Wrangler_ can use Read Only (RO) access for the source cluster for discovery
CUCM Access
Before starting the migration, the source and target CUCM, and if required CUC, interfaces must be defined. The minimum Required access roles in the CUCM Application User for the AXL interface are
Standard AXL API Access
Standard CCM Admin Users
Standard SERVICEABILITY Read Only
Standard AXL Read Only API Access
To enable Read-Only access select the ‘Standard AXL API Users’ and ‘Standard AXL Read Only API Access’ roles refer to https://developer.cisco.com/docs/axl/#!authentication/using-basic-authentication as both roles are arequired for RO access