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Reverse-engineering Anthropic’s AI governance legal skills

What Anthropic’s open legal skills teach us about building AI workflows — and why this does not make Harvey or Legora obsolete.

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Subject
Anthropic’s Claude for Legal project, and its ai-governance-legal plugin
Licence of the source
Apache License 2.0
Written for
Anyone building or evaluating an AI skill — no coding background assumed
Reading time
About 25 minutes

An independent case study. This is an educational case study of an open-source project. It is not affiliated with, sponsored by, or endorsed by Anthropic, Harvey, or Legora. It simplifies and adapts concepts for teaching: the code samples below are teaching illustrations, not verbatim reproductions of Anthropic’s files. Read the repository itself for the real thing.

The objective is not to reproduce Anthropic’s work line by line. Instead, we are going to take it apart like engineers examining a machine:

What is a skill? What does the .md file actually do? Why was the workflow divided this way? What belongs in the skill and what belongs elsewhere? And how is this different from buying a legal AI platform such as Harvey or Legora?

Or listen · audio explainer

A spoken walkthrough of the same ground, if you would rather hear it than read it. The written version below is the fuller one — it carries the diagrams, the file listings, and the checklist.

21 min 55 sec Open in Google Drive (opens in a new tab)

Part one

Skill or platform?

The question every lawyer asks first, and why the answer is not a winner-takes-all one.

Section one

Start with the question everyone asks

When lawyers see something like Anthropic’s Claude for Legal project, an understandable reaction is:

“If Claude can do legal work and Anthropic is giving away legal skills, why aren’t Harvey, Legora, and similar legal AI companies suddenly out of business?”

The short answer: because a skill is not the same thing as a complete legal AI platform. And even Claude itself is not merely a model any more. The boundaries are converging. That is what makes this interesting.

Anthropic describes legal AI as an ecosystem that can include connectors to firm data, reusable skills, subagents, plugins, APIs, and enterprise controls. In Anthropic’s own explanation, connectors provide access to data, skills teach Claude how to perform repeatable legal tasks, and plugins bundle capabilities for particular practice areas.

Harvey and Legora are approaching much of the same problem from another direction: they provide legal-specific environments that package many of these capabilities into a finished product. Harvey currently combines purpose-built agents, legal research, document storage and bulk analysis through Vault, collaboration, institutional knowledge, workflow orchestration, integrations, analytics, and enterprise controls. Legora similarly combines agentic execution with workflows, drafting, review, legal research, database search, firm knowledge, permissions, and legal-specific tools.

So this is not Claude Legal versus Harvey and Legora, winner takes all. A better picture is a stack, and companies can participate at several layers at once — which, increasingly, they do.

Legal work experience matters · collaboration · Word · review
Legal applications research · vaults · diligence · contracts
Workflows, agents, and skills “how should this legal task be done?”
Firm knowledge and external data precedents · matters · research sources
Connectors, permissions, governance who may reach what, and on whose authority
Foundation models Claude · GPT · other models

Section two

So why aren’t Harvey and Legora “out of business”?

Because having an intelligent model plus a workflow definition is not the entire product problem.

Consider what Harvey currently provides. Its platform includes agents, research, Vault, knowledge resources, Shared Spaces, workflows, contract intelligence, integrations, administrative capabilities, and enterprise security features. Harvey’s Vault can organise and analyse large document collections and connect with document-management systems while maintaining permissions and governance controls. Legora’s Workflows similarly lets lawyers orchestrate legal tasks using drafting, tabular review, legal research, database search, institutional standards, reference materials, and access controls.

That productisation matters. Imagine that a law firm wants an AI system for due diligence. The AI reasoning might be only one portion of the problem. You also need to answer:

A SKILL.md file does not magically solve all of those problems.

Section three

A useful mental model: capability versus product

A skill

gives the AI a playbook

“When someone proposes a new AI use case, first determine what the system does. Check our registry. Check prohibited uses. Determine the governance tier. Identify required reviews. Produce the result in this format.”

