Server
Here you will find the MCP Server settings that run in Cinema 4D. A connection to MCP Clients can only be established if an MCP Server is running.
The MCP Server is initialised through Python when Cinema 4D starts. Security software that monitors Python — antivirus or endpoint protection programs, for example — can interfere with this step. Cinema 4D then starts as usual, but the MCP page is missing from the Preferences, even though nothing is wrong with the installation. This has been observed with one endpoint protection product, and other programs of this kind may behave in the same way. If the MCP page does not appear, check whether your security software blocks Python in Cinema 4D, and have an exception added where necessary — on a managed computer, usually by your IT department.
Select this option to start the MCP Server, which can then be used to connect to selected MCP Clients.
If, for security reasons, you want to turn the MCP server on and off at specific times while you work, the Start MCP Server and Stop MCP Server commands are available under the entry in the menu of Cinema 4D.
These commands have the same effect, so this would be equivalent to turning the Allow MCP Server option on and off here in Preferences.
This setting is only available if the Allow Remote Connections option is enabled. This enables Cinema 4D and its MCP Server to communicate with the MCP Client on another computer or network. This comes with additional security risks, as the remote connection is unencrypted. Therefore, you should only enable such a remote connection to networks you trust.
The Host ID is the unique identification number of your system that is to be accessed from outside. The remote client uses this ID to locate the correct computer and establish the connection.
In such cases, set the Host ID to an address that is visible from the connected network.
These settings generally do not need to be changed, unless the default port is blocked on your end or is already reserved for other services.
The MCP Server is using this token to authenticate the MCP Client.
Do not share this token with others, as it could potentially be used to gain access to your computer. The token is stored in a separate preferences file. Depending on the client, the MCP Client configuration file either points to that file or contains a copy of the token itself; in both cases, the token is stored only on your computer. If you suspect that you may have accidentally shared the token—for example, through a screenshot—change it here. You will then need to restart the MCP Client so that it can read the updated token. Clients whose configuration contains a copy of the token must first be written again with Update Selected Client on the Clients page. Be sure to also terminate all MCP Client’s background processes when you exit the application.
Show Token
By default, only the last few characters of the authentication key are visible for security reasons. You should enable this option only if you want to view the entire key. Otherwise, to make it more difficult to inadvertently share the Auth Token, you should leave this option disabled.
Copy Token
This copies your Auth Token to the clipboard in case you want to save it separately. In general, be careful not to inadvertently share this token with others, as this could allow external access to Cinema 4D and—through the use of Python—to your entire computer.
Regenerate Token
If you're unsure whether you've accidentally shared your Auth Token with others, for example, you should generate a new one right away. You can do this either by entering your own Auth Token (activate Show Token for full access) or by clicking this button. In that case, a new string will be generated at random and will immediately replace the old token. What this means for the connected MCP Clients depends on how their configuration carries the token. A client whose configuration only points to the token file picks up the new token the next time it is restarted. A client whose configuration contains a copy of the token stops working until it is selected on the Clients page and written again with Update Selected Client.
Here, you define a time interval. If a client does not respond within this time interval after being prompted by the server, a corresponding error message is generated. The default time period should be sufficient in most cases.