Self-Hosted Supabase MCP Server

Overview

This project provides a Model Context Protocol (MCP) server designed specifically for interacting with self-hosted Supabase instances. It bridges the gap between MCP clients (like IDE extensions) and your local or privately hosted Supabase projects, enabling database introspection, management, and interaction directly from your development environment.

This server was built from scratch, drawing lessons from adapting the official Supabase cloud MCP server, to provide a minimal, focused implementation tailored for the self-hosted use case.

Related MCP server: supabase-mcp

Purpose

The primary goal of this server is to enable developers using self-hosted Supabase installations to leverage MCP-based tools for tasks such as:

• Querying database schemas and data.

• Managing database migrations.

• Inspecting database statistics and connections.

• Managing authentication users.

• Interacting with Supabase Storage.

• Generating type definitions.

It avoids the complexities of the official cloud server related to multi-project management and cloud-specific APIs, offering a streamlined experience for single-project, self-hosted environments.

Features (Implemented Tools)

The server exposes the following tools to MCP clients:

• Schema & Migrations

  • list_tables: Lists tables in the database schemas.

  • list_extensions: Lists installed PostgreSQL extensions.

  • list_migrations: Lists applied Supabase migrations.

  • apply_migration: Applies a SQL migration script.

• Database Operations & Stats

  • execute_sql: Executes an arbitrary SQL query (via RPC or direct connection).

  • get_database_connections: Shows active database connections (pg_stat_activity).

  • get_database_stats: Retrieves database statistics (pg_stat_*).

• Project Configuration

  • get_project_url: Returns the configured Supabase URL.

  • verify_jwt_secret: Checks if the JWT secret is configured.

• Development & Extension Tools

  • generate_typescript_types: Generates TypeScript types from the database schema.

  • rebuild_hooks: Attempts to restart the pg_net worker (if used).

• Auth User Management

  • list_auth_users: Lists users from auth.users.

  • get_auth_user: Retrieves details for a specific user.

  • create_auth_user: Creates a new user (Requires direct DB access, insecure password handling).

  • delete_auth_user: Deletes a user (Requires direct DB access).

  • update_auth_user: Updates user details (Requires direct DB access, insecure password handling).

• Storage Insights

  • list_storage_buckets: Lists all storage buckets.

  • list_storage_objects: Lists objects within a specific bucket.

• Realtime Inspection

  • list_realtime_publications: Lists PostgreSQL publications (often supabase_realtime).

(Note:

Setup and Installation

Installing via Smithery

To install Self-Hosted Supabase MCP Server for Claude Desktop automatically via Smithery:

Prerequisites

• Node.js (Version 18.x or later recommended)

• npm (usually included with Node.js)

• Access to your self-hosted Supabase instance (URL, keys, potentially direct DB connection string).

Steps

1. Clone the repository:

   git clone <repository-url> cd selfhosted-supabase-mcp

2. Install dependencies:

   npm install

3. Build the project:

   npm run build

   This compiles the TypeScript code to JavaScript in the dist directory.

Configuration

The server requires configuration details for your Supabase instance. These can be provided via command-line arguments or environment variables. CLI arguments take precedence.

Required:

• --url <url> or SUPABASE_URL=<url>: The main HTTP URL of your Supabase project (e.g., http://localhost:8000).

• --anon-key <key> or SUPABASE_ANON_KEY=<key>: Your Supabase project's anonymous key.

Optional (but Recommended/Required for certain tools):

• --service-key <key> or SUPABASE_SERVICE_ROLE_KEY=<key>: Your Supabase project's service role key. Needed for operations requiring elevated privileges, like attempting to automatically create the execute_sql helper function if it doesn't exist.

• --db-url <url> or DATABASE_URL=<url>: The direct PostgreSQL connection string for your Supabase database (e.g., postgresql://postgres:password@localhost:5432/postgres). Required for tools needing direct database access or transactions (apply_migration, Auth tools, Storage tools, querying pg_catalog, etc.).

• --jwt-secret <secret> or SUPABASE_AUTH_JWT_SECRET=<secret>: Your Supabase project's JWT secret. Needed for tools like verify_jwt_secret.

• --tools-config <path>: Path to a JSON file specifying which tools to enable (whitelist). If omitted, all tools defined in the server are enabled. The file should have the format {"enabledTools": ["tool_name_1", "tool_name_2"]}.

Important Notes:

• execute_sql Many tools rely on a public.execute_sql function within your Supabase database for secure and efficient SQL execution via RPC. The server attempts to check for this function on startup. If it's missing and a service-key (or SUPABASE_SERVICE_ROLE_KEY) and db-url (or DATABASE_URL) are provided, it will attempt to create the function and grant necessary permissions. If creation fails or keys aren't provided, tools relying solely on RPC may fail.

• Direct Database Access: Tools interacting directly with privileged schemas (auth, storage) or system catalogs (pg_catalog) generally require the DATABASE_URL to be configured for a direct pg connection.

Usage

Run the server using Node.js, providing the necessary configuration:

The server communicates via standard input/output (stdio) and is designed to be invoked by an MCP client application (e.g., an IDE extension like Cursor). The client will connect to the server's stdio stream to list and call the available tools.

Client Configuration Examples

Below are examples of how to configure popular MCP clients to use this self-hosted server.

Important:

• Replace placeholders like <your-supabase-url>, <your-anon-key>, <your-db-url>, <path-to-dist/index.js> etc., with your actual values.

• Ensure the path to the compiled server file (dist/index.js) is correct for your system.

• Be cautious about storing sensitive keys directly in configuration files, especially if committed to version control. Consider using environment variables or more secure methods where supported by the client.

