The most complete open-source US primary law API with 3.9M+ sections across 52 jurisdictions
Vaquill AI offers what it calls the most complete open-source US primary law API. The numbers on the homepage are specific: 3.9 million-plus primary law sections across 52 US jurisdictions, accessible through REST and MCP interfaces. The email contact@vaquill.ai is publicly listed.
This is a data infrastructure product, not a consumer tool. The target users are developers building legal tech applications: contract analysis tools, compliance checkers, legal research platforms, and AI assistants that need to reference specific statutes. Getting US legal data is notoriously difficult. Court websites are fragmented across jurisdictions, formats are inconsistent, and commercial legal databases (Westlaw, LexisNexis) are expensive and closed.
An open-source API with 3.9 million sections solves the data acquisition problem. A developer building a legal AI tool can call Vaquill's API instead of scraping court websites or paying for commercial database access. The MCP interface means it works with AI agent frameworks out of the box, which is the right integration point for legal AI applications.
The "what builders are making" section on the homepage suggests they showcase use cases built on the API. The docs link indicates proper API documentation exists. For legal tech developers, the evaluation criteria are data coverage (does it include the jurisdictions and statute types you need), data freshness (how quickly are new laws added), and API reliability. The open-source nature means you can also self-host if the hosted API does not meet your reliability requirements.
What it is
The most complete open-source US primary law API with 3.9M+ sections across 52 jurisdictions
Pricing
Free
Primary category
Design
Source code
Closed source / hosted
Vaquill AI is one of many tools in its category. Before committing to it, weigh a few practical points that tend to decide whether a tool actually fits your work:
We describe Vaquill AI and its alternatives honestly so you can compare on substance. Browse the similar tools below to see how it stacks up against other options in the same category.
