Dev

[Alexandre-Roussel48]

This pull request introduces the initial implementation of an Arithmetic & Logic Model Context Protocol (MCP) server in Scala 3, built with ZIO and Circe. It establishes a modular, testable architecture for serving arithmetic and logic tools over a JSON-RPC (STDIO) transport, with Docker support and detailed documentation. The changes include the core server entrypoint, protocol models, routing and error handling, configuration, and build infrastructure.

Key changes:

Core Server Architecture

• Added Main.scala, which composes ZIO layers for configuration, session management, tool registry, routing, and STDIO transport, then starts the main server loop to read and handle JSON-RPC messages.
• Introduced a modular package structure for transport, router, session, tools, model, config, and utility code, as described in the new documentation.

Protocol and Data Models

• Implemented JSON-RPC protocol models: JsonRpcMessage, JsonRpcId, and JsonRpcError with Circe codecs for serialization and deserialization. [1] [2] [3]
• Added MCP protocol models for initialization, capabilities, and tool invocation, including InitializeParams, InitializeResult, ToolDefinition, and related types. [1] [2] [3]

Routing and Error Handling

• Added RequestRouter, InitializeHandler, and ToolsHandler for dispatching and handling JSON-RPC requests, including robust error mapping from domain errors to JSON-RPC errors. [1] [2]

Configuration and Build

• Defined ServerConfig and ServerInfo for server metadata and capabilities, provided as a ZIO layer.
• Added a multi-stage Dockerfile for building and running the server as a container, and included SBT build configuration and the sbt-assembly plugin for fat JAR packaging. [1] [2] [3]

Documentation

• Rewrote README.md to provide a comprehensive overview of the server's architecture, usage, Docker integration, VS Code setup, and testing approach, targeting both contributors and end users.