### Answer The best approach is to create a custom post-call analysis field to detect spam calls. Here's how: ## Set Up a Custom Analysis Category Post-call analysis supports several data types you can use for spam detection [(1) ]() : - Boolean (True/False) – Create a field like

is_spam

that returns true/false based on conversation patterns - Selector (Enum) – Create a field with categories like "spam", "legitimate", "unknown" - Text (String) – Extract details about why a call might be spam ## Consume via Webhook When the

call_analyzed

webhook fires, the payload includes the

call_analysis

object [(2) ]() [(3) ]() :

json
{
  "event_type": "call_analyzed",
  "call": {
    // Call object with call_analysis field populated
  }
}

[(2) ]() The

call_analysis

object contains your custom fields in

custom_analysis_data

[(4) ]() :

json
"call_analysis": {
  "call_summary": "...",
  "in_voicemail": false,
  "user_sentiment": "Positive",
  "call_successful": true,
  "custom_analysis_data": {}
}

## Important Notes - Post-call analysis fields will not be populated for calls that were not connected or where no conversation took place—check whether the field exists before using it [(2) ]() [(1) ]() - If a call doesn't connect (e.g.,

dial_no_answer

) , no meaningful analysis will occur [(5) ]() Define your spam detection criteria in the custom analysis settings (e.g., short call duration, no meaningful conversation, specific keywords) , and then check the

custom_analysis_data

field in the webhook payload.

​ To learn more, see the sources I considered: [[1] Post Call Analysis Overview](https://docs.retellai.com/features/post-call-analysis-overview) [[2] Consume the analysis data](https://docs.retellai.com/features/post-call-analysis-consumption) [[3] Webhook Overview](https://docs.retellai.com/features/webhook-overview) [[4] Get Call](https://docs.retellai.com/api-references/get-call) [[5] No "call_analyzed" webhook for some disconnection reasons](https://community.retellai.com/t/no-call-analyzed-webhook-for-some-disconnection-reasons/387) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.