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.

The Warrant catalog on APIs.io includes 1 Spectral governance ruleset.

Warrant’s developer surface includes authentication, documentation, engineering blog, and 10 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

27.3/100 thin ▬ flat Agent 19/100 agent aware Heartbeat 5/100 dormant saas Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessFreemiumSelf serve⚡ Free to try

1 published contract

Access Control Authorization Fine-Grained Authorization FGA RBAC ReBAC ABAC Zanzibar Permissions Open Source Retired

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Cybersecurity Management

BC-620

CheckRoles & PermissionsWarrants

POST /v1/roles POST /v1/roles/{roleId}/permissions/{permissionId} POST /v1/users POST /v1/warrants

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 27.3/100 · thin

Contract Quality 8.3 / 19

Developer Ergonomics 4.7 / 15

Access Clarity 1.2 / 15

Operational Transparency 1.0 / 10

Contract Governance 1.2 / 9

Discoverability 5.0 / 8

Regulatory Posture 1.8 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 19/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 0 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Request/Response Examples +7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document

10 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Access Clarity scores 7.9 — up to +18.4 composite points
Contract Quality scores 44.4 — up to +13.9 composite points
Developer Ergonomics scores 31.0 — up to +13.8 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/warrant-dev/apis.yml: open an issue on github.com/api-evangelist/warrant-dev to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

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.

OpenAPI

measured — observed by APIs.io (published)

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 6

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Warrant Check API

OPEN COLLECTION

Warrant Check Object Types API

OPEN COLLECTION

Warrant Check Objects API

OPEN COLLECTION

Warrant Check Roles and Permissions API

OPEN COLLECTION

Warrant Check Warrants API

OPEN COLLECTION

Warrant API (Retired)

OPEN COLLECTION

Warrant API pricing

Not yet checked against Warrant's own pricing page. Compiled by API Evangelist on 2026-07-11 from warrant.dev/; confirm before you rely on a figure. A free plan or tier is listed.

Plan	Price
Open Source (Self-Hosted) free	—
Warrant Cloud - Free (Retired) free	—
Warrant Cloud - Usage (Retired) usage	—
Enterprise / Custom (Retired) enterprise	—

Plan details, limits and sources →

Rate limits

Authorization Check Requests: not published requests
Management API Requests: not published requests
Self-Hosted Throughput: hardware-bound requests

Compiled by API Evangelist, not yet checked against Warrant's documentation. Rate-limit details →

Pricing Plans 1

Published pricing tiers and plan structures.

Warrant Dev Plans Pricing

4 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Warrant Dev Rate Limits

3 limits

RATE LIMITS

Service Levels 1

Uptime the provider promises or reports, as SLA4OAI. Read from its own pages; APIs.io runs no monitors.

Warrant

SLA

FinOps 1

Cost, billing, and metering signals for API financial operations.

Warrant Dev Finops

FINOPS

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Warrant API Rules

62 rules · 58 errors 2 warnings 2 info

SPECTRAL

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Warrant Dev Authentication

apiKey · 1 scheme

SECURITY

Warrant Dev Domain Security

DNSSEC · DMARC

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Warrant Dev Agentic Access

29 operations · 17 acting

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Operate 1

Status, limits, changes, and where to get help

RateLimits

RateLimits

Commercial 2

Pricing, plans, and the legal terms of use

Plans

Plans

FinOps

FinOps

Company 3

The organization behind the API

LinkedIn

Website

Website

Blog

Blog

Other 2

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

PublicAPIsListing

PublicAPIsListing

Source (apis.yml)

