Early Access Feature

New Agent Builder

The new Agent Builder will make it easier to create and customize powerful agents using simple text instructions, conversational building, and reusable templates.

Overview

The new Agent Builder is Harvey's text-based experience for creating custom workflow agents. Instead of mapping out every prompt and block step, you describe what you want the agent to produce — and Harvey helps you refine, test, and improve those instructions through conversation.

This is a fundamental shift from the existing builder: rather than building each step to execute, you can now define the outcome and let the agent build the process for you.

With the new Agent Builder, you can:

Choose various ways to build
- Create and edit agents using simple conversation with Harvey
- Start from existing templates or Library agents instead of building from scratch
- Upload Markdown files to generate agents instantly
Visualize how your agent runs with a flow diagram
Access 500+ new legal agents in your Library. Available for all users by default; Admins can manage access.
Continue to embed knowledge sources or vaults into your agents

Before You Start

Confirm that you have:

Agent Builder permissions to create Workflow Agents
Early Access to Long Horizon Agents. The Agent Builder experience performs best when the user has access to the full bundle of agent capabilities.

Agent Builder Version Comparison

This chart covers the main differences between our Agent Builder versions.

	Workflow Builder - Current Version	New Agent Builder- Early Access
How you build	Assemble block steps manually Specify each step that must be taken	Write outcome-focused instructions Harvey asks for your input and creates the steps to execute
How you iterate and refine	Rebuild blocks	Chat with Harvey
How you add sources	Added per block	Added once, you describe how they should be used
Output types	No change	No change

The Relationship Between Long Horizon Agents & Workflow Agents

If you're exploring Agent Builder and Long Horizon Agents (LHA) in Early Access, here's a simple way to think about how they work together.

Long Horizon Agents (LHA) is Harvey's mode for tackling complex, multi-step tasks in Assistant. You don't turn it on manually, Harvey activates it automatically when your prompt calls for it. A good sign it's running: Harvey will ask you follow-up questions before getting started.

Workflow Agents are what you build when you want to run that same process again. If LHA produces a strong result, Agent Builder lets you save and refine those instructions so anyone on your team can replicate it consistently without starting from scratch.

	Long Horizon Agents (LHA) - Early Access	Workflow Agents with New Agent Builder - Early Access
Where they’re used	Assistant will automatically start a LHA when appropriate based on your prompt	Workflow Agents are manually started when selected in Assistant or from the Library
Best for	Producing work product (files, review tables) when the task is complex and does not have a defined process	Producing work product when the task is complex and follows a standard procedure or repeatable process
How you build	LHA are made through conversation with Harvey, but aren't saved for reuse	Through conversation with Harvey, focused on desired outcome
Output types	PPT, spreadsheet, file	PPT, spreadsheet, file
Iteration	Chatting with Harvey	Chatting with Harvey
How you add sources	Ad hoc, depends on each user Example: Agent asks user for files, user uploads their own files	Pre-built with agent Example: An agent builder adds files or sources to the agent. Every time a user runs the agent, these same sources are used. Additional sources can be added by users in follow up conversation.

Tip: Use Assistant LHA when you need a one-time work product. Build an agent when you want to make that work repeatable and scalable.

Use Cases

The new Agent Builder is designed for repeatable, multi-step workflows that benefit from consistency and automation. Sample use cases:

For Admins: Manage New Agents in Library

As an Admin, if you’d like to adjust access to the 500+ new agents added, you can modify what’s available in your workspace library by following the steps below.

Open the Build tab to open the Workflow Agents dashboard
Select the tab Created by Harvey to filter the available workflow agents
Filter by practice area, or sort columns to narrow your search
Use the check boxes to select workflow agents
Choose an update:
1. Unpublish to hide them from the Library
2. Publish to share them to the Library
3. Delete ones you never want used

Editing Agents from Library

You can edit a pre-built agent to customize it further.

Select the agent you want to use as the starting point.
Choose Edit agent

Image of a workflow agent selected and the edit agent option

You will be directed to Agent Builder, where you can directly edit, test, and save the agent instructions.

How to Create an Agent with the New Agent Builder

Step 1: Open Agent Builder

Select the Build tab from Harvey’s main side panel menu
Select Agent Builder
Choose Create workflow agent
Choose how you want to build:
1. Agent Builder — this is our new version; use words to build
2. Workflow Builder — the version you’re familiar with; use blocks to build
Choose how you want to start:
1. Chat with Harvey — describe what you want Harvey to do
2. Import a Markdown (.md) file — Import a Claude skill or other existing instructions
3. Build from scratch — write out instructions, or copy in prompts

Step 2: Build with Instructions

Image of an interface in Harvey that prompts the user to enter a description of what the agent should do.

