Deployment guide for administrators¶

This guide covers rolling out Model MCP to many Windows workstations. It has two parts: the add-in inside Revit and the Python server next to the MCP client. For a single machine, use requirements and installation.

Machine policy, the policy installer properties and the policy templates are described in the policy reference.

Choose an install scope¶

	SingleUser MSI	MultiUser MSI
File	`RevitModelMcp-<version>-SingleUser.msi`	`RevitModelMcp-<version>-MultiUser.msi`
Scope	Current user	All users on the machine
Administrator rights	Not needed	Needed
Add-in folder	`%APPDATA%\Autodesk\Revit\Addins\<year>`	`%ProgramData%\Autodesk\Revit\Addins\<year>` for Revit 2022 to 2026, `%ProgramFiles%\Autodesk\Revit\Addins\2027` for Revit 2027
Settings written by `UPDATECHECK=0`	`%LOCALAPPDATA%\RevitModelMcp\settings.json`	`%ProgramData%\RevitModelMcp\settings.json`
Automatic update	Downloads and installs the SingleUser MSI after Revit closes	Shows a notice only; an administrator updates the installation
Machine policy	Honored	Honored

The two installers are alternatives. Each refuses to install while the other scope is present, so uninstall one before installing the other. Use the MultiUser MSI for managed fleets: it needs no user rights at run time and it never self-updates.

The release builds are not Authenticode-signed yet. Revit shows its unsigned add-in prompt once per user, path and file content. See code signing and updates. A managed rollout therefore has to plan for that prompt, for example by signing the installed DLLs with your own organization certificate (install.ps1 -SignThumbprint does this for a developer install) and by using Revit's own trusted publisher mechanism. [INFERENCE] Where Revit stores the "Always Load" decision, and any administrator pre-trust, is not verified for this project.

Silent install¶

Run the installer with Revit closed. Use an elevated prompt for the MultiUser MSI.

msiexec /i RevitModelMcp-<version>-MultiUser.msi /qn /norestart /l*v "%TEMP%\rmm-install.log"

Switches and properties:

Item	Meaning
`/qn /norestart`	No user interface, no restart.
`/l*v <file>`	Verbose log. Attach it to a support request.
`UPDATECHECK=0`	Turn off the add-in update check. Writes `{"updateCheck":false}` to the settings file of the scope. Both MSIs.
`HTTP_ENABLED=1`	Reserve an HTTP URL for the optional loopback listener. MultiUser MSI only. Default `0`.
`HTTP_URL_PREFIX=<url>`	URL to reserve, default `http://127.0.0.1:53110/`. MultiUser MSI only.
`UPDATEMODE=off\\|notify\\|auto`	Update mode. Writes `updateMode` to the settings file of the scope, so it is below a machine policy `UpdateMode`. Both MSIs; `UPDATECHECK=0` is the legacy alias for `off`. See automatic updates.
`READONLY=1`	Refuse every action tool on this machine. Writes `ReadOnly=1` (DWORD) under `HKLM\Software\Policies\RevitModelMcp`. MultiUser MSI only.
`EXECUTECODE=off\\|confirm`	`off` refuses `revit_execute_code` and code in `revit_process_models`. Writes `ExecuteCode` to the same key. MultiUser MSI only.

See policy properties and Group Policy for how READONLY and EXECUTECODE behave on upgrade, repair and uninstall. ToolDeny, ToolAllow and the other policy values cannot be set through the MSI: use Group Policy, Intune or policy.json.

The MultiUser MSI also creates %ProgramData%\RevitModelMcp as SYSTEM with a protected ACL (Administrators and SYSTEM full control, Users read and execute) on every install, because that folder holds policy.json and settings.json. If the folder already exists as a link or is owned by someone other than Administrators or SYSTEM, the install stops before it changes anything. The verbose log (/l*v) has a line that starts with Model MCP: (copied from the check by the WiX quiet-exec action) and names the folder and the reason, and an interactive install shows the same text in a message box. The check exit codes are 20 (link or not a folder), 21 (wrong owner) and 22 (could not be checked). For a wrong owner run takeown /a /f "%ProgramData%\RevitModelMcp" in an elevated prompt (or delete the folder) and install again; for a link delete it. See the policy folder.

Example for a locked-down fleet:

msiexec /i RevitModelMcp-<version>-MultiUser.msi /qn /norestart ^
  UPDATEMODE=off READONLY=1 EXECUTECODE=off /l*v "%TEMP%\rmm-install.log"

The properties are public and secure, so a transform or a software distribution tool can set them.

Exit codes follow Windows Installer:

Code	Meaning
0	Success.
3010	Success, restart requested (not expected).
1603	Fatal error. Read the verbose log.
1638	A newer version is already installed. Downgrades are refused.

Upgrades within the same scope run in place, also for the same version. Repair with msiexec /fa <msi>. Uninstall with msiexec /x <msi> /qn. Uninstall leaves settings, logs and the channel folder; see data retention for the folders. MultiUser uninstall (not the removal step of an upgrade) also cleans %ProgramData%\RevitModelMcp: it deletes settings.json only when it holds nothing but the keys the MSI writes (updateCheck, updateMode), then deletes the folder only when it is empty. policy.json, any other file, a link or a folder with other content stays untouched, so an administrator's policy is never removed.