That is enormously valuable. But it is primarily a behavioural specification. It tells an AI system: here is how we want this particular job performed.

A platform

packages the surrounding environment

Interfaces lawyers already understand, legal research sources, document repositories, matter organisation, integrations, permissions, collaboration, institutional knowledge, workflow builders, analytics, auditability, deployment support, security controls, vendor support, and preconfigured legal experiences.

Harvey’s current platform demonstrates this broader product approach, and Legora likewise describes its platform as connecting legal tools and workflows into a broader environment for legal work.

Skill: here is how to perform this job.
Platform: here is the environment in which thousands of people can actually perform this work.

Section four

But the distinction is getting blurrier

This is important. It would be misleading to teach that “Claude is just the model and Harvey is the application.” That description is becoming outdated.

Anthropic now describes a legal ecosystem involving connectors, skills, plugins, subagents, APIs, enterprise controls, and workplace integrations — not merely access to a foundation model. At the same time, Harvey and Legora increasingly expose configurable agents and workflows rather than only fixed software features. Harvey now describes purpose-built agents that can execute legal work, while Legora explicitly offers both agentic Workflows and reusable Skills within its environment.

More packagedMore configurable
  • Harvey and Legora workflows
  • Claude plus skills and plugins

Except even that is oversimplified. Each company is moving in both directions. The more useful competitive question is becoming:

Who provides the best combination of intelligence, workflow design, legal data, institutional knowledge, integration, user experience, governance, reliability, and deployment?

That is a much more interesting question than simply asking whose underlying model is smartest.

Part two

What a SKILL.md file actually is

Open the machine. A skill file has exactly two parts, and neither of them is code.

Section five

Now examine Anthropic’s AI governance legal plugin

The repository itself provides an important clue about how Anthropic thinks about the architecture. Its repository guidance describes the project as primarily involving prompt content — skills, agents, hooks, plugin metadata, and configuration — rather than conventional application code.

The repository layout identifies individual skill entrypoints at a predictable path, alongside plugin configuration, connectors, agents, and other components:

the shape of a plugin
ai-governance-legal/
  .claude-plugin/        # plugin metadata
  CLAUDE.md              # the practice profile the skills read
  references/            # knowledge the skills consult
  skills/
    <name>/SKILL.md     # one skill, one job

And AI Governance Legal is not one enormous skill. It contains separate jobs, each with its own folder and its own SKILL.md:

A terminology note. AIA means AI impact assessment, so aia-generation means, essentially, “generate an AI impact assessment.” That unusual-looking name is intentional, not a typo: it is the actual skill and directory name in the repository.

The use-case-triage skill handles one job: triaging a proposed AI use and determining the governance path. The aia-generation skill owns another job: conducting a more structured AI impact assessment, including intake, risk analysis, regulatory classification, policy comparison, and recommendations.

That separation is intentional. And it teaches us our first major skill-design lesson:

A sophisticated AI system is often better designed as several small skills than as one enormous prompt.

Section six

What exactly is a SKILL.md file?

Let’s demystify the filename. .md simply means Markdown, a way of writing formatted documents using ordinary text:

markdown
# Big heading

## Smaller heading

- bullet
- bullet

**bold text**

You do not need special software to understand a Markdown file. It opens in VS Code, Notepad, TextEdit, GitHub, or almost any plain-text editor. There is no mysterious AI programming language hidden inside it. Anthropic itself describes simple skills as Markdown-based workflows; more advanced skills can also include executable scripts.

A simplified skill might look something like this:

SKILL.md — teaching illustration
---
name: use-case-triage
description: >
  Classify proposed AI use cases and identify
  governance requirements and next steps.
---

# Purpose

Determine the governance path for a proposed AI use.

# Workflow

1. Understand the proposed use.
2. Check existing policy.
3. Check prohibited uses.
4. Determine the risk tier.
5. Identify required reviews.
6. Produce a structured result.

# Output

Include:
- classification
- rationale
- required conditions
- responsible owner
- next action

# Boundaries

Do not treat the assessment as final organizational approval.

