Westlaw API

Name: Westlaw API API
Brand: Westlaw API
Availability: InStock

★ Only Publicly Available OpenAPI DocumentData EnrichmentData TransformationapiKey4 EndpointsREST

For Agents

Search and retrieve cases, statutes, and full legal documents from Westlaw so an agent can ground legal answers in primary sources via four focused endpoints.

Quickstart

Get started with Westlaw API in minutes using your preferred integration method.

# Add to your MCP client config (Claude Desktop, Cursor, Windsurf)
{
  "jentic": {
    "url": "https://api.jentic.com/mcp",
    "auth": "oauth"
  }
}

# Then ask your agent:
"search Westlaw case law and statutes"

# → Jentic returns the GET /events tool with parameter schema, agent executes.

Capabilities

What an agent can do with Westlaw API API.

Search legal documents across Westlaw's corpus with POST /search

Retrieve a specific document by documentId for full-text legal citations

Search case law specifically through GET /cases for litigation research

Search statutes through GET /statutes for regulatory and compliance research

GET STARTED

Start building with Westlaw API API

Explore with Jentic

View OpenAPI Document

Jentic publishes the only available OpenAPI document for Westlaw API, keeping it validated and agent-ready.

Jentic publishes the only available OpenAPI specification for Westlaw API, keeping it validated and agent-ready. The Westlaw API from Clarivate provides programmatic access to legal research and analytics, exposing search and document-retrieval endpoints for cases, statutes, and full legal documents. It uses an Authorization-header API key and is targeted at legal-tech tools, in-house legal teams, and AI assistants that need to ground answers in primary legal sources rather than free-text scraping. The endpoint surface is intentionally small — search, retrieve, and filter by document type.

Use Cases

Patterns agents use Westlaw API API for, with concrete tasks.

★ Grounded legal research for AI assistants

An AI legal assistant calls POST /search with the user's natural-language question, gets back a ranked list of Westlaw documents, then calls GET /documents/{documentId} for the top results to extract authoritative passages. The assistant cites Westlaw as the source rather than hallucinating from training data, which is the difference between a usable legal tool and a liability.

Call POST /search with the query 'employment non-compete enforceability California', retrieve the top 3 documentIds, and pull each through GET /documents/{documentId}.

Litigation case-law lookup

A litigator preparing a brief calls GET /cases with the parties' names and a date range to find directly-on-point precedents, then pulls the full opinion through GET /documents/{documentId}. This replaces minutes of manual searching in the Westlaw web UI with a single API workflow that can also be scripted into a brief-preparation tool.

Call GET /cases with a party-name query and a date range covering the last 10 years, then retrieve the top result via GET /documents/{documentId}.

Regulatory monitoring across statutes

A compliance team polls GET /statutes regularly with a topic query (for example 'data privacy California') to surface newly enacted or amended statutes. New documentIds trigger a notification, and the full text is pulled via GET /documents/{documentId} for the compliance reviewer.

Call GET /statutes with topic='data privacy' and jurisdiction='California', diff against yesterday's documentId list, and forward new statutes to the compliance reviewer.

AI agent legal grounding via Jentic

A general-purpose AI agent connects to Westlaw through Jentic. When a user asks a legal question, the agent searches by intent ('search Westlaw case law'), loads the schema for POST /search, and executes the call. The user gets a citation-backed answer instead of a confidently wrong summary, and the API key never leaves the Jentic vault.

Through Jentic, search 'search Westlaw case law', load the schema for POST /search, and execute the call with the user's legal question as the query string.

Key Endpoints

4 endpoints — jentic publishes the only available openapi specification for westlaw api, keeping it validated and agent-ready.

METHOD

PATH

DESCRIPTION

POST

/search

Search legal documents

GET

/documents/{documentId}

Get a legal document by ID

GET

/cases

Search cases

GET

/statutes

Search statutes

POST

/search

Search legal documents

GET

/documents/{documentId}

Get a legal document by ID

GET

/cases

Search cases

GET

/statutes

Search statutes

Why though Jentic?

Three things that make agents converge on Jentic-routed access.

Credential isolation

The Westlaw API key is stored encrypted in the Jentic vault (MAXsystem). Jentic injects the Authorization header at execution time — the agent never sees the raw key.

Intent-based discovery

Agents search by intent (e.g. 'search Westlaw case law') and Jentic returns the matching Westlaw operation with its input schema, so the agent calls the right endpoint without browsing Clarivate's developer portal.

Time to first call

Direct Westlaw integration: 2-3 days including contract sign-off, key provisioning, and search/document wiring. Through Jentic: under an hour once the key is in the vault — search, load schema, execute.

Related APIs

Alternatives and complements available in the Jentic catalogue.

Alternative

UniCourt Legal Data API

Open-access US case law and court document API, free for many use cases

Choose CourtListener when budget rules out Westlaw or when public US federal case law is sufficient for the task.

Complementary

OpenAI API

LLM that summarises Westlaw documents into answers

Use OpenAI alongside Westlaw to convert retrieved case opinions into a plain-English answer with citations.

Complementary

Anthropic API

Long-context LLM useful for reasoning over multiple Westlaw opinions

Use Anthropic when the legal answer requires synthesising multiple long Westlaw documents into one analysis.

FAQs

Specific to using Westlaw API API through Jentic.

Why is there no official OpenAPI spec for Westlaw API?

Clarivate does not publish a public OpenAPI specification for Westlaw. Jentic generates and maintains this spec so that AI agents and developers can call Westlaw API via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.

What authentication does the Westlaw API use?

The Westlaw API uses an API key sent in the Authorization request header. Through Jentic, the key is stored encrypted in the MAXsystem vault and injected at execution time — the agent's context never holds the raw key.

Can I retrieve the full text of a case opinion or statute?

Yes. After calling /search, /cases, or /statutes to get a documentId, GET /documents/{documentId} returns the full document text. This is the canonical way to pull the primary source for citation in a brief or AI answer.

Can I search case law and statutes separately?

Yes. GET /cases is the dedicated case-law search endpoint and GET /statutes is the dedicated statute-search endpoint. POST /search performs a cross-document search across the full Westlaw corpus when the document type is not known in advance.

What are the rate limits for the Westlaw API?

The OpenAPI spec does not declare explicit rate limits. Clarivate gates Westlaw API access by contract, with per-account quotas. For production usage, add retry-with-backoff on 429 responses and confirm specific limits with your Clarivate account team.

How do I ground an AI agent's legal answers in Westlaw through Jentic?

Run pip install jentic, then have the agent search 'search Westlaw case law', load the schema for POST /search, execute the call with the user's question, and pull the top documents through GET /documents/{documentId}. Jentic resolves the API key automatically — the agent only sees the search results.