Enter a description of what the agent should do. Be outcome-focused, describe what the agent should produce, not every step it should take.
1. Example prompt: "Analyze contracts for specific clauses and summarize risks in a structured table."
Harvey will ask follow-up questions to refine your instructions. Answer them to sharpen the agent's behavior.

The agent editor will open on the right-side, while you can continue to ask Harvey to iterate on the left. You can also edit the instructions directly in the editor at any time.

Tip: Starting with "Can you build me an agent that..." is a reliable way to trigger a build proposal from Harvey.

Step 3: Add Context

In the editor, you can add or adjust files and sources to give the agent context, such as knowledge sources, vaults, or templates. Direct file uploads are coming soon.

Select Manage by sources or files to make your selections
Once your context is added, use the text box to tell Harvey how and when to use each source.

Note: If you want Harvey to use specific sources, especially at a particular step, make sure those sources are added and explicitly instruct the agent when to use each source.

Step 4: Review Agent Logic

Switch between views using the tabs at the top of the editor:
1. Instructions view — Default view, edit agent behavior directly
2. Diagram view — Visualize how the agent may execute (read-only)

Both can help give you an understanding of the steps the agents has planned.

Note: The diagram view is intended as a visual aid and does not represent exact steps the agent will take every time.

Step 5: Test and Iterate

If you have immediate changes to make, simply ask Harvey to make those changes using the chat conversation.
Use the view changes option to review edits in redline or side-by-side style.
When you’re ready, use the Test option to evaluate how the agent performs.
Review the output and tell Harvey what it missed, so that it can refine your instructions based on the results.
Repeat until the output meets your standards.

Tip: Use test runs to iterate rather than trying to perfect instructions upfront. Faster iteration leads to better agents.

Save, publish, and share capabilities remain the same as our legacy builder.

Refer to Permissions and Sharing in Agent Builder for details.

Notes and Limitations

No local file uploads during agent creation — To add files to your agent, they must be in a vault. Users can still upload ad hoc local files when using the agent, but if you want specific files to be used on every agent run, make sure they’re in a vault.
Workflow builder remains available — Existing workflows are not affected, though future development is focused on the new Agent Builder.

FAQs

Access

Q: Who can use the new Agent Builder?

The new Agent Builder is available to users with Agent Builder permissions. Ask your workspace admin about access.

Performance

Q: How is the new Agent Builder different from the current Workflow Builder?
The new Agent Builder will replace rigid, block-based construction with a more flexible text-based approach. You will be able to define and refine agent behavior through direct instruction editing, making the creation process faster and more intuitive.

Q: How will this improve the experience of running agents?

The new Agent Builder will enable agents to collect required inputs more intelligently—either upfront or while processing. This will reduce the need for step-by-step prompting and create a more seamless experience compared to previously built custom Workflow Agents.

Building

Q: Do I need to start from scratch when creating an agent?
No. You can edit agents from the Harvey Library and use them as a starting point, making it easy to build on proven templates and adapt them to specific workflows. The ability to convert block-based workflows into the new agent format will be coming in a future update.

Q: Do I need to define every step of the workflow?

No. You define the desired outcome and key instructions. The agent determines how to execute the steps.

Q: Can agents automatically use my data sources?

No. You must explicitly instruct the agent which files and sources to use and when.

Q: What happens to my existing Workflows Agents?

Nothing. Existing workflows are not affected. Workflow Builder remains available, but future development is focused on the new Agent Builder.

Q: Can I specify which AI model the agent uses?

Not currently. Harvey automatically selects the best model for the task.

Q: Can I ask Harvey to build a custom agent with me in Workflow Builder?

Yes — You can use Build with Harvey in Workflow Builder.

Other

Q: How is this different than Words to Workflows?

Words to Workflows helps you set go from idea to block-based setup in one step. However, it lacked the conversational iteration now available. The new Agent Builder is a completely redesigned experience for how custom agents are created and stored as text-based instructions.

Q: How is the new Agent Builder different from Harvey Assistant?

Harvey Assistant (LHA) is for one-time work products — you run it, get an output, and you're done. The new Agent Builder is for making that work repeatable. A workflow agent bundles not just instructions but also knowledge sources, vaults, and templates, so every run starts from the same high-quality baseline.