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IVR / DTMF Tool Issue – Agent Misbehavior
# support
h
@Oshi Raghav @Shaunak ### Problem - The agent is not pressing the required IVR keys. - Instead of invoking the DTMF tool, it incorrectly triggered the transfer call tool. - Sometimes it invokes DTMF tool, but does not press the required key. - Behavior feels inconsistent and “bogus” when bypassing IVR menus. ### Request for Logs Please provide detailed logs explaining: - Why the agent chose 
transfer_call
instead of 
dtmf
. - I have attached the Assistant ID. Could you please check whether the tool is correctly configured? Assistant ID: 7f2232ae-bfb0-4913-823d-654650a9e14e DTMF Tool ID: c5485d6f-b281-42db-84e9-6d999088bdb2 Call IDs: 019db0e7-0ce8-7003-8d88-863a13b2e654 (agent invoked transfer tool instead of DTMF) 019db0d8-fca9-7997-8b2c-33c40c4b36d2 (agent did not invoked DTMF Tool) If you need anything else, please let me know. But kindly resolve this issue, as I am initiating outbound calls to potential leads and encountering this problem.
a
I can help you fix this quickly. From what you described, it looks like a tool-selection issue (agent choosing transfer_call over dtmf) and possibly weak prompting or misconfigured tool priority. I’ve handled similar IVR/DTMF issues before, so this should be straightforward. Send me access or logs and I’ll sort it out @hamza-007
s
Hi, I’ve investigated your calls and the tool configurations. The good news is that both your DTMF Tool and Transfer Tool are configured correctly; the issue is actually related to the model's logic during the call. What Happened in Your Calls Call ...e654 (Transfer instead of DTMF): The voicemail system said, "Now... At the tone, please record your message..." The model (GPT-4o-Mini) misheard the word "Now" and interpreted it as a human answering your prompt. Because your instructions say to transfer when a prospect shows interest, it triggered the transfer_call_tool immediately. Call ...4b36d2 (No tool invoked): The assistant reached the voicemail prompt but failed to recognize it as an IVR menu, resulting in the agent going silent until the call ended. Why This is Happening While our system correctly detected these as voicemails, the detection sometimes arrives a split-second after the LLM has already decided to speak or trigger a tool. Since your prompt doesn't have explicit instructions on how to handle "Press # for more options" vs. a human response, the model is guessing—and in these cases, it guessed wrong.
Recommended Fixes 1. Update your System Prompt (Most Important) You need to give the model a "manual" for voicemails. Add a section like this:
Copy code
markdown
## Handling Voicemail & IVR
If you hear phrases like "At the tone," "Leave a message," or "Press pound for more options," you are on a voicemail system. 
- DO NOT use the transfer_call_tool.
- Use the dtmf_tool to press the keys requested (e.g., if it says "Press # for options", call dtmf_tool with keys="#").
2. Upgrade the Model You are currently using gpt-4o-mini. While fast, it often struggles with the nuance of background IVR messages. Upgrading to GPT-4o will significantly improve the agent's ability to distinguish between a human saying "Now" and a recorded prompt. 3. Tool Description In your dtmf_tool settings, update the description to explicitly say: "Use this tool when you hear an automated system asking to press a key to reach an operator or hear more options."
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