agent changing data before sending in tool
# supporth
Ham
03/13/2025, 7:39 PMany idea why the agent would successfully retrieve a phone number in a call then change a couple digits in the function tool?
trying to send a phone number works most of the time but sometimes it sends the wrong number, and I can confirm it read the correct number from the logs
changes last 4 digits
call id db067eb0-e114-4ae7-aa7e-33130d12da11
https://cdn.discordapp.com/attachments/1349829151741181972/1349829151921541241/image.png?ex=67d485dc&is=67d3345c&hm=2ee6774328f54fc5f7fa4ace23668fd69d4c9314d19fdd56826735b3d9922009&
v
Vapi Support Bot
03/13/2025, 7:40 PMHi there! I've looked into this issue where the agent is changing phone number digits when sending them to function tools.
Based on the documentation, there are a few known issues with phone number handling in Vapi that might explain what you're seeing:
1. **Phone Number Formatting Issues**: There's a known issue where the API might append a US country code (+1) to phone numbers or alter their format during processing. This could potentially affect other digits as well.
2. **Transformation Rules**: Vapi applies specific transformation rules to phone numbers before invoking function tools. According to the documentation, phone numbers undergo manipulation through a process like:
Copy code
javascript
formatted_number: number.number?.replace(/(\+1)(\d{3})(\d{3})(\d{4})/, '$1-$2-$3-$4')h
Ham
03/13/2025, 7:57 PM Copy code
{
"type": "object",
"properties": {
"phone_number": {
"description": "the phone number attached to the clients account"
"type": "string"
}
},
"required": []
}Ham
03/13/2025, 8:02 PMchanged to
Copy code
{
"type": "object",
"properties": {
"phone_number": {
"description": "the phone number attached to the clients account must be a U.S. number in E.164 format",
"type": "string"
}
},
"required": [
"phone_number"
]
}Ham
03/13/2025, 8:02 PMworked first attempt but it seems to be random
Ham
03/14/2025, 1:26 AMworked fine for a bit then started sending number without the +1 formatting
v
Vapi
03/15/2025, 7:32 AMHello Ham,
Please lower the temperature on your LLM to around .6 and this should solve your issue.
h
Ham
03/15/2025, 5:50 PMI will do that thank you, I also told it to just send the 10 digits the contact gives no formating, working so far
v
Vapi
03/16/2025, 6:07 PMGreat to hear Ham! Happy building