ObjectARX Wizard Skill — AutoCAD 2027 / VS 2026

Scaffold ObjectARX C++ projects and classes using an AI conversation + PowerShell generator.

Skill Location

The scripts live in the same folder as this SKILL.md:

<skill-root>/
├── SKILL.md
├── docs/
│   ├── arx-dev-guide.md              ← ObjectARX 2027 build configuration reference
│   └── learnings.md                  ← live wiki: gotchas, workarounds, verified API behaviors
├── scripts/
│   ├── Invoke-TemplateExpansion.ps1   ← shared token engine (do not call directly)
│   ├── New-ArxApp.ps1                 ← full ARX/DBX/CRX project
│   ├── New-ArxCustomObject.ps1        ← custom ObjectDBX entity class
│   ├── New-ArxReactors.ps1            ← transient reactor class
│   ├── New-ArxJig.ps1                 ← AcEdJig subclass
│   ├── New-ArxMFCSupport.ps1          ← MFC dialog / palette / control
│   ├── New-ArxNETWrapper.ps1          ← managed .NET wrapper
│   ├── New-ArxComWrapper.ps1          ← ATL COM wrapper object
│   └── New-ArxDynProp.ps1             ← ATL dynamic property class
├── templates/                         ← source template files (do not edit)
└── props/                             ← Autodesk.arx-2027.props, crx.props

When to Use

• Developer wants to start a new AutoCAD 2027 ARX/DBX/CRX C++ project in VS 2026
• Developer wants to add a Jig, Reactor, Custom Object, or other class to an existing project
• The classic VS wizard (File → New → Project → ObjectARX) is broken (VS 2026 regression — see MS Developer Community #11071541)

Wizard Types

User says...	Script to run
"ARX app", "new plugin", "create project"	New-ArxApp.ps1
"custom object", "custom entity", "AcDbEntity subclass"	New-ArxCustomObject.ps1
"reactor", "database reactor", "entity reactor"	New-ArxReactors.ps1
"jig", "AcEdJig", "interactive input"	New-ArxJig.ps1
"MFC dialog", "palette", "dockbar", "MFC class"	New-ArxMFCSupport.ps1
".NET wrapper", "managed wrapper", "C++/CLI"	New-ArxNETWrapper.ps1
"COM wrapper", "ATL object", "IDispatch"	New-ArxComWrapper.ps1
"dynamic property", "AcDbDynBlockReference", "dynprop"	New-ArxDynProp.ps1

---

Procedure

Step 1 — Identify skill root

Resolve the absolute path to this SKILL.md's containing directory. All scripts are at: <skill-root>\scripts\

---

Step 2 — Identify wizard type

Map user intent to one of the 8 wizard types above. If unclear, ask:

"Which wizard do you need? New ARX/DBX/CRX project, or an add-on class (Jig, Reactor, Custom Object, MFC, .NET Wrapper, COM Wrapper, Dynamic Property)?"

---

Step 3 — Collect parameters

Ask only for mandatory parameters that are missing. Do not ask for optional ones unless the user mentions them.

New-ArxApp — full project

Parameter	Mandatory	Values	Ask if missing
-ProjectName	Yes	valid C++ identifier	"What is the project name?"
-OutputPath	Yes	folder path	"Where should the project be created?"
-AppType	No	arx / dbx / crx	Default: arx (ask if user is unsure)
-MfcMode	No	none / shared / ext	Default: none
-UseAtl	No	switch	Only ask if user mentions COM
-UseDotNet	No	switch	Only ask if user mentions .NET or CLR
-RdsPrefix	No	3-letter symbol	Default: Adk

New-ArxCustomObject — custom entity

Parameter	Mandatory	Default
-ClassName	Yes	—
-OutputPath	Yes	—
-BaseClass	No	AcDbEntity
-Protocols	No	2 (Object + Entity)
-ProjectName	No	MyProject

New-ArxReactors — reactor

Parameter	Mandatory	Notes
-ClassName	Yes	—
-ReactorType	Yes	See reactor type list below
-OutputPath	Yes	—
-ProjectName	No	MyProject

Common reactor types: AcDbDatabaseReactor, AcDbObjectReactor, AcDbEntityReactor, AcEdInputContextReactor, AcApDocManagerReactor, AcDbLayoutManagerReactor, AcDbAnnotationScaleReactor, AcDMMReactor

New-ArxJig — jig class

Parameter	Mandatory	Default
-ClassName	Yes	—
-OutputPath	Yes	—
-ObjectName	No	AcDbEntity
-NumberOfInputs	No	1
-ProjectName	No	MyProject

New-ArxMFCSupport — MFC class

Parameter	Mandatory	Default
-ClassName	Yes	—
-OutputPath	Yes	—
-MfcType	No	Dialog
-IddDialog	No	IDD_DIALOG1
-ProjectName	No	MyProject

