Introduction

Overview & Philosophy Installation & Setup Quickstart Core Concepts

Agents & Execution

Creating & Configuring Agents Execution & Stepping Structured Outputs (agent.json)State & Lifecycle Management Agent Forking

Tools & Function Calling

Defining Tools Schema & Validation Dynamic Tools & Custom Resolution Runtime Tool Management

Events

Event System Overview

onBeforeStep onAfterStep

onBeforeModelInvocation onModelInvocation onAiMessage onAfterModelInvocation

onBeforeToolCall onToolCall onAfterToolCall

Agent Context

Understanding AgentContext Dynamic & Scoped Instructions Message History Manipulation Runtime Agent Mutation

State & Stores

Store Primitives Local Stores Global Stores Scoped Stores Message Metadata & Typing

Hooks & Extensibility

Hook System Overview Creating Custom Hooks Managing Hooks on Agents Hook Scoping & Lifecycle

Built-in Hook Presets

MCP Client Preset Orchestration Preset Guardrail Preset Human-In-The-Loop Preset

Error Handling & Troubleshooting

Error Hierarchy & Exceptions Tool Call Failures & Recovery Debugging & Tracing

TypeScript & Generics Guide

Generic Parameters Reference Tool Parameter & Return Types Typing Hooks & Contexts

API Reference

Fragola Class Agent Class AgentContext Class Events & Payloads Store & Utility Functions

Error Hierarchy & Exceptions

Error Hierarchy & Exceptions

Coming soon.

Tool Call Failures & Recovery

Tool Call Failures & Recovery

Coming soon.

Debugging & Tracing

Debugging & Tracing

Coming soon.

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Error Hierarchy & Exceptions Tool Call Failures & Recovery Debugging & Tracing