Memory Variables {{placeholders}} Not Being Replaced in System Prompt
Hi VAPI Team,
I have an issue where {{variable}} placeholders in my system prompt are not being replaced during phone calls.
Configuration:
I have an issue where {{variable}} placeholders in my system prompt are not being replaced during phone calls.
Configuration:
- Assistant ID: 72577c85-81d4-47b4-99b5-0ca8b6ed7a63
- Model: gpt-4o-mini (OpenAI)
- System prompt contains: {{user_name}}, {{conversation_count}}, {{last_topics}}, {{conversation_summary}}
- Webhook URL: https://ocixoxjozzldqldadrip.supabase.co/functions/v1/vapi-webhook
- firstMessageMode: assistant-speaks-first-with-model-generated-messageWebhook Works Correctly:I tested my webhook directly - it correctly returns:{"assistantId": "72577c85-81d4-47b4-99b5-0ca8b6ed7a63","assistantOverrides": { "variableValues": { "user_name": "Robert", "conversation_count": "5", "last_topics": "Palenie, Stres, Praca", "conversation_summary": "User discussed quitting smoking..." }}}Problem:When I check recent call logs (e.g. call ID 019a26b4-974e-7bbb-81c0-4f248d1f9a34), the system message shows:
- {{user_name}} - NOT replaced (literal text sent to GPT)
- {{conversation_count}} - NOT replaced
- No webhook logs in call artifact
- AI responds as if variables are still placeholdersQuestions:
- Does assistant-request webhook get called for inbound phone calls?
- Are {{variables}} supposed to work with OpenAI models or only Claude?
- Is there a configuration I'm missing to enable variable replacement?
- How can I debug this - are there webhook logs I can check?Expected: AI says "Cześć Robert! To nasza 5. rozmowa..." (Hello Robert! This is our 5th conversation)Actual: AI says generic greeting, doesn't use memoryPlease help! Thank you!