A teaching simplification, not a verbatim reproduction of Anthropic’s file — but it demonstrates the basic anatomy.

Section seven

Anatomy of the file

A SKILL.md file contains two different kinds of information.

1. YAML frontmatter A small “label card” for the skill: what is this skill, and when might the system need it?
2. Markdown body The instructions for doing the job: now that you have chosen this skill, here is how to perform it.

If those terms sound technical, don’t worry. The easiest way to think about them is that YAML tells the system what the skill is, and Markdown tells the system how the skill works. Let’s unpack that one piece at a time.

Section eight

First: what is YAML?

YAML is a simple way of writing structured information in plain text. That sounds much more technical than it really is. Imagine the label on a file folder: a name, and a purpose. YAML lets us express that same kind of information in a predictable format that software can recognise:

yaml
name: ai-project-triage
description: Classify proposed AI projects and identify required governance steps.

The colon separates the name of the field from the information stored in it — label: value.

For the simple YAML used in a skill, you do not need to learn a programming language.

Section nine

So what is “frontmatter”?

Frontmatter is a small block of information placed at the very beginning of a document. Think of it as the information printed on the outside of the folder before you open it. In a skill, it might look like this:

the frontmatter block
---                          ← start of frontmatter
name: ai-project-triage
description: >
  Classify proposed organizational AI projects
  and identify required governance steps. Use
  when someone asks whether an AI use is permitted,
  prohibited, or requires additional review.
---                          ← end of frontmatter

After that comes the regular Markdown document containing the workflow.

Section ten

And what does “metadata” mean?

You may also hear the information in that top section described as metadata. That is another technical-sounding word with a simple meaning: metadata is information about something.

A book contains the actual story. Information about the book is its title, author, and publication year. A photograph has an image; information about the photograph might be the date taken, the camera, the location, and the file size. Likewise, the YAML at the top of our skill contains information about the skill. The actual instructions for performing the work come later.

Section eleven

What does the > mean?

You may notice description: > and wonder why that little > is there. It tells YAML that the description continues onto the indented lines below. So a description broken across four lines is still one description — it is simply set out so that a human can read it more comfortably.

You do not need to memorise YAML syntax to design a skill. The important point is understanding why this information exists.

Section twelve

Why does that tiny description matter so much?

Before the AI follows a skill’s detailed instructions, the system first has to decide: is this the right skill for this request? A skill’s metadata — especially its name and description — helps determine whether the skill should be selected. Once selected, the detailed instructions in SKILL.md become available.

This is why a vague description creates problems. description: Helps with AI governance. sounds reasonable to a human, but it gives the system very little help: almost anything could qualify as “AI governance.” Compare:

a description that can be matched
description: >
  Classify proposed organizational AI uses as
  approved, conditional, prohibited, or requiring
  further review. Use when a user asks whether
  an AI system may be used, what approvals are
  necessary, or what governance process applies.

Now the system has recognisable signals:

  1. A user asks: “Can we use this AI tool?” · “Does this project need approval?” · “What review does this AI system need?”
  2. The description matches those words
  3. Consider the AI project triage skill

The YAML description is the sign on the specialist’s door. It tells the system: this specialist handles these kinds of problems.

Section thirteen

Think of the description as the receptionist

Imagine an organisation with ten specialists. Someone walks through the door and says: “Marketing wants to upload customer interviews into an AI transcription service. Can we do that?”

Before anyone performs the work, somebody has to decide where the question belongs. AI inventory? No. Policy drafting? No. Impact assessment? Maybe later. Vendor AI review? Possibly later. Use-case triage? Yes. That routing decision happens before the detailed workflow begins.

Descriptions are not merely marketing copy. They help route work to the correct skill.

Which gives us a useful distinction: the description answers “what kinds of problems belong here?”, and the skill instructions answer “now that the problem is here, how should we solve it?”

