint is served at an uncommon path like /functions/v1/postgrest-mcp/.well-known/oauth-protected-resource. Claude Desktop and Claude Web handle this correctly and will successfully discover the metadata endpoint. See Inspector issue #576 for details.

Cloudflare Workers

Development

pnpm cloudflare:dev

The MCP endpoint will be available at: http://localhost:3000/mcp

Deployment

pnpm cloudflare:deploy

The MCP endpoint will be available at: https://<your-worker>.workers.dev/mcp

Deno

Prerequisites

Install Deno:

# macOS/Linux
curl -fsSL https://deno.land/install.sh | sh

# Windows
irm https://deno.land/install.ps1 | iex

Development

pnpm deno:dev
# or directly with deno
deno task dev

The MCP endpoint will be available at: http://localhost:8000/mcp

Deployment

First, create a new project (one-time setup):

deno deploy create --org=<your-org>

Then deploy:

deno task deploy

The MCP endpoint will be available at: https://<your-project>.deno.dev/mcp

Credits

This implementation is based on supabase-mcp.