What is a Revit AI Assistant?
A Revit AI assistant is an agent that lives inside Autodesk Revit and turns plain-language requests into actions on the model. AllAddin (two L's, not Disney's Aladdin) is one such assistant - one of a small handful in 2026.
What it does, concretely
A Revit AI assistant takes a request like "count all walls by level" or "tag every door on this sheet with its fire rating" and produces either a result, a script that produces the result, or an automated action inside the active Revit document. The defining feature is the host: the assistant runs inside Revit, with access to the live model, not in a separate browser or IDE.
What separates a Revit AI assistant from a generic LLM
Generic LLMs (ChatGPT, Claude, Copilot, Cursor)
Understand language and produce text. They can describe how the Revit API works in the abstract and write code that LOOKS like Revit-API code. They cannot run the code inside Revit, cannot observe the result, and cannot iterate on a failure. Version differences between Revit 2024 vs 2025 vs 2026 vs 2027 are outside their context unless you supply that context every turn.
A Revit AI assistant
Lives inside Revit. Knows which Revit version is running, which document is active, what's selected, what view is open. Generates code targeted at that exact environment, runs it inside a Revit transaction, and reports what changed. If it fails, it can retry with a different approach because it has the failure ledger from previous attempts.
What separates a Revit AI assistant from a macro tool
Macro / scripting tools (Dynamo, pyRevit)
Both require you to write or wire up code yourself. Dynamo gives you a visual programming canvas; pyRevit gives you a Python scripting host. Both ship with libraries and example scripts. You still need to know what to write, or which node to drag in, or which existing button to click.
A Revit AI assistant
Generates the code on demand from plain language. You say what you want; the assistant writes and runs the code. You do not need to know the Revit API. Dynamo and pyRevit remain useful tools, but the AI assistant is the layer ABOVE them - it can write a pyRevit script for you if that is the right output, or it can run code directly in the live model.
The Revit AI assistants in 2026
Three products fit the definition of "Revit AI assistant" at the time of writing:
- AllAddin - this product. Multi-version (Revit 2025, 2026, 2027). IronPython 3.4 + C#. Independent of Autodesk accounts. Made by MeliUX Ltd in the UK.
- Autodesk Revit AI Assistant - built by Autodesk, ships with Revit 2027 only. Uses whitelisted pre-built functions rather than arbitrary code execution. See the side-by-side comparison.
- Conduit (e-verse) - in private beta. Generates ephemeral ribbon code; no execution ledger documented at time of writing.
How to choose between them
Version coverage is the first filter. If you run anything earlier than Revit 2027, Autodesk's tool is not an option. If you need arbitrary code (not just whitelisted functions), Autodesk's tool is not an option for that either. AllAddin runs on Revit 2025 onwards and generates both IronPython and C#.
Trust is the second filter. AllAddin's trust posture details what leaves the machine, what stays local, sandboxing, and the legal entity behind the tool.