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Login.gov

Login.gov is the U.S. federal government's secure single sign-on and identity verification service for the public, operated by the General Services Administration's Technology Transformation Services (GSA TTS). Relying parties — federal, and in some cases state and local — federate user authentication to Login.gov via OpenID Connect (iGov profile) or SAML 2.0, with support for IAL1 (auth-only) and IAL2 (identity-verified) assurance and AAL2 multi-factor authentication including phishing-resistant and PIV/CAC authenticators.

agent ready

Real signal across most facets with visible, nameable gaps — the contract exists but is thin, or the portal is good while governance and commercial terms are absent.

Kin Score

API Evangelist profiles Login.gov the way a machine reads it — 37 machine-readable artifacts across 7 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.

Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Login.gov scores 57.2/100 (developing), with a separate agent-readiness read of 48/100 (agent ready). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.

Kin Score

This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 57.2/100 · developing
Contract Quality 17.9 / 25
Developer Ergonomics 9.6 / 20
Commercial Clarity 6.3 / 20
Operational Transparency 2.7 / 13
Governance 10.4 / 12
Discoverability 10.0 / 10
Regulatory · Government & Public Sector 8.8 / 15
Agent readiness — 48/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 15 / 15
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

How we profile Login.gov

Each block below is one kind of artifact we hold for Login.gov. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.

APIs 7

Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.

Individual APIs this provider publishes, each with its own machine-readable definition.

Login.gov Authentication API

SAML SSO request endpoint.

Login.gov Authorization API

OAuth 2.0 authorization endpoint where the user authenticates.

Login.gov Discovery API

OIDC discovery and public key endpoints.

Login.gov Logout API

RP-initiated logout and session termination.

Login.gov Metadata API

SAML 2.0 IdP metadata.

Login.gov Token API

Token exchange using private_key_jwt or PKCE.

Login.gov UserInfo API

User attribute retrieval with a bearer access token.

Scroll within the panel for all 7 ·

Open Collections 2

Open, tool-agnostic collections carry the same runnable value as Postman without locking you to one client — the portable, forkable form of the same exercise.

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

Pricing Plans 1

Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the six things the Kin Score reads for commercial clarity.

Published pricing tiers and plan structures.

Rate Limits 1

Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.

Documented rate limits and quota policies.

Login Gov Rate Limits

0 limits

RATE LIMITS

Features 14

The notable capabilities this provider advertises, captured as structured features so they can be searched and compared instead of read one landing page at a time.

Notable capabilities this provider offers.

Single account for the public to access participating federal services
OpenID Connect (iGov profile) and SAML 2.0 federation
Authorization code flow with private_key_jwt or PKCE; implicit flow not supported
IAL1 (authentication only) and IAL2 (identity-verified) assurance levels
AAL2 with TOTP, SMS/voice, push, security keys, PIV/CAC, and platform passkeys
Phishing-resistant AAL2 variant and HSPD-12 (PIV/CAC) AAL2 variant
Identity proofing with optional facial-match step
Self-service Partner Portal (sandbox and production) for client registration and scope/cert management
JWKS endpoint with at-least-annual key rotation; SAML certs rotated yearly with year-versioned endpoints
{"User attributes scoped per OIDC scope/SAML attribute"=>"email, all_emails, name, address, birthdate, phone, SSN, verified_at, locale, x509 subject/issuer/presented"}
{"Built and operated in the open"=>"identity-idp (Ruby on Rails) and sample SP apps published under github.com/18F"}
English, Spanish, and French locales
Section 508 accessibility commitment; published privacy policy and PIA
Cost-recoverable funding model via Interagency Agreement (IAA); no public rate card

Scroll within the panel for all 14 ·

Semantic Vocabularies 1

JSON-LD contexts give the data shared meaning across APIs. We profile them because semantics are what let a machine reconcile 'customer' here with 'customer' somewhere else.

JSON-LD contexts and semantic vocabularies used across these APIs.

Login Gov Context

29 classes · 4 properties

JSON-LD

Spectral Rules 2

Governance rulesets we run against this provider's specs — the automated checks behind parts of the score. Profiling them makes the quality bar explicit and re-runnable, not a matter of opinion.

Login.gov API Rules

5 rules · 4 warnings

SPECTRAL

Login.gov API Rules

7 rules · 5 errors · 2 warnings

SPECTRAL

JSON Schema 2

Standalone JSON Schema definitions describe the data models behind the API. We profile them so the shapes are validatable on their own — useful long after a single request is forgotten.

Standalone JSON Schema definitions for this provider's data models.

Login.gov ID Token Claims

11 properties

JSON SCHEMA

Login.gov UserInfo

19 properties

JSON SCHEMA

Examples 3

Real request and response payloads are what turn a spec from abstract into obvious — and they're one of the twelve things an agent needs to call an API correctly on the first try.

Example request and response payloads for these APIs.

Security Posture 3

Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.

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

Login Gov Authentication

http · 1 scheme

SECURITY

Login Gov Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Login Gov Vulnerability Disclosure

Hackerone · security.txt · contact published

SECURITY

Agentic Access 1

An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.

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

Login Gov Agentic Access

9 operations · 2 acting

9 operations · 2 acting

AGENTIC

Resources

Every other property we hold for Login.gov — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.

Get Started 4

Portal, sign-up, and the first successful call

Documentation 1

Reference material describing how the API behaves

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

Operate 3

Status, limits, changes, and where to get help

Commercial 2

Pricing, plans, and the legal terms of use

Company 2

The organization behind the API

Other 2

Properties that don't map to a standard resource type

← All providers · Data indexed from github.com/api-evangelist/login-gov · machine-readable index on apis.io