Add support for Model Context Protocol

[martin-fleck-at]

What it does

• Add new package to start a MCP server as part of the GLSP server
  • Start MCP HTTP server for client connections on GLSP server start
  • Provide some default tools and resources
  • Expose functionality as custom module
• Extend examples to use GLSP MCP Server

Part of eclipse-glsp/glsp#1546
Requires eclipse-glsp/glsp-client#456

How to test

• Start the node server
• Connect with a client that sets the mcpServer configuration
• Read the actual url of the server out of the log, e.g., [McpServerManager] MCP server 'glspMcpServer' is ready to accept new client requests on: http://127.0.0.1:5555/glsp-mcp
• Connect to the server using the Theia Integration (caution: no support for MCP Resources) or Claude Code or the MCP Inspector.
• Test querying resources and tools

Follow-ups

Changelog

• This PR should be mentioned in the changelog
• This PR introduces a breaking change (if yes, provide more details below for the changelog and the migration guide)

[Copilot]

Pull request overview

This PR adds Model Context Protocol (MCP) support to the GLSP server, enabling AI assistants and other MCP clients to interact with GLSP diagrams through a standardized protocol. The implementation provides HTTP-based MCP server functionality with default tools for diagram manipulation and resources for querying diagram state.

Key changes:

• Introduces new @eclipse-glsp/server-mcp package with MCP server infrastructure, HTTP transport layer, and default tools/resources for diagram interaction
• Extends GLSP server initialization to support contributions via GLSPServerInitContribution interface
• Updates workflow example to demonstrate MCP integration

Reviewed changes

Copilot reviewed 19 out of 21 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/server/src/common/session/client-session-manager.ts	Adds getSessions() method to retrieve all active client sessions
packages/server/src/common/protocol/glsp-server.ts	Introduces GLSPServerInitContribution mechanism and deprecates handleInitializeArgs
packages/server/src/common/di/server-module.ts	Adds binding configuration for GLSPServerInitContribution
packages/server-mcp/tsconfig.json	TypeScript configuration for new MCP package
packages/server-mcp/src/mcp-util.ts	Utility functions for MCP parameter extraction and result formatting
packages/server-mcp/src/mcp-server-manager.ts	Core MCP server lifecycle management and HTTP server initialization
packages/server-mcp/src/mcp-server-contribution.ts	Interface for extending MCP server with custom tools and resources
packages/server-mcp/src/index.ts	Package exports
packages/server-mcp/src/http-server-with-sessions.ts	HTTP server implementation with MCP session management
packages/server-mcp/src/di.config.ts	Dependency injection configuration for MCP module
packages/server-mcp/src/default-mcp-tool-contribution.ts	Default MCP tools for diagram validation, element creation, undo/redo, and save operations
packages/server-mcp/src/default-mcp-resource-contribution.ts	Default MCP resources for querying sessions, diagram types, element types, and models
packages/server-mcp/package.json	Package metadata and dependencies for MCP package
packages/server-mcp/.eslintrc.js	ESLint configuration ignoring MCP SDK imports
examples/workflow-server/tsconfig.json	Adds reference to server-mcp package
examples/workflow-server/src/node/app.ts	Integrates MCP module into workflow server
examples/workflow-server/src/common/workflow-glsp-server.ts	Migrates from deprecated handleInitializeArgs to GLSPServerInitContribution
examples/workflow-server/src/common/workflow-diagram-module.ts	Updates binding to use new init contribution pattern
examples/workflow-server/package.json	Adds dependency on server-mcp package

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