PLC Cloud Sim — LAD/SCL simulation over MCP

PLC Cloud Sim — MCP server for LAD / SCL simulation

Cloud PLC simulator over MCP by 汇智网 (hubwiz.com). Validate and step-run Ladder (LAD) and SCL programs, run scenario acceptance, get a PASS/FAIL report — without installing TIA Portal.

This repository is documentation and client configuration only. The simulator runs as a hosted service at tia.hubwiz.com; its implementation is not open source.

• Endpoint: https://tia.hubwiz.com/sim/mcp
• Transport: Streamable HTTP (stateless, POST JSON-RPC)
• Auth: Authorization: Bearer sim_live_… (the X-API-Key header is also accepted)
• Dashboard / API keys: https://tia.hubwiz.com/sim
• Registry entry: io.github.tia-forge/plc-cloud-sim (official MCP Registry)

What it does

Tool	Purpose
lad_validate	Validate one or more LadDoc ladder documents
lad_simulate	Run scan cycles with given inputs, read back variables and diagnostics
lad_run_scenario	Run a declarative scenario (cases / exhaustive matrix / seeded fuzz / always invariants)
scl_validate	Parse and validate SCL source
scl_simulate	Step-run SCL across scan cycles and read variables back
scl_run_scenario	Run a declarative SCL scenario

Semantics match a real PLC scan: contacts, coils, timers/counters, FC/FB calls, jumps, and IF/CASE/FOR/WHILE for SCL. Execution is deterministic and reproducible — the same input yields the same result, so a scenario is usable as a regression test.

Quick start

Claude Code

claude mcp add --transport http sim-cloud https://tia.hubwiz.com/sim/mcp \
  --header "Authorization: Bearer sim_live_YOUR_KEY"
claude mcp list

Cursor / VS Code / any JSON-configured client

{
  "mcpServers": {
    "sim-cloud": {
      "url": "https://tia.hubwiz.com/sim/mcp",
      "headers": { "Authorization": "Bearer sim_live_YOUR_KEY" }
    }
  }
}

Ask the agent for something

Validate this SCL block, then run it for two scans with Start=false then Start=true,
and tell me the final value of Motor.

Pricing

• WeChat login on the dashboard issues a key immediately: 100 calls free, no signup form.
• Top-ups: 1000 calls for ¥9, one-off — no subscription, no monthly fee.
• Handshake requests (initialize, tools/list) are free; each tools/call costs 1 call.

Notes

• No TIA Portal installation is required — the program text (LadDoc / SCL) is sent to the service. If your policy forbids uploading program text, use an on-premises path instead (see TiaLink for the on-machine gateway).
• Related services: LadDoc Cloud (LadDoc → SimaticML), TIA Portal ladder examples.
• Documentation license: CC BY 4.0. "TIA Portal", "SIMATIC" and "S7" are trademarks of Siemens AG; this service is an independent third-party tool, not affiliated with or endorsed by Siemens.