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Affirm

Affirm is a buy-now-pay-later platform offering installment loans at point-of-sale via merchant SDKs and direct APIs. Public Series A through F-funded company.

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 Affirm the way a machine reads it — 115 machine-readable artifacts across 11 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 — Affirm scores 48.9/100 (developing), with a separate agent-readiness read of 54/100 (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 — 48.9/100 · developing
Contract Quality 21.0 / 25
Developer Ergonomics 2.2 / 20
Commercial Clarity 7.4 / 20
Operational Transparency 3.4 / 13
Governance 6.3 / 12
Discoverability 8.8 / 10
Regulatory · Payments 7.2 / 15
Agent readiness — 54/100 · 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 6 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3

How we profile Affirm

Each block below is one kind of artifact we hold for Affirm. 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 11

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.

Affirm Checkout API

Initialize and authorize Affirm checkout flows for online merchants.

Affirm Charges API

Capture, void, and refund Affirm charges; read transaction details.

Affirm Transactions API

Read transactions, settlements, and disputes.

Affirm Authorization API

Server-side operations for authorizing Affirm transactions after a customer completes the checkout flow and a checkout token is returned.

Affirm Cards API

Operations for managing virtual card numbers (VCN) issued via the Affirm Lite integration pattern.

Affirm Checkouts API

Operations for creating, retrieving, updating, and resending Affirm checkout sessions.

Affirm Disputes API

Operations for listing, retrieving, contesting, and closing payment disputes initiated by customers.

Affirm Promos API

Operations for retrieving dynamic promotional messaging and financing term information to display on merchant web pages.

Affirm Settlement Events API

Operations for listing settlement events and summaries that track disbursement activity.

Affirm Transaction Events API

Operations for listing transaction event records associated with transaction lifecycle changes.

Affirm Transactions API

Post-authorization transaction management operations including capture, void, and refund.

Scroll within the panel for all 11 ·

Open Collections 5

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).

Affirm Checkout API

OPEN COLLECTION

Affirm Direct API

OPEN COLLECTION

Affirm Disputes API

OPEN COLLECTION

Affirm Promos API

OPEN COLLECTION

Affirm Transactions API

OPEN COLLECTION

GraphQL 1

Where a provider ships GraphQL, the schema is the contract. We profile it alongside the REST surface so the whole interface is legible in one place.

GraphQL schemas published by this provider.

Affirm GraphQL Schema

This document describes the conceptual GraphQL schema for the Affirm Buy Now Pay Later (BNPL) platform. Affirm's production API is REST-based; this schema models the same domain...

GRAPHQL

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.

Affirm Plans Pricing

1 plans

PLANS

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.

Affirm Rate Limits

1 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals let a buyer model the financial operations of an API before it's live. We profile them for the same reason we profile pricing: the money is part of the contract.

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

Event Specifications 1

Not every API is request/response. AsyncAPI describes the event-driven and streaming side — the webhooks and channels — so the asynchronous half of the interface is documented the same way the synchronous half is.

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Affirm Webhooks

Affirm uses webhooks to notify merchant endpoints in real time when events occur during the customer checkout and prequalification flows. Webhooks are available to Key and Enter...

ASYNCAPI

Semantic Vocabularies 6

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.

Affirm Checkout Context

11 classes · 50 properties

JSON-LD

Affirm Context

0 classes · 9 properties

JSON-LD

Affirm Direct Context

3 classes · 23 properties

JSON-LD

Affirm Disputes Context

3 classes · 21 properties

JSON-LD

Affirm Promos Context

6 classes · 30 properties

JSON-LD

Affirm Transactions Context

4 classes · 22 properties

JSON-LD

Spectral Rules 3

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.

Affirm API Rules

8 rules · 1 errors · 7 warnings

SPECTRAL

Affirm API Rules

6 rules · 5 warnings

SPECTRAL

Affirm API Rules

42 rules · 16 errors · 24 warnings

SPECTRAL

JSON Schema 27

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.