Section fourteen

Part two of the file: the Markdown instructions

Once the skill has been selected, the Markdown body tells the AI how to perform the job.

the body of a skill
# Purpose

Provide fast, consistent governance triage.

## Step 1 — Understand the use case

Determine:
- what the AI does
- who is affected
- what data is involved
- whether human review exists

## Step 2 — Check policy

Read `references/governance-policy.md`.

## Step 3 — Check prohibitions

If a prohibited use applies, stop and explain why.

## Step 4 — Classify

Choose:
- Approved
- Conditional
- Prohibited
- Insufficient information

## Step 5 — Produce the output

Use the required output template.

Now the file is behaving almost like a small program. Not computer code exactly — but it has an input, a procedure, conditions, branches, and an output.

A well-designed skill is a small program written partly in natural language.

Part three

Design lessons from the plugin

Where a job ends, what stays out of the file, and what changes from one organisation to the next.

Section fifteen

Forensics on Anthropic’s triage skill

The use-case-triage skill handles the kind of hallway question that organisations constantly receive: “Can we just use AI for this?” Instead of answering that question informally every time, the skill turns it into a repeatable governance workflow. Conceptually, the process looks something like this:

  1. A request arrives
  2. Understand the use case
  3. Consult organisational context
  4. Check the use-case registry
  5. Check the red lines
  6. Determine a classification
    • approved
    • conditional
    • not approved
  7. Identify requirements
  8. Route the next action

The skill does not try to own every possible step after triage. If deeper review is necessary, another workflow can take over. That is excellent skill design, and it gives us another principle:

A skill should know both what job it owns and where that job ends.

Section sixteen

Why not put everything into one SKILL.md?

Because then you get the mega skill: AI governance and privacy and contract review and impact assessments and vendor review and regulatory research and policy drafting and litigation and employment and IP and research, all in one file.

At first this seems convenient — “let’s create one legal skill that knows everything!” But several problems appear at once. The instruction file becomes enormous. The AI has more irrelevant instructions competing for attention. Routing becomes fuzzy. Testing becomes difficult. Updates become risky. Responsibility between workflows becomes unclear.

Instead, a small router hands off to a triage skill, an assessment skill, a vendor skill, and a policy skill — each with a recognisable job. That modularity is one of the strongest lessons from this case.

Section seventeen

SKILL.md should be a control plane, not a textbook

A common beginner instinct is: “I have a 70-page AI policy. I’ll paste the entire thing into SKILL.md.” Don’t.

The skill should contain the instructions necessary to run the workflow. Large bodies of information that are needed only in particular situations can live in supporting resources:

one skill folder
ai-project-triage/
│
├── SKILL.md
│
├── references/
│   ├── governance-policy.md
│   ├── prohibited-uses.md
│   └── escalation-rules.md
│
├── scripts/
│   └── validate-output.py
│
└── assets/
    └── assessment-template.docx

The SKILL.md might simply say: before classifying a use case, read references/prohibited-uses.md; if the case requires escalation, consult references/escalation-rules.md.

This progressive structure is intentional: metadata helps determine whether the skill applies, SKILL.md provides the essential workflow, and supporting resources can be consulted when they become relevant.

SKILL.md is the control panel, not the warehouse.

Section eighteen

Four different things beginners often mix together

SKILL.md — procedure How to perform a job: check policy, identify risks, classify, produce this output.
references/ — knowledge The information needed to perform the job: here is our actual policy.
scripts/ — deterministic computation Code for operations that must be exact: validate these 5,000 records against the required schema.
assets/ — reusable output material Things used in the final deliverable: use this Word template for the report.

Don’t make SKILL.md carry all four jobs.

Section nineteen

Another forensic clue: configuration is separated from workflow

Anthropic’s AI Governance Legal design also separates organisational configuration from the generic workflow. This is particularly clear in the aia-generation skill — again, AIA means AI impact assessment.

Anthropic describes this skill as conducting a structured AI impact assessment, including risk analysis, regulatory classification, policy comparison, and recommendations. It also draws on an organisation’s configured “house style” rather than assuming every organisation conducts an assessment identically.