Policy properties and Group Policy¶

The installer treats HKLM\Software\Policies\RevitModelMcp as owned by Group Policy or Intune. It follows three rules:

It writes ReadOnly or ExecuteCode only when you set READONLY=1 or EXECUTECODE=off|confirm on the command line, or when an earlier run of the installer wrote that value. ReadOnly is always written as 1, so a repair can never write 0.
It remembers what it wrote in HKLM\Software\RevitModelMcp\MsiPolicy, not by reading the policy key. An upgrade, a repair (msiexec /fa) and Modify therefore keep the values without passing the properties again, and a value that Group Policy set is never rewritten, reset or deleted by the installer. A value on the command line always wins over the remembered one.
Uninstall removes only the values the installer wrote. To take a value back on an upgrade or a maintenance reinstall (msiexec /i <msi> REINSTALL=ALL REINSTALLMODE=vomus READONLY=0), pass READONLY=0 or EXECUTECODE=confirm. READONLY=0 removes the ReadOnly value the installer wrote (it never writes 0) in both cases, and only when the installer owns it: a value from Group Policy stays.

If Group Policy and the installer both write the same value, Group Policy refresh restores its own value. A broken or unreadable policy is never the result of an installer run: it fails closed, see unreadable policy.

Software distribution¶

SCCM or Configuration Manager¶

Create an application from the MultiUser MSI.
Install command: the msiexec line above. Uninstall command: msiexec /x <msi> /qn /norestart.
Detection rule: Windows Installer product code of the MSI, or the file RevitModelMcp.dll in the folder from the table above with a version equal to the package version.
Install behavior: system, whether or not a user is logged on. Add a requirement or a pre-install check that no Revit.exe is running, or accept that Revit loads the new files at its next start.
Return codes: treat 0 as success and 1638 as success if you deploy a version that is already newer.

Intune Win32 app¶

Wrap the MultiUser MSI with the Win32 Content Prep Tool into an .intunewin file.
Install and uninstall commands as above. Install behavior: system.
Detection rule: MSI product code, or the file rule on RevitModelMcp.dll.
Return codes: add 1638 as success if you stage newer versions first.
Assign to a device group, not a user group, because the MSI installs for all users.

Group Policy¶

Assign the MultiUser MSI as a computer software installation package in a GPO. Use a transform (.mst) to set the public properties. Deliver the machine policy values with a Registry preference item, see the policy reference. Environment variables for the Revit process, such as REVIT_MCP_NO_UPDATE_CHECK, can be set by a startup script, but registry or file policy is easier to audit.

WinGet¶

The package Sharafutdinov.RevitModelMcp is generated weekly for the latest stable release. For a managed fleet, prefer the MSI from your own software share so that you control the version.

Server rollout¶

The server is a Python package started by the MCP client through uv. The client machine needs Python 3.11 or newer, uv, and a way to fetch the package.

For a controlled fleet, pin the version and turn off the daily check:

claude mcp add revit-model-mcp -e REVIT_MCP_HOST=local -e REVIT_MCP_NO_UPDATE_CHECK=1 -- uvx revit-model-mcp==<version>

Use the same ==<version> pin in a JSON client configuration. The managed add-in bundle revit-model-mcp-<version>-managed.bundle.zip is built to never check for updates; see managed installs.

Offline or air-gapped install¶

The server does not need internet access once its packages are on the machine. Build a wheelhouse on a connected machine with the same Python version and platform, copy it to the offline site, and install from it:

# connected machine
python -m pip download revit-model-mcp==<version> -d wheelhouse

# offline machine
uv tool install --offline --no-index --find-links wheelhouse revit-model-mcp==<version>

Then register the installed command instead of uvx:

claude mcp add revit-model-mcp -e REVIT_MCP_HOST=local -e REVIT_MCP_NO_UPDATE_CHECK=1 -- revit-model-mcp

The repository also keeps a hash-pinned dependency list for the container image, server/requirements.docker.txt. You can use it as the seed for pip download --require-hashes. [INFERENCE] The exact uv flags above follow the uv documentation and have not been exercised on an air-gapped machine for this project. Test them in your environment first. The add-in needs no wheelhouse. To check an internal release mirror instead of GitHub, set REVIT_MCP_UPDATE_FEED; see updates.

Proxy and custom certificates¶

Component	Proxy behavior
Add-in update check	Uses the system proxy and the default Windows credentials.
Python server	Standard library proxy variables: `HTTP_PROXY`, `HTTPS_PROXY`, `NO_PROXY`.
uv package download	Follows uv settings. Typical variables are `HTTPS_PROXY`, `SSL_CERT_FILE`, `UV_NATIVE_TLS` and `UV_DEFAULT_INDEX` (see the uv documentation).

If you set HTTP_PROXY or HTTPS_PROXY for the server, also set NO_PROXY=127.0.0.1,localhost so that the loopback HTTP workstation host is not sent to the proxy. [INFERENCE] This follows Python's default proxy handling and is not covered by a project test. The complete list of outbound hosts is in the security whitepaper.

Multi-user and VDI hosts¶

The named pipe \\.\pipe\RevitModelMcp.<pid> is owned by the Windows user who runs Revit. A second user cannot open it.
Settings, the HTTP token and the channel folder live under %LOCALAPPDATA%\RevitModelMcp of each user. On non-persistent desktops they disappear with the profile unless the profile is kept.
The default HTTP port 53110 collides when several sessions run Revit on one host. Leave HTTP off, or give each session its own REVIT_MCP_HTTP_PORT.
Logs are written under Documents\RevitModelMcp\Logs. If your Documents folder is redirected to a cloud-synced location, logs with model names and paths sync with it. Redirect or exclude the folder, and see the LogDir policy value.

Verify the rollout¶

On a pilot machine, start Revit, open a model, and ask the client to call revit_ping. A success: true result means the add-in and the server are connected. Then check the effective settings: with the machine policy present, an action tool that policy blocks must return a result that starts with Blocked by organization policy:.