Architect Data Action: 403 Forbidden calling Lambda from Genesys Cloud

Architect & Flows
1

Hey everyone,

I’m trying to get a simple integration working where a Genesys Cloud Architect flow calls an AWS Lambda function via a Data Action. The goal is to push some adherence metrics to our internal database, but I’m hitting a wall with the IAM permissions.

I’ve set up the Lambda with a basic Node.js handler that just logs the input and returns a success message. On the Genesys Cloud side, I have a Data Action configured to make a POST request to the Lambda’s Invoke URL. I’m using the application/json content type and passing a simple JSON body with the agent ID and timestamp.

The problem is that every time the Data Action executes, it returns a 403 Forbidden error. The response body from AWS is pretty clear:

{
 "message": "User: arn:aws:sts::123456789012:assumed-role/GenesysCloudLambdaRole/i-0123456789abcdef is not authorized to perform: lambda:InvokeFunction on resource: arn:aws:lambda:us-east-1:123456789012:function:AdherenceTracker because no identity-based policy allows the lambda:InvokeFunction action"
}

I’ve checked the IAM role attached to the Lambda function, and it seems correct. Here’s the trust policy I’m using for the role:

{
 "Version": "2012-10-17",
 "Statement": [
 {
 "Effect": "Allow",
 "Principal": {
 "Service": "lambda.amazonaws.com"
 },
 "Action": "sts:AssumeRole"
 }
 ]
}

And the permissions policy attached to the role includes lambda:InvokeFunction on the specific function ARN. I even tried adding a resource-based policy to the Lambda function itself to allow arn:aws:iam::123456789012:root to invoke it, but that didn’t help either.

I’m pretty sure the issue is with how Genesys Cloud is authenticating the request or how the IAM role is being assumed. I’ve been staring at the AWS docs for hours, but I can’t figure out what’s missing.

Has anyone successfully set up a Lambda invocation from a Genesys Cloud Data Action? What IAM configuration did you use? I’m feeling pretty stuck here.

2

You’re probably missing the lambda:InvokeFunction permission on the resource policy, or your Genesys outbound IP isn’t whitelisted if you’re using a VPC endpoint. Since I manage these infra bits via Terraform, here’s how I usually lock this down. You need to attach a specific IAM role to the Lambda that allows the invocation.

resource "aws_lambda_permission" "genesys_invoke" {
 statement_id = "AllowExecutionFromGenesys"
 action = "lambda:InvokeFunction"
 function_name = aws_lambda_function.adherence_metrics.function_name
 principal = "apigateway.amazonaws.com" # Or specific IP if direct
 source_arn = "arn:aws:execute-api:${var.aws_region}:${var.aws_account_id}:${var.api_gateway_id}/*/*/invoke/functions/${aws_lambda_function.adherence_metrics.function_name}"
}

If you’re hitting the Invoke URL directly from Architect, make sure you’re using the authenticated endpoint, not the public one, unless you’ve explicitly opened it up (which is a bad idea). Check the CloudWatch logs for the Lambda; if it’s a 403, it’s almost always an IAM policy mismatch or a missing x-api-key if you’ve got API Gateway in front of it. Double check your request headers in the Data Action config too.