Voice AI
What is Function calling?
Function calling is a language model's ability to trigger a predefined external action, such as checking a calendar or updating a record, by producing a structured request that software then executes.
Also called: tool calling, tool use
A developer defines each function with a name and parameters. During the conversation the model decides when to use one, fills in the parameters from what the caller said, receives the result and carries on. If a caller asks for Saturday, the agent checks availability, learns that 11 am and 4 pm are free, and offers both. Each call to an external system adds a little delay, so voice agents often cover the gap with a short phrase.
Function calling is what turns talking into doing. Outpero exposes it as opt-in actions for each AI employee: booking a real calendar slot, reading or writing a spreadsheet live, calling a custom API, and sending a WhatsApp message during or right after the call, so the outcome is acted on before the caller hangs up.
What is Function calling?
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Function calling is a language model's ability to trigger a predefined external action, such as checking a calendar or updating a record, by producing a structured request that software then executes. A developer defines each function with a name and parameters. During the conversation the model decides when to use one, fills in the parameters from what the caller said, receives the result and carries on. If a caller asks for Saturday, the agent checks availability, learns that 11 am and 4 pm are free, and offers both. Each call to an external system adds a little delay, so voice agents often cover the gap with a short phrase.
Why does Function calling matter?
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Function calling is what turns talking into doing. Outpero exposes it as opt-in actions for each AI employee: booking a real calendar slot, reading or writing a spreadsheet live, calling a custom API, and sending a WhatsApp message during or right after the call, so the outcome is acted on before the caller hangs up.
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