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Generative AI 10 Slides

Tools and Tool Calling in Agentic AI.

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Guide Notes & Explanation

Accompanying breakdown for this slide deck

  • Tools and Tool Calling in Agentic AI

What Are Tools in Agentic AI?

  • Tools are external capabilities that an AI agent can use to perform tasks beyond generating text.
  • Examples include web search, calculators, databases, APIs, code execution, and file systems.
  • Tools allow an AI agent to interact with the outside world instead of only producing responses.
  • An LLM can reason about a task, but tools give it the ability to retrieve information or perform actions.
  • This transforms AI from a question-answering system into a task-performing system.

Why Do AI Agents Need Tools?

  • LLMs have limitations: their knowledge may be outdated and they cannot directly access every external system.
  • They may also struggle with precise calculations, large datasets, and real-time information.
  • Tools solve these limitations by giving agents access to specialized capabilities.
  • A financial agent can query market data, while a coding agent can execute code and inspect the output.
  • The LLM provides the intelligence, while tools provide the capabilities.

What Is Tool Calling?

  • Tool calling is the mechanism that allows an AI model to request the use of a specific tool.
  • The model doesn't directly execute the tool; it generates a structured request describing what the application should do.
  • The application receives the request, executes the tool, and sends the result back to the model.
  • The model then uses the result to continue solving the task.
  • The basic loop is: Think → Call Tool → Observe → Think Again → Act.

How Tool Calling Actually Works

  • Developers first provide the AI model with available tools and their input schemas.
  • The user gives the agent a task that may require one or more tools.
  • The model decides whether a tool is necessary and selects the appropriate one.
  • The application executes the tool using the arguments generated by the model.
  • The tool's output is returned to the model, which uses it to produce the final response or make another tool call.

One Agent Can Use Multiple Tools

  • Real-world tasks rarely require only one capability.
  • An AI agent might use a web search tool to find information, a database tool to retrieve internal data, and a calculator to analyze the results.
  • It can decide which tool to use based on what it needs at each step.
  • Tools can also be called multiple times during a single task.
  • Combining multiple tools allows agents to solve complex, multi-step workflows.

Tool Calling vs Function Calling

  • Function calling is a common mechanism through which AI models interact with external functions.
  • Tool calling is the broader concept of allowing a model to interact with different external capabilities.
  • A function might retrieve customer information, while another tool could search the web or execute code.
  • The terminology differs across AI frameworks and platforms.
  • The underlying idea remains the same: the model decides what capability it needs and provides structured arguments to use it.

What Makes a Good Agent Tool?

  • A good tool should have a clear purpose and a well-defined input/output structure.
  • Tool descriptions should be specific enough for the model to understand when and how to use them.
  • Inputs should be validated because the model can generate incorrect or unexpected arguments.
  • Tools should return useful, structured results instead of unnecessary information.
  • Good tools are designed around real tasks rather than simply exposing every possible API.

Tools Are the Hands of an AI Agent

  • An LLM can reason, plan, and decide, but without tools its ability to interact with the real world is limited.
  • Tools give agents access to data, computation, software systems, and real-world actions.
  • Tool calling provides the connection between the model's reasoning and those external capabilities.
  • As agents become more autonomous, the number and variety of tools they can safely use will continue to grow.
  • The future of Agentic AI isn't just about smarter models; it's about smarter models connected to the right tools.