Custom API

What is the Custom API tool?

The Custom API tool is a built-in capability in the Agno framework that allows AI agents to call any custom http api endpoint. When added to an agent in Agno Builder, the agent can autonomously decide when to invoke this tool based on the user's request.

This is a free tool — no API key or external account is needed. It works out of the box when you add it to any agent.

How to use Custom API in Agno Builder

1. 1

   Create an agent

   Drag an Agent node onto the canvas in Agno Builder, or use one of the built-in templates.

2. 2

   Enable Custom API

   Click the agent, go to the Tools tab, and toggle on "Custom API" from the core category.

3. 3

   Test in chat

   Open the chat panel and send a message. The agent will automatically use Custom API when relevant.

4. 4

   Export Python code

   Click File > Export Python to get clean, runnable code with the correct imports for Custom API.

Python code example

This is the code Agno Builder exports when you use Custom API:

from agno.agent import Agent
from agno.models.openai import OpenAIChat
from agno.tools.api import CustomApiTools

agent = Agent(
    name="Custom API Agent",
    model=OpenAIChat(id="gpt-4o"),
    tools=[CustomApiTools()],
    instructions=["Use the custom api tool to help the user."],
    markdown=True,
)

agent.print_response("Help me with a custom-api task")

Install with: pip install agno