Modules

A module is a pure algorithm you import and call. Unlike snaptrude.*, which is an asynchronous conversation with the running editor, a module is imported, synchronous, deterministic and never touches the scene: it takes plain data and returns plain data, and the caller does every read and every write around it.

Three doors

Door	How you reach it
A plugin worker	import { … } from "@snaptrude/plugin-toolkit/<export>"
The design agent's run_worker sandbox	modules.<group>.<name>.<fn>(…), already in scope
Node, a test, a script	the same npm package, no host needed

The unit rule

Every module input carries unit: "mm" | "cm" | "m" | "ft" | "in". Every length in that call is read and written in it — 30 stays 30 — and the output echoes the unit. Angles are degrees; areas are the unit squared. The modules' own defaults and tolerances are defined in millimetres and scaled to the unit, so they mean the same thing everywhere. Pass the project's unit and never convert a value yourself.

In scope in a worker body

The design agent's run_worker body sees three objects, all documented here:

Object	What it is
modules.<group>.<name>	the pure modules below, synchronous
inputs.last(module) / inputs.at(id)	the input of an earlier traced module call, byte-identical — run.inputs
kept.<name>	values an earlier body returned under keep: {…} — run.inputs

Build a module input once per chat; every later body is { ...inputs.last(m), field: value }.

Modules

Module	Import	What it does
pack.bubbleLayout	@snaptrude/plugin-toolkit/pack-bubble-layout	Arrange sized bubbles so that wished-for neighbours end up near each other and nothing overlaps.
pack.corridorBand	@snaptrude/plugin-toolkit/pack-corridor-band	Reserve a strip along a centreline and carve it out of the regions you are about to pack.
pack.corridorRuns	@snaptrude/plugin-toolkit/pack-corridor-runs	Lay typed cells along corridor paths.
pack.footprintPlacement	@snaptrude/plugin-toolkit/pack-footprint-placement	Seat footprints inside a boundary.
pack.linearArray	@snaptrude/plugin-toolkit/pack-linear-array	Fit items of known width along aligned segments.
pack.rooms	@snaptrude/plugin-toolkit/pack-rooms	Subdivide a boundary into one cell per room, areas proportional to targets, and return N ranked candidates.
geom.circlePacking	@snaptrude/plugin-toolkit/geom-circle-packing	Circle packing primitives: keep a set of plan circles from overlapping, and keep them inside a ring.
geom.polygonBoolean	@snaptrude/plugin-toolkit/geom-polygon-boolean	Plan-polygon booleans and offsetting: set operations on regions with holes, stroking a centreline into a band, and the per-edge mitre inset a setback is.
geom.polygon	@snaptrude/plugin-toolkit/geom-polygon	The plan-polygon primitives every pack module shares: area and winding, centroid, bounding boxes, containment, distance, segment and ring intersection, ring simplicity, convex hull, minimum-width strip (OBB), shared-edge length, transforms, convex-window clipping, SAT separation and hole bridging.
geom.polylineFrame	@snaptrude/plugin-toolkit/geom-polyline-frame	Arc-length frame along a plan polyline.
run.inputs	@snaptrude/plugin-toolkit/run-inputs	What a worker body can carry over from earlier bodies.