Warrant
Warrant was a centralized, fine-grained authorization (FGA) and access control service inspired by Google Zanzibar, exposing a real-time REST API to define an authorization model, store relationships (warrants) between objects, and run low-latency access checks and queries. It supported relationship-based (ReBAC), role-based (RBAC), and attribute-based (ABAC) access control, plus entitlements such as pricing tiers and feature gating. The core engine is open source (Apache-2.0, github.com/warrant-dev/warrant) and self-hostable. Warrant was acquired by WorkOS on 2024-04-23 and folded into WorkOS FGA; the standalone hosted Warrant service (api.warrant.dev) and the Warrant-based WorkOS FGA were deprecated and sunset on 2025-11-15. This entry documents Warrant's public API surface historically - the endpoints modeled here reflect the documented api.warrant.dev v1/v2 API and are RETIRED. Current fine-grained authorization is offered through WorkOS; the open-source engine remains self-hostable.
Warrant publishes 5 API contracts indexed on the APIs.io network, including Check API, Object Types API, Objects API, and 2 more. Tagged areas include Access Control, Authorization, Fine-Grained Authorization, FGA, and RBAC.
Warrant’s developer surface includes authentication, documentation, engineering blog, and 10 more developer resources.
What this lets a business do 1
Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →
Kin Score
Standards implemented 1
Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.
APIs 5
Individual APIs this provider publishes, each with its own machine-readable definition.
Warrant Check API
Real-time access checks and relationship queries.
Warrant Object Types API
The authorization model - object types and their relations.
Warrant Objects API
Resources and subjects that participate in the authorization model.
Warrant Warrants API
Relationship tuples (access rules) between subjects and objects.
Warrant Roles & Permissions API
RBAC and entitlements convenience surface (roles, permissions, users, tenants, features, pricing tiers).
Open Collections 7
Open, tool-agnostic API collections (OpenAPI-derived and Bruno).
API Collection
OPEN COLLECTIONWarrant Check API
OPEN COLLECTIONWarrant Check Object Types API
OPEN COLLECTIONWarrant Check Objects API
OPEN COLLECTIONWarrant Check Roles and Permissions API
OPEN COLLECTIONWarrant Check Warrants API
OPEN COLLECTIONWarrant API (Retired)
OPEN COLLECTIONScroll for all 7
Pricing Plans 1
Published pricing tiers and plan structures.
Rate Limits 1
Documented rate limits and quota policies.
Warrant Dev Rate Limits
RATE LIMITSFinOps 1
Cost, billing, and metering signals for API financial operations.
Warrant Dev Finops
FINOPSSecurity Posture 2
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
Recommended x-agentic-access execution contracts for AI agents.
Resources
Documentation 1
Reference material describing how the API behaves
Agent Surfaces 1
MCP servers, agent skills, and machine-readable catalogs
Build 1
SDKs, sample code, and the tooling you integrate with
Access & Security 2
Authentication, authorization, and security posture
Operate 1
Status, limits, changes, and where to get help
Commercial 2
Pricing, plans, and the legal terms of use
Company 3
The organization behind the API
Other 2
Properties that don't map to a standard resource type
Source (apis.yml)
Work with this as data
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