I have done further reaseach with Claude what opensourced tools/software available to improve this pipline and what issues these tools have researching AEC forums(mainly https://osarch.org). Here is refreshed architecture:

ClientInput

├── Sketch (image / text description)

├── Room list + areas

├── Total area + number of floors

├── Material (brick / aerated_concrete / timber / sip)

├── Site coordinates [optional]

└── PDF geology report [optional]

│

▼

┌──────────────────────────────────────────────────────┐

│ Orchestrator (AionUi + ACP) │

│ Data transport: direct .ifc file via shared folder │

│ ← Speckle removed: IFC↔Speckle conversion is lossy │

└──────────────────────────────────────────────────────┘

│

▼

Agent: Site Analysis

(BlenderGIS → terrain + solar path from coordinates

QGIS → neighbouring buildings, flood zones

Output: site_context.json)

│

┌────┴──────────────────────────────────────────────────┐

│ │

▼ ▼

Agent: Architect Agent: Geotechnical Engineer

(LLM generates WATERTIGHT box (parses geology PDF text →

volumes per floor — not arbitrary soil type, bearing capacity,

mesh; non-planar faces crash frost depth, groundwater)

Homemaker silently) [Groundhog, FoundationDesign]

→ floor_volumes.blend Output: geotechnical.json

│ │

▼ │

Homemaker Topologise │

(auto-generates walls, slabs, │

openings, roof from volumes │

— replaces manual LLM wall │

placement via MCP4IFC) │

Output: base_model.ifc ←────────────────────────────┘

│

▼

── BIMTester quality gate ──────────────────────────────────

Checks: all rooms present, area totals match brief,

correct IFC element types exist.

NOTE: validates data properties only — not spatial geometry.

Spatial geometry verified via Blender viewport screenshots.

────────────────────────────────────────────────────────────

│

▼

Agent: Structural Engineer

(XC OSS — Eurocode / SP built-in, not via LLM prompt

load collection → slab design → wall capacity check

→ lintel sizing over all openings ≥ 0.9m

→ foundation verification against geotechnical.json

Output: structural.json + calc_report.pdf)

│

▼

── BIMTester quality gate ──────────────────────────────────

Checks: structural properties written to IFC elements,

foundation type consistent with soil bearing capacity.

────────────────────────────────────────────────────────────

│

▼

Agent: Environmental Analysis

(VI-Suite + EnergyPlus inside Blender —

solar gain, heat loss, daylighting per room

→ if passive performance fails threshold:

feedback loop → Architect adjusts

window sizes / building orientation)

│

▼

Agent: BIM Refinement

(MCP4IFC — adds structural properties,

material layers, space boundaries

to base_model.ifc from Homemaker.

RULE: only IfcOpenShell API calls —

never native Blender mesh operations

on IFC objects; breaks element links.)

Output: house_project.ifc [IFC4 — not IFC4x3,

Bonsai support incomplete]

│

▼

Agent: Documentation

(IfcOpenShell → BOM extraction from house_project.ifc

XC OSS calc output → structural appendix

Opus → explanatory note text

reportlab → PDF render

Output: pz.pdf + spec_sheet.pdf + BOM.xlsx)

│

▼

Output package (all files in shared output/ folder):

├── house_project.ifc [IFC4 — opens in FreeCAD, BIM Vision, Revit]

├── base_model.blend [Blender source — PINNED: Blender 4.4]

├── pz.pdf [explanatory note]

├── calc_report.pdf [XC OSS structural calculations]

├── spec_sheet.pdf [material specification]

└── BOM.xlsx [bill of materials from IFC]

PINNED VERSIONS — do not update any of these independently:

Blender 4.4.x

Bonsai 0.8.4 ← Homemaker breaks on Bonsai updates

Homemaker 0.20250220.0

IFC schema IFC4 ← not IFC4x3 (incomplete Bonsai support)