Getting Started with AgentFlow

Welcome! This section takes you from zero to a working AI agent — step by step, with real code at every stage.

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Your Path

Step	Page	What You'll Do	Time
1	What is AgentFlow?	Understand what you're building and why	3 min
2	Installation	Install AgentFlow + your LLM provider	5 min
3	Hello World	Build a working agent with tool calling	10 min
4	Core Concepts	Learn the 5 building blocks you use every time	5 min

Total: ~23 minutes to your first working agent.

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Choose Your Starting Point

I'm brand new to AI agents → Start with What is AgentFlow? to get oriented, then follow the path above.

I know what agents are — just let me build → Jump to Installation → Hello World

I prefer understanding theory first → Core Concepts → Hello World

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What You'll Build

By the end of this section you'll have a tool-calling AI agent that:

• Accepts user messages
• Decides when to call Python functions (tools)
• Returns a synthesized response from the LLM

Here's the complete code you'll understand by the end:

from dotenv import load_dotenv
from agentflow.graph import Agent, StateGraph, ToolNode
from agentflow.state import Message
from agentflow.utils.constants import END

load_dotenv()

def get_weather(location: str) -> str:
    """Get the current weather for a location."""
    return f"The weather in {location} is sunny, 72°F"

tool_node = ToolNode([get_weather])

graph = StateGraph()
graph.add_node("MAIN", Agent(
    model="google/gemini-2.5-flash",
    system_prompt="You are a helpful assistant.",
    tool_node_name="TOOL",
))
graph.add_node("TOOL", tool_node)
graph.set_entry_point("MAIN")

app = graph.compile()

result = app.invoke({
    "messages": [Message.text_message("What's the weather in New York?")]
})
print(result["messages"][-1].content)

15 lines. One agent. Tool calling included.

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What's Next After Getting Started?

Once you've completed this section, you'll be ready for:

• Tutorials — Step-by-step guides for real-world patterns (memory, RAG, multi-agent, streaming)
• How-To Guides — Quick recipes for specific tasks
• Reference — Full API documentation for every class and method

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Let's go! Start with What is AgentFlow? →