IfcOpenShell API Module System

Quick Reference

ALWAYS use ifcopenshell.api.run() or direct module calls for IFC mutations. NEVER modify entity attributes directly (e.g., wall.Name = "X") — use api.run("attribute.edit_attributes", ...) instead.
ALWAYS import ifcopenshell.api before calling any API function. The module uses lazy loading; functions are NOT available without this import.
ALWAYS pass the file (model) object as the first positional argument after the function name in api.run().
NEVER invent API module or function names. There are exactly 35 modules — see the module table below. Hallucinated calls like api.run("element.create", ...) or api.run("wall.add", ...) do NOT exist.
ALWAYS use keyword arguments for all parameters after the model. Positional arguments beyond the model are NOT supported.
NEVER use model.create_entity() for production code. Use api.run("root.create_entity", ...) — it generates GlobalIds, sets ownership, and validates predefined types automatically.
ALWAYS set up a complete project before creating elements: IfcProject → units → contexts → spatial hierarchy. See the bootstrap pattern below.
NEVER assume products parameters accept single elements. Since IfcOpenShell v0.8+, most relationship functions expect products as a list, not a single entity.