SkillI know how to conduct an AI impact assessment.
Organisation profileHere is how our organisation evaluates and documents risk.
Current matterHere is the AI system we are assessing.
ResultAn organisation-specific AI impact assessment.

This is a reusable pattern worth stealing. The skill contains the method. The organisation supplies the configuration. The current matter supplies the facts.

Section twenty

Build an onboarding skill when configuration matters

Anthropic includes a cold-start-interview capability for a reason. Before all of the other workflows can consistently reflect an organisation, something has to establish the organisation’s working context: its risk posture, policies, jurisdictions, escalation contacts, approved and prohibited uses, assessment format, vendor positions, and sign-off process.

Anthropic’s quick-start materials describe these setup interviews as creating a practice profile that other skills can then read:

  1. Setup interview
  2. An organisational profile is written down
  3. Every other skill reads it
    • triage
    • impact assessment
    • vendor review

That is much better than teaching every individual skill the organisation’s entire history. And it reveals another powerful design pattern:

Sometimes the first skill you need is not a task skill. It is a configuration skill.

Section twenty-one

The three-layer rule for designing your own skill

Layer 1 — Trigger

When should this skill run? Put that primarily in the description. A user says “Can we use AI to screen applicants?” and the triage skill should be the one that answers.

Layer 2 — Workflow

What sequence should the AI follow? Put that in SKILL.md: understand the use, check policy, check red lines, classify, identify conditions, produce the output.

Layer 3 — Resources

What does the AI need to consult or use? Put those in supporting files or connected systems: policy, regulations, templates, schemas, scripts, examples.

Which gives us: trigger → skill → resources → output.

Section twenty-two

A teaching template for a good skill

Here is a simplified example you could use as a starting point.

ai-project-triage/SKILL.md
---
name: ai-project-triage
description: >
  Classify proposed organizational AI projects
  and identify required governance steps. Use
  when a user asks whether an AI use is permitted,
  what approvals are required, or whether an
  additional privacy, security, legal, or impact
  review is necessary.
---

# Objective

Determine the appropriate governance path for
a proposed AI use.

# Required context

Before classification, determine:

- What will the AI do?
- Who is affected?
- What data will it process?
- What happens because of its output?
- Is there human review?
- Which vendor or model is involved?

# Workflow

1. Understand the use case.
2. Read `references/governance-policy.md`.
3. Check prohibited uses first.
4. Check previously approved use cases.
5. Determine governance tier.
6. Identify required reviews.
7. Produce the required output.

# Stop conditions

If essential information is missing:
- gather only the missing information.

If a prohibited-use rule applies:
- stop the ordinary workflow;
- identify the controlling policy;
- explain the escalation path.

# Output

## Use case

[one-sentence summary]

## Classification

[Approved / Conditional / Prohibited /
Insufficient Information]

## Basis

[short explanation]

## Required actions

| Action | Owner |
|---|---|

## Next step

[recommended workflow]

# Boundaries

Do not represent the classification as final
organizational approval when human sign-off is
required.

The interesting part isn’t the prose. It’s the architecture: trigger, context, procedure, branching, stop condition, output contract, boundary. Those are the building blocks.

Section twenty-three

Notice what we deliberately left out

We did not put these into the skill: the complete EU AI Act, the entire company AI policy, 600 approved vendors, 50 historical impact assessments, the security architecture, all of privacy law, or every output example.

Those things might still be useful. But they belong in the appropriate place — reference files, connected data systems, research tools, databases, other skills, or external applications. Which leads to one of the most useful rules in skill design:

Put the procedure in the skill. Put the library in the library.

Part four

Back to the market, and a checklist

What an open skill proves, what it does not, and twelve questions to ask of any skill you meet.

Section twenty-four

And this brings us back to Harvey and Legora

Now we can answer the original question more precisely. A sophisticated SKILL.md can encode something valuable: institutional legal procedure. That is significant. It means firms can increasingly express portions of their expertise as reusable AI workflows.

