For a video example of what appears to be happening please see: https://www.loom.com/share/8d8df166170c42c0b1215ed167027df1

From what has been found it appears that a content selected LTI 1.3 activity can produce an exception from the "provisioning mode" variable being null.

"Exception - auth_plugin_lti::complete_login(): Argument #3 ($provisioningmode) must be of type int, null given, called in [dirroot]/enrol/lti/launch.php on line 108"

It appears to be that the provisioningmodelearner and provisioningmodeinstructor fields in mdl_enrol_lti_tools are set to NULL by default and do not appear to be getting programmatically updated, which with the default being NULL is what we assume is meant to be happen. This leads to the error described as provisioning mode refers to those.

Changing the provisioningmodelearner and provisioningmodeinstructor fields in the database for the existing LTI tools appears to resolve the issue or at the least stop the error from occurring.

Steps to reproduce:

Configure a LTI 1.3 external tool

Add this tool to a course as an activity using the external tool activity

Attempt to access the external tool after its creation as normal via the course page.

We expect:

To progress to the given LTI activity

What happens:

We receive the error "Exception - auth_plugin_lti::complete_login(): Argument #3 ($provisioningmode) must be of type int, null given, called in [dirroot]/enrol/lti/launch.php on line 108"

Let us know if you need anything else from us.