Harvey's Agent Builder Means Small Law Firms Can Now Build What BigLaw Spent Millions On
Published March 16, 2026 · By The Crossing Report
Published: March 16, 2026 | By: The Crossing Report | 5 min read
Summary
Harvey launched an Agent Builder feature that allows any law firm — not just the enterprise clients that spent millions getting in early — to create custom AI agents for their specific practice workflows. No tech team required. For small and mid-size firms that assumed Harvey was for BigLaw only, this changes the access equation.
What Changed
Harvey made its name at the top of the market. A&O Shearman, Linklaters, and other Magic Circle firms deployed Harvey as part of multi-million-dollar AI initiatives. That's the headline most law firm owners outside BigLaw absorbed — "Harvey is for large firms" — and stopped reading.
Bloomberg's March 2026 reporting on the Agent Builder changes that framing.
Any law firm with a Harvey account can now build custom AI agents for their specific workflows. Not custom in the sense of submitting a feature request and waiting six months — custom in the sense of sitting down, describing what you want the agent to do, and deploying it.
The firm that built a custom NDA review agent by working with Harvey's enterprise team for a year can now be replicated — at meaningful cost — by a 5-attorney firm that understands its own NDA review workflow well enough to describe it.
Why This Matters More Than a Feature Update
There's a pattern in legal technology that keeps repeating: a capability is enterprise-only for 18-24 months, then it reaches a self-service inflection point.
Automated contract review went enterprise-only → Ironclad → now accessible via Spellbook and August with no sales call. E-discovery went enterprise-only → Relativity → now accessible via Clio and simpler tools for smaller matters. Legal research AI went enterprise-only → Westlaw Edge → now accessible via CoCounsel with no seat minimums.
Harvey's Agent Builder is that inflection point for custom legal AI workflows.
The difference between a general AI tool (Claude, GPT-5.4) and a Harvey agent isn't just the legal training data — it's codification. A general AI tool requires you to re-explain your firm's preferred contract language, your standard review criteria, and your practice area context every session. A Harvey agent stores all of that, applies it consistently, and runs the same process on the 50th document as on the first.
That consistency is what BigLaw paid for. It's now available without the enterprise contract.
The Four Agents Worth Building First
1. NDA Review Agent
Define your firm's standard NDA terms — preferred definitions of confidential information, your standard carve-outs, time period positions, and dispute resolution preference. The agent reviews any incoming NDA against those terms, flags deviations, and produces a summary of issues ranked by materiality. A lawyer reviews the flagged items. You're reviewing exceptions, not reading 20 pages to find them.
This is the highest-volume, lowest-judgment task in most transactional practices. It's also the task where AI contract review tools (August, Spellbook) have proven reliable — Harvey's agent layer adds your firm's specific standards on top.
2. Matter Summary Agent
Input a file — documents, correspondence, prior pleadings. The agent produces a structured summary: key parties, dates, obligations, outstanding issues, and risk flags. Output format matches whatever your matter management system expects. For a 3-attorney firm, this replaces the first hour of every new-matter review — the time spent orienting to a file before you can give a client an informed answer.
3. Client Intake Agent
A new client sends their matter information — parties involved, facts, what they want. The agent processes the intake, generates a conflict check summary, identifies the practice area and likely issues, and drafts a preliminary matter overview for attorney review. The lawyer gets to the client conversation having already read a structured briefing, not raw emails.
4. Document Comparison Agent
You have two versions of a contract. The agent identifies every change, categorizes changes by type (substantive vs. formatting, risk-relevant vs. administrative), and produces a negotiation summary — what changed, what the other side pushed for, what positions were traded. The lawyer reviews the summary and addresses the substantive items. Not redline review page by page.
What to Do This Week
The Agent Builder is accessible to firms with a Harvey account. If you don't have one, the access barrier has changed — Harvey's enterprise-only positioning has shifted toward a broader market.
The practical steps:
Identify your highest-volume, lowest-judgment review task. In most transactional practices, that's NDA review. In most litigation practices, it's document triage (identifying which documents in a production are actually relevant).
Write down your review criteria in plain language. What are the issues you look for in every NDA? What flags trigger escalation to a partner? What positions does your firm never concede? That document is the brief you give the Agent Builder.
Test the agent on ten historical matters before using it on live client work. Compare the agent's output to the reviews your attorneys did manually. The gaps are the places to refine your criteria.
The firms that build these workflows now will have 6-12 months of operational experience by the time the next generation of small-firm legal AI tools reaches the market. That lead compounds.
Related Reading
- AI Tools by Practice Area: Tax, Contracts, and Consulting — Purpose-built legal AI tools for contract review, M&A due diligence, and litigation support
Source: Bloomberg coverage of Harvey's Agent Builder, March 2026. For related coverage, see Harvey + Microsoft 365: What the M365 Copilot Integration Means for Small Law Firms and BigLaw Just Deployed AI Agents — Here's What's Coming for Small Firms.
Frequently Asked Questions
What is Harvey's Agent Builder?
Harvey's Agent Builder is a feature that allows any law firm — including small and mid-size practices — to create custom AI agents tailored to their specific workflows and practice areas, without requiring a technical team. Previously, building custom legal AI workflows required either a Harvey enterprise contract (with multi-seat minimums) or custom development work. The Agent Builder changes that access equation: any firm with a Harvey account can now define their own agents using plain-language instructions.
Do small law firms need a technical team to use Harvey's Agent Builder?
No. That's the distinguishing feature of the Agent Builder — it's designed for lawyers, not engineers. You describe what you want the agent to do in plain language, specify the inputs (contract types, documents, practice area context), define the outputs, and Harvey builds the agent. No coding required. The skill required is clarity about your workflow, not technical knowledge.
What can a small law firm build with Harvey's Agent Builder?
The most common starting points for small and mid-size practices are: NDA review agents (flag deviations from your standard terms), matter summary agents (ingest a file and produce a structured summary of key parties, dates, and obligations), client intake agents (process new matter information and generate a conflict check summary), and document comparison agents (compare two drafts and summarize changes). These are the same agent types that BigLaw firms built at significant expense — now accessible without the enterprise budget.
How is Harvey's Agent Builder different from using a general AI tool like Claude or ChatGPT?
The key difference is that Harvey's Agent Builder produces repeatable, codified workflows — not one-off prompts. A general AI tool requires you to re-explain the context and instructions every session. A Harvey agent stores your firm's specific rules, preferred language, and review criteria, and applies them consistently every time, across any number of documents. It's the difference between an ad hoc conversation and a standardized workflow.
What did BigLaw spend to build custom Harvey agents?
Firms like A&O Shearman, Linklaters, and others in Harvey's early enterprise cohort deployed custom Harvey agents as part of significant technology investments — in some cases described as multi-million-dollar AI programs. The Agent Builder compresses that investment to the cost of a Harvey subscription plus the time it takes a lawyer to define the workflow. The underlying legal AI capability is the same.