ServiceNow Data Action failing with 400 Bad Request on Genesys Cloud Webhook Payload

Anyone know why the ServiceNow REST API endpoint /api/now/table/incident is rejecting the webhook payload from Genesys Cloud with a 400 Bad Request error, specifically citing an invalid field format for the caller_id parameter?

The environment is running the latest Genesys Cloud release in the EU-West region. The Data Action is configured to trigger on conversation_start for web chat channels. The JSON payload structure matches the schema defined in the ServiceNow REST API documentation, including the required fields like short_description and description. However, the caller_id field, which contains the email address from the chat session, seems to be causing the issue. The ServiceNow table expects a string format, but the error response suggests a mismatch in the expected data type or encoding.

The webhook configuration in Genesys Cloud is set to send the full event payload. I have verified the basic authentication credentials and the endpoint URL. The issue persists across multiple test runs. The error message from ServiceNow is: “Field caller_id is not a valid value for this field.” This suggests that the value being passed might be null or improperly formatted, even though the chat session clearly captures the user’s email address.

Has anyone encountered a similar issue with Data Actions and ServiceNow integration? Any insights on how to debug the payload transformation within the Genesys Cloud Data Action before it reaches ServiceNow would be appreciated.

If I remember correctly, this often stems from SIP header normalization clashing with ServiceNow’s strict integer parsing for phone fields. Try mapping conversation.participants[0].user.phone_number instead of caller_id, ensuring the output is a clean E.164 string without leading plus signs or formatting characters that trigger the 400 error on the target endpoint.

Oh, this is a known issue…

Cause:
ServiceNow’s REST API expects strict data types for fields like caller_id, but Genesys Cloud webhooks often send this as a string with formatting or null values during conversation_start. In Zendesk, we handled this by pre-validating fields in the ticket creation script before hitting the API. Genesys Cloud does not enforce this validation on outgoing webhooks by default, leading to 400 errors when the target system rejects malformed JSON.

Solution:
Instead of sending the raw caller_id, use a Data Action to transform the payload before sending it to ServiceNow. Create a new Data Action that maps conversation.participants[0].user.phone_number to a new field, ensuring it is stripped of non-numeric characters. Then, in your ServiceNow integration, reference this transformed field. This mirrors the “clean data” approach we used in Zendesk macros. Also, verify that the ServiceNow endpoint allows CORS if testing from a browser, though this is likely a payload format issue.

This seems like a classic data type mismatch issue in the data action configuration. the previous suggestion about phone numbers is relevant for voice, but for web chat conversation_start, the caller_id usually maps to the participant’s user object or external id, which serviceNow expects as a specific sys_id format (string) or a link to the cmdb person table. if you are sending a raw json object or null, serviceNow returns 400.

you need to explicitly cast the value in the data action. do not just pass participant.user.id. use an architect expression to ensure it is a string. if the field is optional, use a default empty string to avoid null rejection.

here is the expression you should use in the data action field mapping for caller_id:

${!participant.user.id != null ? participant.user.id : ""}

also, check the short_description and description fields. serviceNow often rejects requests if these are empty or exceed 255 characters. use this to sanitize the description:

${!substr(participant.initial_message.text, 0, 250)}

ensure your data action method is POST and the header Content-Type is set to application/json. if you are using the purecloud sdk for debugging, use platformClient.conversations.getConversationDetail to inspect the raw participant attributes before the data action triggers. this helps verify if participant.user exists at conversation_start or if you need to wait for conversation_update.

in my experience with inbound message flows, the conversation_start event sometimes fires before the user object is fully populated in the participant list. if the 400 persists, change the trigger event to conversation_update and add a condition participant.user.id != null. this ensures the lookup has resolved.

also, verify the oauth scope if you are using an api key for the data action. it needs conversation:read and user:read. if the scope is wrong, you might get a 401, but if the payload structure is invalid, it is 400. double check the json structure against the serviceNow table schema.

{
 "caller_id": "${!participant.user.id != null ? participant.user.id : ''}",
 "short_description": "${!participant.initial_message.text}",
 "description": "${!substr(participant.initial_message.text, 0, 250)}"
}

this should resolve the bad request error.

{
“caller_id”: “ext:{{conversation.participants[0].user.external_id}}”
}

You might want to look at mapping the external_id directly. ServiceNow requires a valid sys_id or external identifier string for caller_id. Sending a complex user object causes the 400 error. Verify the payload structure in the CXone Data Action logs before hitting the endpoint.