Affirm Checkout

22 properties

JSON SCHEMA

Affirm Dispute

12 properties

JSON SCHEMA

Affirm Transaction

13 properties

JSON SCHEMA

AddressObject

6 properties

JSON SCHEMA

CheckoutRequest

15 properties

JSON SCHEMA

Checkout

18 properties

JSON SCHEMA

ContactObject

4 properties

JSON SCHEMA

DiscountObject

2 properties

JSON SCHEMA

ItemObject

7 properties

JSON SCHEMA

MerchantObject

5 properties

JSON SCHEMA

NameObject

3 properties

JSON SCHEMA

StoreObject

2 properties

JSON SCHEMA

Card

10 properties

JSON SCHEMA

FileObject

6 properties

JSON SCHEMA

Transaction

9 properties

JSON SCHEMA

Dispute

12 properties

JSON SCHEMA

EvidenceItem

4 properties

JSON SCHEMA

EvidenceRequest

6 properties

JSON SCHEMA

FinancingTerm

7 properties

JSON SCHEMA

OfferContent

3 properties

JSON SCHEMA

PromoConfig

7 properties

JSON SCHEMA

PromoContent

8 properties

JSON SCHEMA

PromoResponse

2 properties

JSON SCHEMA

SettlementEvent

7 properties

JSON SCHEMA

SettlementEventSummary

5 properties

JSON SCHEMA

TransactionEvent

8 properties

JSON SCHEMA

Transaction

13 properties

JSON SCHEMA

Scroll within the panel for all 27 ·

JSON Structure 27

JSON Structure captures the data shapes in a form built for tooling — a complement to JSON Schema that keeps the model machine-legible.

JSON Structure definitions describing this provider's data shapes.

Affirm Checkout Structure

22 properties

JSON STRUCTURE

Affirm Dispute Structure

12 properties

JSON STRUCTURE

Affirm Transaction Structure

13 properties

JSON STRUCTURE

Checkout Address Object Structure

6 properties

JSON STRUCTURE

Checkout Checkout Request Structure

15 properties

JSON STRUCTURE

Checkout Checkout Structure

18 properties

JSON STRUCTURE

Checkout Contact Object Structure

4 properties

JSON STRUCTURE

Checkout Discount Object Structure

2 properties

JSON STRUCTURE

Checkout Item Object Structure

7 properties

JSON STRUCTURE

Checkout Merchant Object Structure

5 properties

JSON STRUCTURE

Checkout Name Object Structure

3 properties

JSON STRUCTURE

Checkout Store Object Structure

2 properties

JSON STRUCTURE

Direct Api Card Structure

10 properties

JSON STRUCTURE

Direct Api File Object Structure

6 properties

JSON STRUCTURE

Direct Api Transaction Structure

9 properties

JSON STRUCTURE

Disputes Dispute Structure

12 properties

JSON STRUCTURE

Disputes Evidence Item Structure

4 properties

JSON STRUCTURE

Disputes Evidence Request Structure

6 properties

JSON STRUCTURE

Promos Financing Term Structure

7 properties

JSON STRUCTURE

Promos Offer Content Structure

3 properties

JSON STRUCTURE

Promos Promo Config Structure

7 properties

JSON STRUCTURE

Promos Promo Content Structure

8 properties

JSON STRUCTURE

Promos Promo Response Structure

2 properties

JSON STRUCTURE

Transactions Settlement Event Structure

7 properties

JSON STRUCTURE

Transactions Transaction Event Structure

8 properties

JSON STRUCTURE

Transactions Transaction Structure

13 properties

JSON STRUCTURE

Scroll within the panel for all 27 ·

Examples 27

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.

Scroll within the panel for all 27 ·

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.

Affirm Authentication

http · 1 scheme

SECURITY

Affirm Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Affirm Trust Center

SOC 2, PCI DSS

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.

Affirm Agentic Access

29 operations · 18 acting

29 operations · 18 acting

AGENTIC

Resources

Every other property we hold for Affirm — 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.

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

Build 1

SDKs, sample code, and the tooling you integrate with

Access & Security 3

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 2

The organization behind the API

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