Defining a Tool JSON Schema

Cost and Latency of Multi-Turn Tool Use

Security Risks of Tool Execution

Error Handling and Retries in Agent Loops

Agent Frameworks Overview

Stopping Conditions and Max Iterations

Agent Memory and State Across Steps

Multi-Step Task Decomposition by Agents

Common Tool Types for LLM Agents

Tools vs Functions vs Agents

Agent Reasoning Loops: The ReAct Pattern

What an LLM Agent Is

Structured Output via Function Calling

Handling Invalid or Hallucinated Tool Arguments

Controlling Tool Choice

Parallel and Multiple Tool Calls

The Full Function Calling Loop

Returning Tool Results Back to the Model

Executing the Function in Your Code

Parsing the Model's Tool Call Response

Token Cost of Tools and Loops

The Tool Message Role

Returning Tool Results

Structured Output vs Function Calling

Forcing Tool Choice

Parallel Tool Calls

Multi-Step Function Loop

Parsing Call Arguments

Reading the Tool Call

How the Model Decides to Call

Passing Tool Definitions

Writing Function Descriptions

JSON Schema for Parameters

Defining a Tool Schema

Why LLMs Need Tools

What Function Calling Is

Executing the Function

Stopping Conditions

Handling Hallucinated Calls

Security Risks of Tool Calls

What an LLM Agent Is

Error Handling and Retries

The ReAct Loop

Agents vs Function Calling

Common Agent Tools

Agent Memory and State

Agent Frameworks Overview

How the Model Decides to Call a Tool

Passing Tool Definitions in an API Request

Tool Definitions and JSON Schema

What Function Calling Is and Why It Exists

Sending tool results back

Building the tool-call loop

Parsing tool call arguments

Parameter types and required fields

Passing the tools array

Forcing a specific tool_choice

Detecting a tool call

Executing the local function

Appending the tool result message

Handling parallel tool calls

Preventing infinite loops

Dispatching tool names to handlers

Returning tool errors to the model

Validating arguments against allowed values

Preserving the assistant tool_calls message

Distinguishing final vs tool response

Matching tool_call_id to result

Handling malformed arguments

Writing function descriptions