Use DescribeUserPoolClient with an AWS SDK or CLI

To describe a user pool client

This example describes a user pool client.

Command:

aws cognito-idp describe-user-pool-client --user-pool-id us-west-2_aaaaaaaaa --client-id 38fjsnc484p94kpqsnet7mpld0

Output:

{
  "UserPoolClient": {
      "UserPoolId": "us-west-2_aaaaaaaaa",
      "ClientName": "MyApp",
      "ClientId": "38fjsnc484p94kpqsnet7mpld0",
      "ClientSecret": "CLIENT_SECRET",
      "LastModifiedDate": 1548108676.163,
      "CreationDate": 1548108676.163,
      "RefreshTokenValidity": 30,
      "ReadAttributes": [
          "address",
          "birthdate",
          "custom:CustomAttr1",
          "custom:CustomAttr2",
          "email",
          "email_verified",
          "family_name",
          "gender",
          "given_name",
          "locale",
          "middle_name",
          "name",
          "nickname",
          "phone_number",
          "phone_number_verified",
          "picture",
          "preferred_username",
          "profile",
          "updated_at",
          "website",
          "zoneinfo"
      ],
      "WriteAttributes": [
          "address",
          "birthdate",
          "custom:CustomAttr1",
          "custom:CustomAttr2",
          "email",
          "family_name",
          "gender",
          "given_name",
          "locale",
          "middle_name",
          "name",
          "nickname",
          "phone_number",
          "picture",
          "preferred_username",
          "profile",
          "updated_at",
          "website",
          "zoneinfo"
      ],
      "ExplicitAuthFlows": [
          "ADMIN_NO_SRP_AUTH",
          "USER_PASSWORD_AUTH"
      ],
      "AllowedOAuthFlowsUserPoolClient": false
  }
}

    def describe_user_pool_client(
        self, user_pool_id: str, client_id: str
    ) -> dict[str, Any]:
        """
        Describes an app client in a user pool, including the client secret.

        :param user_pool_id: The ID of the user pool that contains the app client.
        :param client_id: The ID of the app client to describe.
        :return: A dictionary with the app client configuration.
        """
        try:
            response = self.cognito_idp_client.describe_user_pool_client(
                UserPoolId=user_pool_id, ClientId=client_id
            )
            client_info = response.get("UserPoolClient", dict())
            logger.info(
                "Described app client %s in user pool %s.",
                client_id,
                user_pool_id,
            )
            return client_info
        except ClientError as err:
            if err.response["Error"]["Code"] == "ResourceNotFoundException":
                logger.error(
                    "The user pool %s or client %s does not exist. "
                    "Verify the stack deployed successfully and the outputs are correct.",
                    user_pool_id,
                    client_id,
                )
            raise