AutoGPT/docs/platform/agent-builder-guide.md

Agent Builder Guide

Overview

The Agent Builder is the visual editor where you design and build agents by connecting blocks together on a canvas. Each block is a single action — like generating text, calling an API, or processing data — and you wire them together to create automated workflows.

URL: platform.agpt.co/build

The Builder Interface

When you open the builder, you'll see:

• Canvas: The main workspace where you place and connect blocks
• Blocks Menu: A panel on the left-hand side where you browse and search for blocks
• Save Button: Save your agent with a title and description

Working with Blocks

Types of Blocks

Blocks fall into three categories:

Type	Description
Input Blocks	Define what information the agent needs when it runs. These become the input fields users fill in when starting a task. Types include text inputs, file inputs, and more.
Action Blocks	Perform operations — AI text generation, image creation, API calls, data processing, and hundreds of integrations with external platforms.
Output Blocks	Define what the agent returns as its result. These become the visible output when a task completes.

Input and output blocks define the schema of your agent — they determine what users see when running the agent. All other blocks inside the agent are internal and not exposed to the user at runtime.

{% hint style="info" %} There is also a special type of input block: Trigger Blocks. These allow your agent to be activated by external events via webhooks rather than manual input. See Scheduling & Triggers for details. {% endhint %}

Adding Blocks

1. Open the Blocks menu on the left-hand side of the builder
2. Browse categories or use the search bar to find a specific block
3. Click on a block to add it to the canvas

There are hundreds of blocks available, integrating with many platforms and services.

Connecting Blocks

Blocks have input pins and output pins. Pins are typed — they handle specific data types like text, numbers, files, and more.

To connect blocks:

1. Click on an output pin of one block
2. Drag to an input pin of another block (or simply click the output pin, then click the input pin)
3. A connection line will appear between the two pins

When the agent runs, data flows along these connections. This is visually represented by a coloured bead that slides along the connection line from the output pin to the input pin.

Configuring Blocks

Many blocks have settings you can configure directly on the block. For example:

• The AI Text Generator block lets you choose which language model to use
• Integration blocks may require credentials (see Integrations & Credentials)
• Some blocks allow you to hardcode values on their input pins instead of connecting them to other blocks

If a block requires a credential you haven't connected yet, a credential bar will appear prompting you to add it (via OAuth, API key, or username/password depending on the service).

Saving Your Agent

To save your agent:

• Press Ctrl+S, or
• Click the Save button in the builder

When saving, you can provide a title and description for the agent. This is a local save to your personal library. For publishing to the public marketplace, see Publishing to the Marketplace.

{% hint style="info" %} There is currently no draft vs. saved state — saving an agent immediately updates it in your library. {% endhint %}

Navigating Back to Your Library

After saving, click the Agents button in the navigation bar to return to your library and find your agent.

Editing an Existing Agent

To open an existing agent in the builder:

1. Go to your Agent Library (click Agents in the nav bar)
2. Click on the agent you want to edit
3. Click the three dots menu (⋯) on the far right-hand side of the screen
4. Select Edit Agent

This will open the agent in the builder with all its existing blocks and connections.

Error Handling

When a block fails during execution, it produces data on its error pin. As the agent creator, you decide how to handle errors:

• Surface the error: Connect the error pin to an output block so the error is returned as the agent's result
• Handle gracefully: Connect the error pin to other blocks that provide fallback behaviour, ensuring the agent continues working even when individual blocks encounter problems

Tips

• Name your input and output blocks clearly — these names become the labels users see when running your agent
• Test incrementally — save and run your agent frequently as you build to catch issues early
• Use the search in the blocks menu to quickly find what you need among hundreds of available blocks
• Check the pin types — connections only work between compatible pin types