Introduction

Drut is a linter, formatter, and editor tooling suite for Cube Voyager control-statement scripts (.s / .block files) — the script language transportation planners use to write travel-demand model logic.

Editing these scripts without Drut usually means no syntax highlighting, no error checking until the model actually runs, and no consistent formatting across a team. Drut catches structural mistakes as you type, keeps scripts formatted consistently, and adds real editor support — syntax highlighting, hover help, autocomplete — to VS Code and any other editor that speaks the Language Server Protocol.

What Drut does

• Structural diagnostics — unmatched IF/LOOP/RUN/PROCESS blocks, unclosed comments, and other real mistakes, flagged before you run the model. See the Editor Guide for the full list.
• Formatting — consistent indentation and, optionally, keyword casing, operator spacing, and blank-line normalization — on save, on paste, or from the CLI. See the Formatter Guide.
• Hover, autocomplete, and “did you mean” spell-check for control words and keyword names.
• Shared project configuration via a drut.toml file, so a team doesn’t need to agree on CLI flags or editor settings individually. See the Configuration Reference.
• Three ways in: a drut CLI, a VS Code/Open VSX extension (built on the Language Server Protocol, so it works in any LSP-capable editor, not only VS Code), and a Model Context Protocol server for AI coding assistants — all built on one shared engine, so every surface agrees on what’s valid.

What Drut does not do

Drut is a structural and formatting tool, not a full semantic validator. It does not:

• Validate program-box-specific keyword combinations (e.g. whether a particular PATHLOAD parameter combination is meaningful for the model you’re running).
• Check cross-file/repo-wide semantics beyond the direct READ FILE inclusion hover already reaches.
• Run or simulate your model in any way.

These are explicit, current scope boundaries — not oversights.

Who this is for

Anyone writing or reviewing Cube Voyager .s/.block scripts: transportation model developers, analysts maintaining a shared script library, and teams that want consistent formatting without hand-enforcing a style guide.

Where to go next

• New to Drut? Start with Install, then Getting Started.
• Looking for a specific drut.toml field? Jump straight to the Configuration Reference.
• Integrating an AI coding assistant? See the MCP Guide.