inconsistent dynamic variable use in first message
I’m experiencing an issue with dynamic variables when my agent first starts speaking at the beginning of a phone call. When the call connects, the agent sometimes says the variable name itself (e.g., {{agent_name}}) instead of the actual substituted value.
This only happens in the first message and is inconsistent — sometimes it works correctly, sometimes it doesn’t.
As a workaround, I tried splitting the greeting:
First message: “Hello”
Prompt: “My name is {{agent_name}}, how can I help you?”
This fixes the substitution issue but introduces a new inconsistency: sometimes the agent just says “Hello” and waits for a response, other times it continues with the full greeting in one go.
Questions:
Is this a known issue?
Is there a way to guarantee the dynamic variable is always substituted before the first message is spoken?
Will Vapi continue to use the current “first message” structure? I feel the performance here is worse compared to Retell.ai, where the node has a “AI speaks first” option.
Would it be possible to add a “skip user response” option? Sometimes even with an empty edge, the agent still doesn’t continue the conversation automatically.
Thanks in advance for your help,
This only happens in the first message and is inconsistent — sometimes it works correctly, sometimes it doesn’t.
As a workaround, I tried splitting the greeting:
First message: “Hello”
Prompt: “My name is {{agent_name}}, how can I help you?”
This fixes the substitution issue but introduces a new inconsistency: sometimes the agent just says “Hello” and waits for a response, other times it continues with the full greeting in one go.
Questions:
Is this a known issue?
Is there a way to guarantee the dynamic variable is always substituted before the first message is spoken?
Will Vapi continue to use the current “first message” structure? I feel the performance here is worse compared to Retell.ai, where the node has a “AI speaks first” option.
Would it be possible to add a “skip user response” option? Sometimes even with an empty edge, the agent still doesn’t continue the conversation automatically.
Thanks in advance for your help,
