Sigmatek LASAL MCP Server

A Model Context Protocol (MCP) server for automating the Sigmatek LASAL software suite. It gives AI coding assistants (Claude, Gemini, Cursor, etc.) the ability to compile, deploy to hardware, control PLCs, read/write live values, run HMI simulations, and validate project GUIDs — while the agent edits project files directly.

Warning: This is NOT an official Sigmatek product. This project is in active development — bugs and unpredictable behavior are likely. Do not use on production projects without backups or version control.

Design Philosophy

The MCP only exposes tools for operations that require an external engine or hardware — compiling, deploying, PLC control, LARS soft-runtime simulations — plus the class/manifest operations whose generated formats and caches make raw file edits error-prone (creating a class, registering project files, latin1-safe class source access, resolving GUID collisions). For everything else (reading/editing .lcp, .lcn, .lss, .lvp, dashboard JSON), the AI agent works with the files directly using its native file tools. This keeps the tool set small, reliable, and focused.

Features

• Build & Deploy: Compile CLASS 2 projects, download to PLC, full deploy pipelines (build_project, deploy_all), bootdisk/update-stick creation (plain or Update-Tool flavor with Autoexec, LasalOS image, VISU publish folder; create_class2_bootdisk).
• Multi-Station Deploy: MachineManager .lutc orchestration — CLASS 2, LASAL SCREEN and VISUDesigner downloads, OS updates, file transfer, run/boot, channel writes, CLI commands (deploy_solution), with the per-run MachineManager log returned for diagnosis.
• Background Jobs: build_project, deploy_all, deploy_solution and lse_project accept async: true and return a jobId — poll with check_job_status (useful for clients with request timeouts).
• Headless Hardening: modal engine dialogs (error boxes, crash reporters, WerFault) are auto-dismissed while script runs execute — their text is captured into the tool result instead of hanging the run until someone clicks OK (LASAL_MCP_DIALOG_WATCHER=0 disables).
• PLC Control: Start/stop PLC runtime, read/write live channel values, query state (control_plc, plc_values).
• Local Simulation (LARS): Run one LASAL program per LARS instance — one workspace per station (PLC + HMI) so both run simultaneously on separate ports. Point stations at the local runtime with a single call, compile/download/start/read values exactly like a real PLC, and browse the HMI via DataService. LARS also renders LASAL SCREEN projects locally, with window screenshots for visual verification. No hardware needed (lars_runtime).
• CLASS 2 Batch Engine: Create/delete networks, add/remove objects, manage connections, configure tasks — operations that require the CLASS 2 scripting engine (apply_project_changes, run_class2_script).
• GUID & CRC-32 Validation: Auto-resolve duplicate GUID collisions across classes/MaeExp.txt and compute exact IEEE 802.3 CRC-32 hashes for @CT_ tables (validate_guids).
• VISUDesigner Engine: Sync datapoints, manage text lists/schemes/media, publish, download to HMI (visu_project).
• LASAL SCREEN (LSE) Engine: Drive classic panel HMI .lpr projects via the LASALScreen COM automation — inventory, compile, download, merge/fuse, text-list translation edits, variable import from CLASS 2, bulk theming, settings (lse_project).
• HMI Simulation: Local web runtime via LasalVISUDataService returning accessible HTTP URLs for browser inspection or external Playwright MCP testing (hmi_runtime).
• PLC Diagnostics: Tracing, file transfer, static code analysis (plc_diagnostics).
• MCP Resources: Built-in resources for file documentation (lasal://guide), live project status (lasal://project/status), active stations (lasal://stations), and class sources (lasal://classes/{className}).
• Autocompletions: Context-aware MCP completions for class names and station names.

Prerequisites

• Windows OS (Sigmatek LASAL suite runs exclusively on Windows).
• Node.js v18 or higher.
• Sigmatek LASAL Suite:
  • LASAL CLASS 2 (PLC engineering).
  • VISUDesigner (web HMI design).
  • LASAL SCREEN (LSE, classic panel HMI design — required for lse_project).
  • MachineManager (optional — required for deploy_solution).

