Authenticate AppSync queries console with Cognito User Pools - amazon-cognito

Question

I am trying to authenticate Queries playground in AWS AppSync console. I have created User Pool and linked it to the AppSync API, I have also created an App Client in Cognito User Pool (deployed using CloudFormation). It appears under Select the authorization provider to use for running queries on this page: in the console.
When I run test query I get:
{
"errors": [
{
"errorType": "UnauthorizedException",
"message": "Unable to parse JWT token."
}
]
}
This is what I would expect. There is an option to Login with User Pools. The issue is I can't select any Client ID and when I choose to insert Client ID manually, anything I enter I get Invalid UserPoolId format. I am trying to copy Pool ID from User Pool General settings (format eu-west-2_xxxxxxxxx) but no joy. Btw, I am not using Amplify and I have not configured any Identity Pools.
EDIT:
Here is the CloudFormation GraphQLApi definition:
MyApi:
Type: AWS::AppSync::GraphQLApi
Properties:
Name: !Sub "${AWS::StackName}-api"
AuthenticationType: AMAZON_COGNITO_USER_POOLS
UserPoolConfig:
UserPoolId: !Ref UserPoolClient
AwsRegion: !Sub ${AWS::Region}
DefaultAction: ALLOW

Answer 1

To set up the stack using CloudFormation I have followed these 2 examples:
https://adrianhall.github.io/cloud/2018/04/17/deploy-an-aws-appsync-graphql-api-with-cloudformation/
https://gist.github.com/adrianhall/f330a10451f05a529680f32978dddb64
Turns out they both (same author) have an issue in them in the section where ApiGraphQL is defined. This:
MyApi:
Type: AWS::AppSync::GraphQLApi
Properties:
Name: !Sub "${AWS::StackName}-api"
AuthenticationType: AMAZON_COGNITO_USER_POOLS
UserPoolConfig:
UserPoolId: !Ref UserPoolClient
AwsRegion: !Sub ${AWS::Region}
DefaultAction: ALLOW
Should be:
MyApi:
Type: AWS::AppSync::GraphQLApi
Properties:
Name: !Sub "${AWS::StackName}-api"
AuthenticationType: AMAZON_COGNITO_USER_POOLS
UserPoolConfig:
UserPoolId: !Ref UserPool
AwsRegion: !Sub ${AWS::Region}
DefaultAction: ALLOW
Thank you #Myz for pointing me back to review the whole CF yaml file