Protocol
The Model Context Protocol (MCP) is a standard way for an AI client to discover and use capabilities exposed by a local server. RevitDevTool uses the protocol to connect an AI client to running Revit or AutoCAD-family hosts.
Official SDKs
RevitDevTool pins the SDK versions used by its two toolset entry points:
| SDK | Pinned version | Official documentation |
|---|---|---|
| .NET SDK | 2.2.0 | C# SDK Getting Started · C# SDK repository |
| Python SDK | 2.1.1 | Python SDK documentation · Python SDK repository |
For the protocol itself, see the official MCP specification.
Core concepts
| MCP concept | Meaning |
|---|---|
| Client | The AI application, such as Cursor, Claude Desktop, VS Code Copilot, or ChatGPT Desktop |
| Server | The local RevitDevTool MCP service that connects the client to hosts |
| Tool | An operation the client can call, such as querying a model or opening a document |
| Resource | Readable context identified by a URI, such as model state or an API cheatsheet |
| Prompt | A reusable instruction template exposed to the client |
The normal user-facing flow is: connect the client, choose a running host, search the available capabilities, invoke a tool or read a resource, then inspect the result.
RevitDevTool default tools
These capabilities are available from the local MCP service or from a connected host:
| Tool | Purpose |
|---|---|
list_host_instances | Show running Revit and AutoCAD-family instances |
launch_host | Start a supported host instance |
read_file_info | Read metadata and a safe summary for a local file |
list_machines | List available local machine targets |
search_dynamic | Find tools and resources available on a connected host |
invoke_dynamic | Invoke a discovered capability |
execute_csharp_code | Run C# code in the host context |
execute_python_code | Run Python code in the host context |
open_document | Open a document in the host |
navigate_history | Move backward or forward through supported model changes |
view_screenshot | Capture the current host view for visual inspection |
The exact host-specific entries depend on which host is running and which optional toolsets are registered.
Default resources
RevitDevTool provides host reference and context resources. The available set depends on the connected host:
| Host | Resource URI | Purpose |
|---|---|---|
| Revit | revit://python-cheatsheet | Revit Python usage guidance |
| Revit | revit://csharp-cheatsheet | Revit C# usage guidance |
| Revit | revit://model/context | Current model context and summary |
| Revit | revit://model/warnings | Current model warnings |
| Revit | revit://version | Host and API version information |
| AutoCAD-family | acad://python-cheatsheet | AutoCAD Python usage guidance |
| AutoCAD-family | acad://csharp-cheatsheet | AutoCAD C# usage guidance |
These resources are read-only context. Registered .NET or Python toolsets may add additional tools and resources for their own domain.
Default prompts
The local service exposes:
revit_codefor Revit code-generation guidance;acad_codefor AutoCAD-family code-generation guidance.
.NET and Python toolsets
RevitDevTool accepts both compiled .NET assemblies and Python toolset folders containing a *mcp.py entry file. The entry file carries its own PEP 723 dependency metadata; its capabilities appear alongside the defaults when the relevant host is running.
Use MCP .NET or MCP Python for registration guidance.