Legal & Compliance

How to review contracts with AI

The short answer

AI contract review works best as a first-pass assistant for lawyers and trained contract managers. The model checks each clause against your written playbook, quotes the language it relies on, flags missing or off-standard terms, and suggests fallback language from your approved clause library. A qualified person reviews every issue and decides; the tool does not give legal advice.

What this automation does

The tool does the reading a lawyer would otherwise do line by line, then hands over an issues list the lawyer can work through quickly.

  1. Submit. A lawyer or contract manager uploads the agreement, or opens it in Word with an add-in, and picks the agreement type and which side you are on.
  2. Normalize. The document is converted to clean text with clause numbers, defined terms and cross-references preserved. Existing tracked changes from the counterparty are extracted separately.
  3. Resolve definitions. Defined terms are collected first, so a clause using “Losses” or “Confidential Information” is read with its actual definition.
  4. Check against the playbook. For each playbook topic, such as limitation of liability, indemnity, IP ownership, confidentiality, termination, auto-renewal, assignment, governing law and data protection, the model finds the relevant clause, quotes it and compares it with your standard and fallback positions.
  5. Flag missing terms. The model reports playbook topics with no matching clause, such as a vendor agreement with no data security obligations.
  6. Suggest language. For deviations, it proposes replacement text drawn from your approved clause library, not freshly invented wording.
  7. Lawyer decides. The issues appear as Word comments or a review memo with risk levels. The lawyer accepts, edits or rejects each one, and their choices are logged to improve the playbook.

When it is worth building

The volume test: if your legal team reviews dozens of similar commercial agreements a month and most of the time goes to spotting the same handful of issues, a playbook-driven first pass saves real hours. It is especially useful for vendor paper, where every counterparty’s template is different and the issues are in different places.

It is not worth building for low-volume, high-stakes work such as M&A documents or bespoke financing agreements, where every clause is negotiated from scratch. It is also not the first step if you lack a playbook; writing one with your lawyers is often the most valuable part of the project, with or without AI. And if an off-the-shelf review product fits your agreement types and data rules, compare it honestly with a build. Our custom agent vs off-the-shelf comparison lays out that decision.

Architecture

LayerWhat we useWhy
Document intakeWord add-in, or upload from SharePoint, Box or Google DriveLawyers stay in Word, and documents stay in the repository your firm or company already secures
ParsingA DOCX parser that keeps numbering, definitions and tracked changesClause structure matters; flattening a contract to plain text loses meaning
PlaybookStructured records per topic: standard, fallbacks, escalation triggersLegal edits rules directly, and every flag cites the rule it applied
Clause libraryApproved language stored with tags and version historySuggested edits come from text your lawyers already approved
ModelClaude through the API, with long context for full agreementsReads a complete MSA with its exhibits and follows a strict output schema
Quote verificationCode that checks every quoted passage against the sourceRemoves issues based on text that is not in the contract
Matter linkClio or your matter system through its APIReview results attach to the right matter with the right permissions
NotificationsMicrosoft Teams or emailTells the requester when the first pass is ready for legal

How to build it

  1. Write or formalize the playbook. Start with the two or three agreement types that make up most of your volume. For each topic, write the standard position, acceptable fallbacks and walk-away points, in your lawyers’ words.
  2. Build the clause library. Collect approved fallback language from past negotiations, with the context in which each was accepted.
  3. Assemble a test set. Gather 30 to 50 past agreements with the issues your lawyers actually raised. This is how you will measure the tool.
  4. Build parsing and definitions. Get numbering, defined terms and cross-references right before any prompt work. Most quality problems trace back to bad parsing.
  5. Run the playbook check topic by topic. One focused pass per topic is more reliable than one giant prompt for the whole agreement.
  6. Verify quotes and score against the test set. Measure what the tool flagged that lawyers also flagged, what it missed, and what it flagged wrongly.
  7. Deliver in the lawyer’s workflow. Output as Word comments or a memo attached to the matter. Pilot with one or two lawyers for a month before wider use.

What breaks in production

  • Order of precedence. An MSA says one thing and the order form overrides it. The tool must read the full contract stack and the precedence clause, or it will approve terms that a later document changes.
  • Hidden counterparty edits. Incoming drafts sometimes contain tracked changes or unflagged edits to your own paper. Compare against your template version, not just the playbook.
  • Absence errors. A model reports a clause as missing when it sits in an exhibit, or misses that it is missing. Lawyers should confirm every “missing” flag.
  • Long scanned agreements. Image-only PDFs need OCR first, and quote verification gets weaker. Mark these as lower confidence.
  • Playbook drift. Lawyers start accepting a fallback that is not in the playbook. Review logged decisions monthly and update the rules.
  • Over-trust by business users. A sales lead reads “no issues found” as approval. The output must always say who still needs to approve.

Timeline and cost

Expect four to eight weeks, with playbook work and test-set evaluation taking a large share. Lumeor builds this in the range of $18,000 to $45,000, depending on the number of agreement types, whether output goes into Word or a matter system, and how much clause library work is needed. Model usage per agreement is usually small next to the cost of an hour of legal time, but long agreements with many passes add up, so we estimate it on your test set.

How to measure success

  • Lawyer minutes per first-pass review, by agreement type
  • Precision: share of flagged issues the lawyer agrees are real
  • Recall: share of issues the lawyer found that the tool also found, measured on a sampled set each month
  • Share of suggested edits accepted with little or no change
  • Turnaround time from request to first response for the business
  • Playbook updates made from logged decisions each quarter

Contract review sits in the middle of a larger flow. Contract intake and routing gets agreements to legal with the right context, and NDA generation takes the simplest agreements off legal’s desk entirely.

Frequently asked questions

Can AI replace a lawyer for contract review?

No. AI can speed up the first pass by finding clauses, comparing them with your playbook and drafting suggested edits, but deciding what risk is acceptable and what to negotiate is legal judgment. The tool's output is a review aid for a lawyer or a contract manager working under legal's guidance, not legal advice.

Is it safe to send contracts to an AI model?

Use API access, never consumer chat apps, for client or counterparty documents. OpenAI and Anthropic do not train on API data by default, and zero-data-retention terms may be available for eligible customers. Lawyers also have professional duties around confidentiality and competence when using generative AI; the ABA addressed these in Formal Opinion 512 in 2024, and state bars have issued their own guidance.

What is a contract playbook and do we need one?

A playbook lists, clause by clause, your standard position, the fallbacks you will accept and the points where legal must be involved. You need one. Without it, a model can only tell you what a clause says, not whether it is acceptable to you, and its sense of acceptable will be generic.

How do you stop the AI from making things up about a contract?

Every issue must quote the exact contract text it relies on, and code checks that the quote appears verbatim in the document. Issues with failed quotes are dropped. The tool also has to say when a clause is missing, such as no limitation of liability, which a person then confirms.

Should we buy a contract review product instead?

Often, yes. Several products work inside Microsoft Word and handle common agreement types well. Building makes sense when your playbook is specialized, when you need the review tied to your own matter system and clause library, or when your data rules rule out a vendor's hosting.

Can non-lawyers use it to approve contracts?

Only within limits legal sets. A common pattern lets a contract manager handle NDAs and low-value agreements on your own paper when the tool finds no deviations, and sends anything else to a lawyer. The tool never marks a contract as approved; a person does.

Next steps