MFC types: Dialog, ChildDialog, TabDialog, Palette, PaletteSet, DockControlBar, Control, FileDialog, FileNavDialog, FieldDialog, FieldFormatDialog, FieldOptionDialog

New-ArxNETWrapper — managed wrapper

Parameter	Mandatory	Default
-WrapperName	Yes	—
-OutputPath	Yes	—
-CustomObjectName	No	AcDbEntity
-CompanyNamespace	No	Autodesk
-ObjectNamespace	No	AutoCAD
-ManagedDerivation	No	Entity
-ProjectName	No	MyProject

New-ArxComWrapper — ATL COM wrapper

Parameter	Mandatory	Default
-ShortName	Yes	—
-OutputPath	Yes	—
-ConnectionPoints	No	switch
-InterfaceDual	No	switch
-ProjectName	No	MyProject

New-ArxDynProp — dynamic property

Parameter	Mandatory	Default
-ClassName	Yes	—
-OutputPath	Yes	—
-InterfaceName	No	derived from ClassName
-ConnectionPoints	No	switch
-ProjectName	No	MyProject

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Step 4 — Run the script

Run the appropriate script from <skill-root>\scripts\ in a PowerShell terminal.

Example for a full ARX project:

& powershell.exe -ExecutionPolicy Bypass -NoProfile -File "<skill-root>\scripts\New-ArxApp.ps1" `
    -ProjectName MyPlugin `
    -OutputPath  "C:\Dev" `
    -AppType     arx `
    -MfcMode     shared

Example for a Jig add-on:

& powershell.exe -ExecutionPolicy Bypass -NoProfile -File "<skill-root>\scripts\New-ArxJig.ps1" `
    -ClassName      CMyJig `
    -ObjectName     AcDbLine `
    -NumberOfInputs 2 `
    -ProjectName    MyPlugin `
    -OutputPath     "C:\Dev\MyPlugin"

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Step 5 — Confirm output

After the script runs, confirm what was generated by listing the output folder:

Get-ChildItem "C:\Dev\MyPlugin" | Select-Object Name, Length

Report the file list to the user and include next steps:

For New-ArxApp:

"Project created at C:\Dev\MyPlugin\MyPlugin.vcxproj. Open it in Visual Studio 2026. Verify the ObjectARX SDK path in Autodesk.arx-2027.props, then Build → x64 Debug."

For add-on wizards:

"Generated ClassName.h and ClassName.cpp in OutputPath. In Visual Studio: right-click your project → Add → Existing Item → select the files."

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Troubleshooting

Problem	Fix
Destination already exists	Choose a different -OutputPath, or delete the existing folder first
ReactorType not found	Run Get-ChildItem <skill-root>\templates\reactors\*_tmpl.h | ForEach-Object { $_.Name -replace '_tmpl\.h$','' } for the full list
Build error: Cannot open include file 'acdb.h'	Set ARXSDK env var or edit Autodesk.arx-2027.props to point at your ObjectARX 2027 SDK
CLRSupport errors in .NET wrapper	Ensure the project's .vcxproj has <CLRSupport>NetCore</CLRSupport>
VS 2026 wizard still broken	This skill replaces it — ignore the broken File→New wizard. Use this skill instead.

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Post-Scaffolding: Build Configuration Reference

After a project is scaffolded, the developer (or you, the AI agent) will continue writing plug-in code. When helping with build settings, library selection, preprocessor defines, or diagnosing linker/runtime errors, read <skill-root>/docs/arx-dev-guide.md. It covers:

• Required compiler flags (/MD, /EHsc, /GR, etc.) and why each matters
• The property-sheet inheritance chain (rxsdk_common → debug/release → dbx/arx/crx)
• Which .lib files to link for each project type (DBX, ARX, CRX) and optional APIs (B-Rep, AEC Modeler)
• Debug vs Release configuration differences
• Common pitfalls — especially the /MD vs /MDd rule (AutoCAD is always a Release binary; plug-ins must use /MD even in Debug)

Critical rule: AutoCAD ships as a Release build. Plug-in DLLs must always link with /MD (MultiThreadedDLL), never /MDd. Using /MDd causes CRT mismatch, heap corruption, and crashes. /MDd is only valid with an internal Autodesk Debug build of AutoCAD.

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Field Learnings

<skill-root>/docs/learnings.md is a living wiki of gotchas hit in real sessions: VS 2026 + MFC + ARX SDK 2027 build traps, DllMain conflicts, MFC module-state rules, scaffold quirks. Read it when:

• Diagnosing build / link errors that look like CRT / STL / RTC mismatches
• A scaffolded project fails on first build with MFC shared mode
• Adding new templates — promote any newly verified fix from learnings.md back into the template files in this skill so future scaffolds inherit the fix.