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Primer

Primer is a payment orchestration platform that enables merchants to build flexible payment flows across multiple processors through a single REST API integration. The platform provides intelligent routing, automatic fallback logic, fraud detection integrations, and a no-code Workflows builder for managing payment rules without engineering effort. Primer supports 60+ payment methods including cards, digital wallets, and regional alternatives such as iDEAL, Klarna, and Alipay. The platform delivers unified observability, reconciliation, and analytics across all connected payment providers, and processes billions of dollars monthly with 99.99% uptime.

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 Primer the way a machine reads it — 47 machine-readable artifacts across 5 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 — Primer scores 59.5/100 (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 — 59.5/100 · developing
Contract Quality 16.2 / 25
Developer Ergonomics 4.3 / 20
Commercial Clarity 9.5 / 20
Operational Transparency 8.9 / 13
Governance 10.4 / 12
Discoverability 10.0 / 10
Regulatory · Payments 9.1 / 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 Primer

Each block below is one kind of artifact we hold for Primer. 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 5

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.

Primer Client Session API API

The Client Session API API from Primer — 1 operation(s) for client session api.

Primer Dispute & Chargebacks Webhooks API

The Dispute & Chargebacks Webhooks API from Primer — 2 operation(s) for dispute & chargebacks webhooks.

Primer Payment Methods API API

The Payment Methods API API from Primer — 4 operation(s) for payment methods api.

Primer Payment Webhooks API

The Payment Webhooks API from Primer — 2 operation(s) for payment webhooks.

Primer Payments API API

The Payments API API from Primer — 8 operation(s) for payments api.

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.

Primer Plans Pricing

2 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.

Primer Rate Limits

3 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.

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.

Primer Context

16 classes · 27 properties

JSON-LD

Spectral Rules 1

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.

Primer API Rules

6 rules · 4 warnings

SPECTRAL

JSON Schema 5

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.

ClientSessionAPIRequest

8 properties

JSON SCHEMA

PaymentAPIResponse

18 properties

JSON SCHEMA

PaymentCaptureAPIRequest

5 properties

JSON SCHEMA

PaymentCreationAPIRequest

10 properties

JSON SCHEMA

PaymentRefundAPIRequest

5 properties

JSON SCHEMA

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 4

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.

Primer Authentication

apiKey · 1 scheme

SECURITY

Primer Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Primer Vulnerability Disclosure

disclosure policy published

SECURITY

Primer Trust Center

SOC 2, ISO 27001

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.

Primer Agentic Access

20 operations · 16 acting

20 operations · 16 acting

AGENTIC

Resources

Every other property we hold for Primer — 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 1

MCP servers, agent skills, and machine-readable catalogs

Design & Contract 2

Pagination, idempotency, versioning, errors, and events

Build 1

SDKs, sample code, and the tooling you integrate with

Operate 3

Status, limits, changes, and where to get help

Commercial 3

Pricing, plans, and the legal terms of use

Company 3

The organization behind the API

Other 1

Properties that don't map to a standard resource type

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