Cursor

1. Create or open the file .cursor/mcp.json in your project root.

2. Add the following configuration:

   { "mcpServers": { "selfhosted-supabase": { "command": "node", "args": [ "<path-to-dist/index.js>", // e.g., "F:/Projects/mcp-servers/self-hosted-supabase-mcp/dist/index.js" "--url", "<your-supabase-url>", // e.g., "http://localhost:8000" "--anon-key", "<your-anon-key>", // Optional - Add these if needed by the tools you use "--service-key", "<your-service-key>", "--db-url", "<your-db-url>", // e.g., "postgresql://postgres:password@host:port/postgres" "--jwt-secret", "<your-jwt-secret>", // Optional - Whitelist specific tools "--tools-config", "<path-to-your-mcp-tools.json>" // e.g., "./mcp-tools.json" ] } } }

Visual Studio Code (Copilot)

VS Code Copilot allows using environment variables populated via prompted inputs, which is more secure for keys.

1. Create or open the file .vscode/mcp.json in your project root.

2. Add the following configuration:

   { "inputs": [ { "type": "promptString", "id": "sh-supabase-url", "description": "Self-Hosted Supabase URL", "default": "http://localhost:8000" }, { "type": "promptString", "id": "sh-supabase-anon-key", "description": "Self-Hosted Supabase Anon Key", "password": true }, { "type": "promptString", "id": "sh-supabase-service-key", "description": "Self-Hosted Supabase Service Key (Optional)", "password": true, "required": false }, { "type": "promptString", "id": "sh-supabase-db-url", "description": "Self-Hosted Supabase DB URL (Optional)", "password": true, "required": false }, { "type": "promptString", "id": "sh-supabase-jwt-secret", "description": "Self-Hosted Supabase JWT Secret (Optional)", "password": true, "required": false }, { "type": "promptString", "id": "sh-supabase-server-path", "description": "Path to self-hosted-supabase-mcp/dist/index.js" }, { "type": "promptString", "id": "sh-supabase-tools-config", "description": "Path to tools config JSON (Optional, e.g., ./mcp-tools.json)", "required": false } ], "servers": { "selfhosted-supabase": { "command": "node", // Arguments are passed via environment variables set below OR direct args for non-env options "args": [ "${input:sh-supabase-server-path}", // Use direct args for options not easily map-able to standard env vars like tools-config // Check if tools-config input is provided before adding the argument ["--tools-config", "${input:sh-supabase-tools-config}"] // Alternatively, pass all as args if simpler: // "--url", "${input:sh-supabase-url}", // "--anon-key", "${input:sh-supabase-anon-key}", // ... etc ... ], "env": { "SUPABASE_URL": "${input:sh-supabase-url}", "SUPABASE_ANON_KEY": "${input:sh-supabase-anon-key}", "SUPABASE_SERVICE_ROLE_KEY": "${input:sh-supabase-service-key}", "DATABASE_URL": "${input:sh-supabase-db-url}", "SUPABASE_AUTH_JWT_SECRET": "${input:sh-supabase-jwt-secret}" // The server reads these environment variables as fallbacks if CLI args are missing } } } }

3. When you use Copilot Chat in Agent mode (@workspace), it should detect the server. You will be prompted to enter the details (URL, keys, path) when the server is first invoked.

Other Clients (Windsurf, Cline, Claude)

Adapt the configuration structure shown for Cursor or the official Supabase documentation, replacing the command and args with the node command and the arguments for this server, similar to the Cursor example:

Consult the specific documentation for each client on where to place the mcp.json or equivalent configuration file.

Docker Integration with Self-Hosted Supabase

This MCP server can be integrated directly into a self-hosted Supabase Docker Compose stack, making it available alongside other Supabase services via the Kong API gateway.

Architecture Overview

When integrated with Docker:

• The MCP server runs in HTTP transport mode (not stdio)

• It's exposed through Kong at /mcp/v1/*

• JWT authentication is handled by the MCP server itself

• The server has direct access to the database and all Supabase keys

Setup Steps

1. Add the MCP Server as a Git Submodule

From your Supabase Docker directory:

2. Create the Dockerfile

Create volumes/mcp/Dockerfile:

3. Add the MCP Service to docker-compose.yml

Add this service definition to your docker-compose.yml:

4. Add Kong API Gateway Routes

Add the MCP routes to volumes/api/kong.yml in the services section:

5. Enable the MCP Service

The MCP service uses Docker Compose profiles, so it's disabled by default. To enable it:

Option A: Set in

Option B: Enable at runtime:

Accessing the MCP Server

Once running, the MCP server is available at:

• Internal (from other containers): http://mcp:3100

• External (via Kong): http://localhost:8000/mcp/v1/

Authentication

When running in HTTP mode, the MCP server validates JWTs using the configured JWT_SECRET. Clients must include a valid Supabase JWT in the Authorization header:

The JWT's role claim determines access:

• service_role: Full access to all tools (regular, privileged, sensitive)

• authenticated: Access to regular tools only

• anon: Access to regular tools only

Health Check

The MCP server exposes a health endpoint:

Security Considerations

When deploying via Docker:

1. The MCP server runs as a non-root user (mcp:mcp)

2. JWT authentication is enforced for all tool calls

3. Privileged tools (like execute_sql) require service_role JWT

4. CORS is configured via Kong - adjust origins for your deployment

Development

• Language: TypeScript

• Build: tsc (TypeScript Compiler) or bun build

• Runtime: Node.js or Bun

• Dependencies: Managed via npm or bun (package.json)

• Core Libraries: @supabase/supabase-js, pg (node-postgres), zod (validation), commander (CLI args), @modelcontextprotocol/sdk (MCP server framework).

License

This project is licensed under the MIT License. See the LICENSE file for details.