CST Studio MCP/CLI

A local Python automation core for CST Studio Suite 2026.2, with a CLI (cst-rf) and a stdio MCP server (cst-rf-mcp) sharing the same service, schemas, result envelopes and audit trail.

简体中文 · Architecture · Tool catalog · Acceptance status

Development preview (0.1.0.dev0), not a fully validated unattended simulation product. Registering a tool does not mean that its CST History commands or solver behavior passed live acceptance.

Capabilities and status

• Inspect: discover/connect to a CST Design Environment, check the expected project identity, inspect the model tree, parameters, boundaries and Floquet modes. Saved results and the locally installed CST help can be read offline.

• Model safely: copy a source .cst project to an operation-specific scratch, then use structured parameters and fixed History templates; source projects are never live write targets. No arbitrary VBA or shell execution is exposed.

• Metasurfaces: set Floquet mode counts and incidence angles; calculate R/T/A and PCR from explicit saved complex channels and their real frequency axes. Export CSV, HTML and Touchstone with the recorded reference impedance. A claimed T=0 is an assumption requiring independent complete-backplane evidence, not an inference from missing transmission data.

• Jobs and safety: require confirm=true for mutation and solver actions, confine writes to CST_WORK_DIR, use a cross-process project lock and append-only audit. Ambiguous solver outcomes stay unknown and block later writes rather than being reported as successful stops.

One periodic unit-cell solve, its S-parameter/R/T/A/PCR analysis, Floquet mode and incidence-angle readback, and selected exports passed local CST 2026.2 acceptance. Finite-array replication, circular-polarization switching, successful solver stopping, parameter sweeps and the patch-antenna recipe have not passed complete live acceptance. The last local stop experiment has an unresolved unknown job; do not treat its later CST SUCCESS as proof of a successful stop. See the public acceptance summary and metasurface status.

Related MCP server: cst-studio-mcp

Architecture

CLI / MCP stdio -> shared ToolSpec registry -> Service (schemas, audit, lock)
                                      -> core/session (single CST worker thread)
                                      -> fixed History / official CST Python API
                                      -> saved-results and workflow adapters

cst.interface is used from its original CST installation location; cst.results.ProjectFile(..., allow_interactive=False) reads saved data without starting CST. The CLI exposes a subset of the MCP tool catalog. See architecture for trust boundaries and lifecycle.

Install and run (Windows)

Requires Python 3.12, a licensed CST Studio Suite installation for live tools, and a compatible CST-provided Python library. The repository does not ship CST binaries, help files, or results. A conventional installation path is C:\Program Files\CST Studio Suite 2026; set CST_PATH for another location.

conda env create -f environment.yml
$env:CST_PATH = 'C:\Program Files\CST Studio Suite 2026'
$env:PYTHONPATH = "$env:CST_PATH\AMD64\python_cst_libraries"
$env:CST_WORK_DIR = Join-Path $HOME 'Documents\cst-rf-work'
conda run -n cst-rf-mcp cst-rf inspect status --json
conda run -n cst-rf-mcp cst-rf tools list --json

The public environment recipe defaults to manual connection and does not auto-launch CST. Set CST_WORK_DIR to a private writable folder before any mutation or solve. An existing conda environment may retain older environment variables: inspect it with conda env config vars list -n cst-rf-mcp before running; editing environment.yml does not reset an already activated process. Automatic launch/open/switch/popup handling is an explicit high-risk opt-in, not a safe installation default. Unknown dialogs are not clicked blindly. CST_TOOLSET currently does not filter tools and is not an authorization boundary; configure MCP client permissions separately. The MCP executable is cst-rf-mcp; do not expose all mutation and solver tools to untrusted agents.

Verify without CST

conda run -n cst-rf-mcp ruff check .
conda run -n cst-rf-mcp ruff format --check .
conda run -n cst-rf-mcp mypy src tests
conda run -n cst-rf-mcp pytest -m "not live and not solver"

GitHub Actions runs the same offline checks on Windows. Real CST acceptance requires separate opt-in and is never part of the default test suite. Reference code was not incorporated; see provenance and reference audit.

License

Apache-2.0; see LICENSE. This is an independent project and is not affiliated with or endorsed by Dassault Systèmes.