Quick Start (with npx)

No repository clone or build required — configure your favorite MCP client to run directly via npx:

Claude Desktop

Add to %APPDATA%\Claude\claude_desktop_config.json:

{
  "mcpServers": {
    "lasal-mcp": {
      "command": "npx",
      "args": ["-y", "lasal-mcp"]
    }
  }
}

Cursor

Add to your project's .cursor/mcp.json (or global Cursor MCP settings):

{
  "mcpServers": {
    "lasal-mcp": {
      "command": "npx",
      "args": ["-y", "lasal-mcp"]
    }
  }
}

Claude Code

Run:

claude mcp add lasal-mcp npx -y lasal-mcp

Local Installation & Setup (for Developers)

git clone https://github.com/Svel26/Lasal-MCP.git
cd Lasal-MCP
npm install
npm run build

When running from a local clone, point your MCP client to:

{
  "mcpServers": {
    "lasal-mcp": {
      "command": "node",
      "args": ["C:/path/to/Lasal-MCP/dist/server.js"]
    }
  }
}

Configuration

Environment Variables

| Variable | Default | Purpose | |---|---|---| | LASAL_CLASS2_EXE | C:\Program Files (x86)\Sigmatek\Lasal\Class2\Bin\Lasal2.exe | CLASS 2 IDE path | | LASAL_VISUDESIGNER_EXE | C:\Program Files\Sigmatek\Lasal\VISUDesigner\VISUDesigner.exe | VISUDesigner path | | LASAL_SCREEN_EXE | C:\Program Files (x86)\Sigmatek\Lasal\Screen\LSE_modeless.exe | LASAL SCREEN (LSE) editor / COM automation server path | | LASAL_MACHINEMANAGER_EXE | C:\Program Files (x86)\Sigmatek\Lasal\MachineManager\Bin\MachineManager.exe | MachineManager path | | LASAL_DATASERVICE_EXE | auto-discovered (latest version) | DataService path | | LASAL_MCP_TIMEOUT_COMPILE | 600000 | Compile timeout (ms) | | LASAL_MCP_TIMEOUT_DOWNLOAD | 600000 | Download timeout (ms) | | LASAL_MCP_TIMEOUT_VISU | 300000 | Visu operation timeout (ms) | | LASAL_MCP_TIMEOUT_SCRIPT | 120000 | Script execution timeout (ms) | | LASAL_MCP_TIMEOUT_LSE | 300000 | LASAL SCREEN operation timeout (ms) | | LASAL_MCP_TIMEOUT_MM | 900000 | MachineManager update timeout (ms) | | LASAL_MCP_DIALOG_WATCHER | 1 | Auto-dismiss modal engine dialogs during script runs and report their text. Set to 0 to disable. | | LASAL_LARS_EXE | C:\Program Files (x86)\Sigmatek\Lars\Lars.exe | LARS runtime path | | LASAL_LARS_CONFIG | %APPDATA%\lasalos2.xml | LARS workspace config file | | LASAL_MCP_HMI_DIR | C:\lslvisu | Local HMI runtime directory | | LASAL_MCP_SCRATCH_MAX_AGE_H | 24 | Hours before temp files are cleaned |

Available Tools

Engine & Hardware Tools (MCP)

| Tool | Description | |---|---| | select_project | Set the active project root directory. | | lasal_status | Check project, stations, engines, processes, HMI health. | | check_job_status | Poll background jobs started with async: true (or list recent jobs). | | inspect_project | Read-only class/network/object inventory (channels, tasks) from the manifest + class sources. | | validate_guids | Scan a station project for duplicate GUID collisions and uninitialized TO_UDINT(0) placeholders; auto-resolves GUID collisions and populates exact CRC-32 @CT_ hashes. | | read_class_source | Read or write a class .st (and optional .h) by class name; latin1-validated. | | set_target_ip | Update a station's target IP/port/SSL in its .lss, preserving other settings. | | manage_class2 | Open or close the CLASS 2 IDE. | | manage_visudesigner | Open or close VISUDesigner. | | manage_lasalscreen | Open or close the LASAL SCREEN (LSE) editor. | | build_project | Compile or download to PLC (supports async: true). | | create_class2_bootdisk | Create a CLASS 2 bootdisk / update stick (plain or Update-Tool flavor with Autoexec, OS image, VISU publish folder). | | control_plc | Start, stop, or query PLC runtime state. | | plc_values | Read/write live channel values on a running PLC. | | lars_runtime | Local LARS simulation: list/setup workspaces per station (wires CLASS 2 + LASAL SCREEN projects), start/stop, simulate (one-call loop: ARM→PC switch, compile, download, start), screenshot of the rendered screen, point stations at LARS (set_station_target), revert (restore), switch ARM projects to the PC target (target_pc). | | apply_project_changes | Batch engine operations (networks, objects, connections, tasks, compiler version, compile/download) and file-level class operations: create_class, add_project_file, clean_project (incl. deep artifact purge). | | run_class2_script | Escape hatch: run arbitrary Python 2.7 batch statements through Lasal2.exe for API calls not exposed as operations. | | visu_project | VISUDesigner engine operations (text lists, schemes, media, publish, download). | | lse_project | LASAL SCREEN engine operations via COM automation: info, compile, download, merge/fuse, XML text export/import, CLASS 2 variable import, text-list translations, bulk button/softkey theming, settings, images. | | hmi_runtime | Start/stop local HMI web simulation (DataService) and return accessible URL. | | plc_diagnostics | Tracing (DataAnalyzer), file transfer on the control, code analysis (project or single file), OS download, RAM-image clear, project-on-PLC backup, connection-file download. | | deploy_all | Full pipeline: compile → download → start PLC → compile LASAL SCREEN → optional SCREEN download → sync visu → start HMI. | | deploy_solution | Multi-station MachineManager deploy via generated .lutc: CLASS 2 / LASAL SCREEN / VISUDesigner downloads, OS, files, run/boot, writes, CLI. |

