Library and Server

mcbox is designed around a clear architectural separation between library and server implementation. This design enables users to either configure and run the provided reference server or build completely custom MCP servers using the core functionality.

mcbox-core.bash (Library)

The core library contains all the fundamental MCP protocol functions and utilities needed to build an MCP server in Bash. It provides:

• MCP Protocol Handling - Complete JSON-RPC and MCP message processing
• Configuration Management - Functions to load and validate server and tool configurations
• Tool Execution Engine - Framework for discovering, validating, and executing tool functions
• JSON Processing - Utilities for JSON schema validation and manipulation
• Error Handling and Logging - Standardized error responses and logging

The library is purely functional - it defines capabilities but doesn’t run anything by itself. You can source it in any Bash script to gain MCP server functionality.

mcbox-server.bash (Reference Implementation)

The reference server is a complete, working MCP server that uses the core library. It provides:

• Signal Handling - Graceful shutdown on SIGINT/SIGTERM, configuration reload on SIGHUP
• Configuration Loading - Automatic discovery and loading of configuration files
• Server Loop - The main mcp_server event loop that processes incoming requests
• Default Behavior - Sensible defaults for a typical MCP server deployment

This is what most users will run directly, but it’s also a template for building custom servers.