A open source RESTful web service API with MCP AI support for multi-lingual translations of the Christian bible, built with Rails and PostgreSQL.

Included data import utilities load the entire the Bible Databases project, which you must clone locally.

# Set your database URL
export BIBLER_SERVER_DATABASE_URL="postgresql://bibler:password@localhost:5432/bibler_development"
# Set path to local clone of bible data project
export BIBLER_SERVER_BIBLE_DATABASES_PATH=../bible_databases

bundle install # Install ruby dependencies.
rake db:migrate # Create the database
rake bibler:import[../bible_databases] # Load bible data project. Will take a while.
rails s # Run the server.

The server will be running at http://localhost:3000

Bibler Server is a bible study API provided as a Rails application, and is pre-built and distributed via Docker Hub.

See Bibler UI for the web frontend:

• GitHub: https://github.com/preston/bibler-ui
• Docker Build: https://hub.docker.com/r/p3000/bibler-ui

Custom Bibler Server distributions can be build with Docker or compatible build systems. To build,

docker buildx build --platform linux/arm64,linux/amd64 -t p3000/bibler-server:latest . --push

To run it:

docker run -it --rm -p 8080:3000 --name bibler-server \
-e "BIBLER_SERVER_DATABASE_URL=postgresql://bibler:[email protected]:5432/bibler_development" \
-e "BIBLER_SERVER_SECRET_KEY_BASE=super_secret" \
-e "BIBLER_SERVER_MIN_THREADS=4" \
p3000/bibler-server:latest

To load the database, clone the Bible Databases project locally and run:

rake bibler:import[/path/to/bible_databases]

Bibler server supports Model Context Protocol (MCP), allowing AI agents to discover and use it as research tool.

Use the official MCP Inspector tool to test and debug the MCP server:

1. Start the Bibler server:

   rails s

2. In a separate terminal, run the MCP Inspector with increased timeout:

   MCP_SERVER_REQUEST_TIMEOUT=30000 npx @modelcontextprotocol/inspector

   Or use the Inspector's direct connection mode:

   npx @modelcontextprotocol/inspector --url http://localhost:3000/mcp

3. The Inspector UI should open in your web browser.

4. If connecting manually in the UI:

   • Transport: Streamable HTTP (or HTTP Stream)
   • URL: http://localhost:3000/mcp
   • Connection Type: Direct
   • No authentication required - the server accepts requests without auth headers

5. Use the Inspector to:

   • View available tools in the Tools tab
   • Test tool calls with different parameters
   • Monitor server responses and notifications
   • Debug protocol-level issues

Configuration Tips:

• IMPORTANT: The Inspector may have a shorter default timeout than expected
• Increase the timeout in the Inspector UI: Click "Configuration" → "Request Timeout" → Set to at least 5000ms (5 seconds) or as appropriate for your context
• For direct connections, ensure CORS is properly configured (already set in this server)
• The Inspector will establish both a GET SSE connection (announcement channel) and POST requests (command channel)
• No authentication is required - the server accepts requests without auth headers

• search_verses: Search for verses by text query
• get_verse: Get a specific verse by reference
• get_chapter: Get all verses in a chapter
• list_books: List books in a bible
• list_bibles: List available bible translations
• get_book_info: Get information about a specific book
• list_languages: List all distinct language codes and their human-readable names

The MCP endpoint is available at: POST /mcp

For streaming responses: GET /mcp (SSE)

Author: Preston Lee