S3 recording export works, but the Webchat transcript export via Lambda Data Action fails. CloudWatch hits a timeout at 3 seconds. The Lambda function’s timeout is set to 5s, but it’s still failing. Is the Genesys endpoint throttling the callback? Tried bumping the timeout in the flow, response never hits complete.
Type: AWS::Lambda::Function
Properties:
Timeout: 5
The timeout occurs because GC’s Data Actions enforce a strict 3-second sync limit. It doesn’t inherit your Lambda setting.
CXone Studio REST calls allowed 10 seconds, but GC’s Architect caps sync callbacks at 3s. Map the return payload to async pattern instead. Return presigned S3 URL instead of full transcript blob.
The 3-second sync cap is a hard limit in Architect, so bumping the Lambda timeout won’t actually change anything. The system drops the callback the moment that window closes, which acts exactly like an oversized HTML template choking an auto-routing rule. Switching to the async pattern with a presigned URL bypasses the payload size limit entirely. You’ll want to map the return object to just the URL and let the client handle the fetch.
Thanks for the tip, swapping to the async callback definitely clears up the timeout errors. The same thing happens when parsing email headers or stripping signatures from canned responses, where the JSON blob gets too heavy for the sync parser. Sorry for the newbie question here, but the terminology keeps getting mixed up between data actions and canned response triggers. Just drop the transcript into S3 first and pass the link back to the flow. The response hits complete without a hitch. Bucket permissions usually trip people up next.
Switching to async fixes this. The Architect documentation makes zero mention of that hard three-second sync cap, which is classic. You’ll need to set async: true in the request body to the Data Action. The /api/v2/webchat/conversations/{id}/transcripts endpoint supports this, but the parameters are buried in a PDF from 2021 that nobody links to anymore. Otherwise, the system waits for the blob and times out.
Make sure the Lambda returns a 200 immediately after generating the URL, or Architect hangs up. The return object should contain just the URL:
{
"status": "success",
"transcriptUrl": "https://s3-eu-central-1..."
}
Legacy flows trying to push 50KB strings hit this wall. The callback dies every time.
[Screenshot: Architect Data Action config showing return mapping]
One gotcha: the S3 bucket policy must allow the client’s IP range, or you’ll get 403s on the fetch.
The async toggle handles the payload size, but there’s a catch with how Architect processes the callback queue. When the flag flips to true, the platform stops waiting for the response, but it still enforces a strict rate limit on the webhook endpoint. If webchat traffic spikes, the callback queue backs up and you’ll see events drop silently. Watch the retry window closely. The system only attempts three retries before marking the action failed.
Here’s the payload structure that keeps the flow stable under load:
{
"async": true,
"callback_url": "https://your-lambda-url.execute-api.eu-central-1.amazonaws.com/prod/",
"payload": { "conversationId": "{{conv.id}}", "exportFormat": "json" }
}
Configure the Lambda to return a 202 Accepted immediately after queueing the export job. The flow continues, and the webhook fires once the S3 presigned URL is ready. This setup stalls when the callback URL lacks the trailing slash. Easy to miss. Add it. The queue handles the rest.