MCP Resources

| URI | Description | |---|---| | lasal://guide | Comprehensive guide on LASAL file formats, ST structure, and runtime JS API. | | lasal://project/status | Dynamic JSON resource reporting selected project, discovered stations, HMI runtime status, and LARS instances. | | lasal://stations | Live list of stations in the active solution and their target connections. | | lasal://classes/{className} | Direct read access to Structured Text (.st) sources by class name with autocompletion. |

Direct File Editing (no MCP needed)

The agent edits these files directly with its native file tools:

| File | Format | Encoding | What it contains | |---|---|---|---| | .lsm | XML | latin1 | Solution — lists all stations | | .lss | XML | latin1 | Station settings — target IP, project references | | .lcp | XML | latin1 | CLASS 2 project manifest — class and network file paths | | .st | Generated declaration + ST | latin1 | Class source — //{{LSL_DECLARATION metadata, class body, @CT_ table, methods; prefer read_class_source | | .lcn | XML | latin1 | Network definitions — objects, connections, init values | | .lvp | Mixed | utf-8 | VISUDesigner project manifest | | .lpr | Binary | mixed | LASAL SCREEN project — never edit directly; drive via lse_project | | LSEOnlineConfig.xml | XML | latin1 | LASAL SCREEN online/download target (updated by set_target_ip) | | Dashboard JSON | JSON | utf-8 | HMI dashboards, windows, controls, property bindings |

See the built-in lasal://guide resource for detailed file format documentation.

Development

npm run dev          # Watch mode
npm test             # Run unit tests (Vitest)
npm run test:lab     # Integration tests against the local LASAL installation (creates fresh projects)
npm run test:watch   # Tests in watch mode
npm run lint         # ESLint
npm run format       # Prettier
npm run inspector    # MCP Inspector for interactive debugging

Simulating without hardware (LARS)

LARS (LASAL Runtime System) runs LASAL programs on a normal PC. Since each LARS instance runs one program, the MCP creates one workspace per station:

1. lars_runtime setup — creates workspaces for every station in the selected solution (distinct ports per instance).
2. lars_runtime start <station> — launches the LARS window for that station.
3. lars_runtime set_station_target <station> — points the station's .lss at the LARS instance.
4. Now build_project, control_plc, and plc_values work unchanged against the local runtime.
5. lars_runtime restore <station> — reverts the .lss to the real hardware target.

Shortcut: lars_runtime simulate does the whole loop in one call — creates the workspace if needed (CLASS 2 + LASAL SCREEN), switches ARM targets to PC, compiles, downloads to the LARS instance and starts it.

Notes:

• Projects compiled for Processor="ARM" (most machine PLCs) need lars_runtime target_pc first — LARS is an x86 runtime and rejects ARM images.
• HMI panel / Local stations are already PC-targeted and work directly.
• Downloads to LARS automatically include the PC loader (addLoaderAnyway).
• hmi_runtime remaps published stations.json entries to running LARS instances, so the web HMI talks to the local simulation.
• Stations with a LASAL SCREEN project get their .lpr wired into the LARS workspace (SCREEN_PRJ_PATH), so LARS renders the panel screens locally; lars_runtime screenshot returns a PNG of the window for visual verification.

Contributing

Contributions are welcome! Please check out CONTRIBUTING.md for guidelines on code standards, adding tools, and submitting pull requests.

Releasing & CI/CD

Automated releases and publishing to npm are powered by GitHub Actions. Releases can be triggered manually via workflow dispatch with automated version bumping or by pushing version tags (v*.*.*).

License

This project is licensed under the MIT License.