aid: warrant-dev
url: https://raw.githubusercontent.com/api-evangelist/warrant-dev/refs/heads/main/apis.yml
name: Warrant
kind: company
description: 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.
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: false
  label: Hosted service · you call their endpoint
  confidence: medium
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  gated: none
  gated_source:
  - onboarding
  label: Freemium · Self-serve signup
  confidence: medium
  source:
  - plans
  - authentication
  generated: '2026-11-06'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/warrant-dev.png
tags:
- Access Control
- Authorization
- Fine-Grained Authorization
- FGA
- RBAC
- ReBAC
- ABAC
- Zanzibar
- Permissions
- Open Source
- Retired
tags_raw:
- Access Control
- Authorization
- Fine-Grained Authorization
- FGA
- RBAC
- ReBAC
- ABAC
- Zanzibar
- Permissions
- Open Source
- Retired
- Open-Source
created: '2026-07-11'
modified: '2026-08-08'
specificationVersion: '0.23'
apis:
- aid: warrant-dev:warrant-dev-check-api
  name: Warrant Check API
  description: Real-time access checks and relationship queries.
  humanURL: https://github.com/warrant-dev/warrant
  baseURL: https://api.warrant.dev/v1
  tags:
  - Check
  properties:
  - type: OpenAPI
    url: openapi/warrant-dev-check-api-openapi.yml
  - type: Documentation
    url: https://github.com/warrant-dev/warrant
  - type: APIReference
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/warrants
  - type: Documentation
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/resource-types
- aid: warrant-dev:warrant-dev-object-types-api
  name: Warrant Object Types API
  description: The authorization model - object types and their relations.
  humanURL: https://github.com/warrant-dev/warrant
  baseURL: https://api.warrant.dev/v1
  tags:
  - Object Types
  properties:
  - type: OpenAPI
    url: openapi/warrant-dev-object-types-api-openapi.yml
  - type: Documentation
    url: https://github.com/warrant-dev/warrant
  - type: APIReference
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/warrants
  - type: Documentation
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/resource-types
- aid: warrant-dev:warrant-dev-objects-api
  name: Warrant Objects API
  description: Resources and subjects that participate in the authorization model.
  humanURL: https://github.com/warrant-dev/warrant
  baseURL: https://api.warrant.dev/v1
  tags:
  - Objects
  properties:
  - type: OpenAPI
    url: openapi/warrant-dev-objects-api-openapi.yml
  - type: Documentation
    url: https://github.com/warrant-dev/warrant
  - type: APIReference
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/warrants
  - type: Documentation
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/resource-types
- aid: warrant-dev:warrant-dev-warrants-api
  name: Warrant Warrants API
  description: Relationship tuples (access rules) between subjects and objects.
  humanURL: https://github.com/warrant-dev/warrant
  baseURL: https://api.warrant.dev/v1
  tags:
  - Warrants
  properties:
  - type: OpenAPI
    url: openapi/warrant-dev-warrants-api-openapi.yml
  - type: Documentation
    url: https://github.com/warrant-dev/warrant
  - type: APIReference
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/warrants
  - type: Documentation
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/resource-types
- aid: warrant-dev:warrant-dev-roles-permissions-api
  name: Warrant Roles & Permissions API
  description: RBAC and entitlements convenience surface (roles, permissions, users, tenants, features, pricing tiers).
  humanURL: https://github.com/warrant-dev/warrant
  baseURL: https://api.warrant.dev/v1
  tags:
  - Roles & Permissions
  properties:
  - type: OpenAPI
    url: openapi/warrant-dev-roles-permissions-api-openapi.yml
  - type: Documentation
    url: https://github.com/warrant-dev/warrant
  - type: APIReference
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/warrants
  - type: Documentation
    url: https://workos.com/docs/fga
  - type: Documentation
    url: https://workos.com/docs/fga/resource-types
common:
- type: CapabilityMap
  url: capabilities/warrant-dev-capability-edges.yml
  name: Warrant Business Capability Map
- type: AgenticAccess
  url: agentic-access/warrant-dev-agentic-access.yml
- type: Authentication
  url: authentication/warrant-dev-authentication.yml
- type: DomainSecurity
  url: security/warrant-dev-domain-security.yml
- type: GitHubOrganization
  url: https://github.com/warrant-dev
- type: LinkedIn
  url: https://www.linkedin.com/company/warrant-dev
- type: Website
  url: https://warrant.dev
- type: Documentation
  url: https://workos.com/docs/fga
- type: Plans
  url: plans/warrant-dev-plans-pricing.yml
- type: RateLimits
  url: rate-limits/warrant-dev-rate-limits.yml
- type: FinOps
  url: finops/warrant-dev-finops.yml
- url: https://blog.warrant.dev
  type: Blog
- type: PublicAPIsListing
  url: https://github.com/public-apis/public-apis
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
x-merged-from:
- warrant

Warrant API — frequently asked questions

Does Warrant have an API?

Yes. APIs.io lists 5 APIs from Warrant, including Warrant Check API, Warrant Object Types API and Warrant Objects API, and 2 more.

Is there an OpenAPI specification for the Warrant API?

Yes. APIs.io indexes 5 OpenAPI specifications for Warrant, each linked for download from this page.

How do I authenticate with the Warrant API?

Warrant uses bearer-token authentication (apiKey · 1 scheme). The details are profiled on APIs.io as Warrant Dev Authentication.

How much does the Warrant API cost?

APIs.io lists 4 pricing plans for Warrant, with each plan's price, limits and inclusions under Pricing on this page.

Is the Warrant API ready for AI agents?

Warrant has a Kin Score of 27.3 out of 100 (thin) and an Agent Readiness score of 19.0 (agent-aware), scored by API Evangelist on 2026-11-06.

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