Is there a way we can add custom SCIM apis in IdentityIQ

I’d imagine it’s possible by creating your own JAXRS Servlet class which extends the base SCIM resource (sailpoint.rest.scim.SailPointSCIMRestApplication), and then registering your resource classes you would then subsequently write.

See the “Creating Custom Web Services” section of this whitepaper: Sign In to Compass - Compass

Rather than replacing the servlet entry mentioned, you would most likely replace this entry:

<init-param>
   <param-name>javax.ws.rs.Application</param-name>
   <param-value>sailpoint.rest.scim.SailPointSCIMRestApplication</param-value>
</init-param>