AI Support & Agents

Tool Use

Definition

Tool use is the ability of an AI model to invoke external functions, APIs, or systems — like looking up an order or issuing a refund — instead of only generating text, so it can act on real data rather than just describe it.

Also known as: tool callingfunction callingagent tools

How it works

The model is given a set of tools, each described with a name, purpose, and expected inputs. When a request requires live data or an action, the model outputs a structured call — the tool name plus arguments — which the surrounding system executes. The result is fed back to the model, which uses it to continue reasoning or write its final answer.

In customer support this is what lets an AI agent read a customer's account from a backend, apply a policy, and take an action such as updating a record — all inside a single conversation.

Why it matters for support

Tool use is the mechanism that turns a text-only assistant into something that can resolve tickets. Without it, an AI can only explain how to do something; with it, the AI can actually do the thing on the customer's behalf.

Grounds answers in live data instead of static text
Enables actions like refunds, updates, and lookups
Is the technical foundation of agentic AI

Frequently asked

Is tool use the same as function calling?

Largely yes. "Function calling" is the model producing a structured request to run a named function; "tool use" is the broader term for the model invoking any external capability. The terms are often used interchangeably.

How does tool use differ from RAG?

RAG retrieves reference text to ground an answer; tool use lets the model call a function that can read live data or perform an action. Many agents combine both.

How Macha connects custom tools

Related terms

Function Calling

Function calling is a capability that lets a language model request that a predefined function or API be run — returning the function name and structured arguments — so the model can fetch live data or take actions instead of only generating text..

Agentic AI

Agentic AI is AI that doesn't just answer questions but takes actions — it plans multi-step tasks, calls tools and APIs, and works toward a goal end to end with little or no human intervention..

Custom Tools

In Macha, a custom tool lets an AI agent call any HTTP API endpoint you configure — so an agent can read live data or take an action in a system Macha doesn't have a built-in connector for, without waiting for a marketplace app..

AI Agent

An AI agent is a software system that uses a language model to understand a request, decide what to do, and take actions — calling tools, retrieving data, and completing tasks — rather than just returning a single scripted answer..

Retrieval-Augmented Generation (RAG)

Retrieval-augmented generation (RAG) is a technique where an AI model retrieves relevant information from your own knowledge sources at query time and uses it to ground its answer, instead of relying only on what it memorized during training..

Put these ideas to work

Macha is an AI agent layer that sits on top of the help desk you already run — Zendesk, Freshdesk, Front, Intercom, or Gorgias.

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