But legal AI platforms are selling considerably more than a prompt or a Markdown file. They are packaging combinations of:

Harvey’s current offering demonstrates this kind of bundled approach, combining agents, research, document infrastructure, knowledge resources, collaboration, workflows, integrations, and enterprise controls. Legora similarly combines agents and workflows with research, drafting, review, database search, institutional materials, permissions, and other legal tools. Meanwhile, Anthropic is moving upward from the foundation-model layer through skills, plugins, connectors, subagents, workplace integrations, APIs, and enterprise infrastructure.

So there is real competitive overlap. But:

An open legal skill demonstrates that legal workflow knowledge can be encoded. It does not demonstrate that every other layer of a legal technology platform has become unnecessary.

Section twenty-five

In fact, skills may make legal platforms more interesting

There is another possible outcome. Skills could increasingly become a kind of workflow layer through which organisations express how they want AI-assisted work performed. Imagine a firm develops its own our-nda-playbook, our-due-diligence-method, our-ai-governance-triage, our-privacy-review, and our-client-alert-style.

The strategically important asset may increasingly become the firm’s encoded way of working rather than simply the prompt box through which it accesses a model. Then the platform question becomes: where can our institutional workflows run best? That might ultimately involve Claude, ChatGPT, Harvey, Legora, an internal application, or some combination.

This is an inference about where the architecture could lead, not a claim that today’s products already offer interchangeable or fully portable skills.

In fact, Legora now also uses the term Skills for reusable instructions that encode a firm’s processes and standards inside its own agent environment. That convergence makes the underlying idea even more important. The terminology and file formats may differ; the architectural question remains:

How do we encode institutional expertise so that an AI can apply it consistently?

Section twenty-six

The larger lesson for skill designers

Anthropic’s AI Governance Legal project is useful as a teaching example precisely because the interesting part is not the legal prose. The interesting part is the decomposition.

Domain AI governance
Jobs inventory · triage · assessment · vendor review · policy analysis · monitoring
Individual skills trigger · workflow · branches · resources · outputs · boundaries · handoffs

That is the transition from “write a good prompt about AI governance” to “design a reusable AI system for doing AI-governance work.” And that is what skill design really is.

Section twenty-seven

The forensic checklist

When studying any skill — including the ones on this site — ask these questions.

1. Trigger
What kinds of requests should activate it?
2. Job
What single recognisable job does it own?
3. Inputs
What information must exist before work begins?
4. References
What knowledge should be consulted rather than baked into the skill?
5. Workflow
What happens first, second, and third?
6. Branches
Where can the workflow take different paths?
7. Stop conditions
When should automatic processing stop?
8. Output contract
What exactly should a successful result contain?
9. Boundary
What is the skill specifically not authorised to do?
10. Handoff
Which skill or human takes over next?
11. Configuration
Which parts should change from organisation to organisation?
12. Platform dependencies
What requires tools, data, integrations, or infrastructure beyond the skill itself?

That last question is especially important. It prevents us from confusing a great skill with a complete product — and that distinction explains a great deal about the emerging legal AI market.

Section twenty-eight

The simplest way to remember all of this

If the technical vocabulary starts to blur together, come back to this:

  1. YAML — what is this?
  2. Description — when should I use it?
  3. The SKILL.md body — how do I do the job?
  4. References — what information do I need?
  5. Scripts — what should code do reliably?
  6. Assets — what materials do I use in the output?
  7. Platform — where does all of this operate at scale?

Find the right skill. Follow the right process. Consult the right information. Produce the right result.

That is the core idea behind skill design.

The source

Read the repository yourself

Everything above is a reading of a public, Apache-2.0 licensed project: Anthropic’s Claude for Legal, and the ai-governance-legal plugin inside it. Every skill discussed here is a plain Markdown file you can open in a browser. Go and look at one.

Independent case study. Not affiliated with or endorsed by Anthropic.

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Robert Crown Law Library · last reviewed August 2026.