Different input type and return type

[ppsirius]

I try to test
https://github.com/graphql-nexus/examples/tree/master/plugins-prisma-and-jwt-auth-and-shield
and saw that singup mutation have
type: 'AuthPayload',
When I try to type in playground this mutation with correct values like name, email and password I get error because type: 'AuthPayload', requried different values.
I think it's probably bug so I create new type
schema.objectType({ name: 'SingUpInput', definition(t) { t.string('name') t.string('email') t.string('password') }, })
but then on response get
"data": { "signup": { "name": null, "email": null, "password": null } } }

I can't find information about type and input in the documentation, so maybe someone could explain to me how to fix this?