Zai

Zai (hellozai.com, formerly Assembly Payments / Assembly) is an Australian payments and Payments-as-a-Service provider headquartered in Melbourne. Zai gives platforms, marketplaces and vertical software companies a programmable way to onboard users, hold funds in managed wallet accounts, collect pay-ins (card, direct debit, BPAY, PayID), and disburse pay-outs across many parties in a single transaction flow. It is API-first: the Assembly API exposes wallet accounts, users, items, transactions, bank accounts, card accounts, fees, callbacks and batch disbursements, layered with Australia's New Payments Platform rails through dedicated Virtual Accounts / PayID and PayTo APIs, plus an Asynchronous API for long-running operations. Authentication is OAuth2 client-credentials (bearer tokens on PayTo), with a Live and Pre-live (sandbox) environment, webhooks with signature verification, and a developer dashboard. Positioned as the embedded-payments and marketplace-money-movement layer for the Australian market and platforms operating there.

Zai publishes 4 APIs on the APIs.io network, including Assembly API, Virtual Accounts and PayIDs API, PayTo API, and 1 more. Tagged areas include Payments, Australia, Payment Gateway, Payment Processing, and Marketplace Payments.

The Zai catalog on APIs.io includes 1 event-driven AsyncAPI specification.

Zai’s developer surface includes authentication, documentation, API reference, getting-started guide, pricing, engineering blog, support, and 28 more developer resources.

🌐 Visit website 📡 Source on GitHub
60.2/100 strong ▬ flat Agent 75/100 agent native Full breakdown ↓
scored 2026-07-27 · rubric v0.5
4 APIs 1 MCP Servers
PaymentsAustraliaPayment GatewayPayment ProcessingMarketplace PaymentsPayments-as-a-ServiceReal-Time PaymentsAccount-to-AccountOpen BankingPayToPayIDNPPDirect DebitDigital WalletsPayouts

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 60.2/100 · strong
Contract Quality 15.1 / 25
Developer Ergonomics 16.1 / 20
Commercial Clarity 10.5 / 20
Operational Transparency 3.8 / 13
Governance 0.0 / 12
Discoverability 10.0 / 10
Agent readiness — 75/100 · agent native
Machine-Readable Contract 18 / 18
Agentic Access Contract 15 / 15
MCP Server 12 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 8 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 6 / 6
Agent Skills 5 / 5
Well-Known Catalog 4 / 4
Consent & Bot Identity 0 / 3
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/zai: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 4

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

Zai Assembly API

Zai's core payments platform API. Onboard users, create and manage wallet accounts, items (transaction records), bank and card accounts, companies, fees, tokens, callbacks and b...

Zai Virtual Accounts and PayIDs API

Create and manage Virtual Accounts and PayIDs on the New Payments Platform (NPP), letting platforms receive real-time account-to-account pay-ins to uniquely addressable virtual ...

Zai PayTo API

Create and manage PayTo agreements (mandated real-time debits) and initiate payments against them over the New Payments Platform. OpenAPI 3.0.1, version 1.4-external, 10 documen...

Zai Asynchronous API

Asynchronous API for submitting long-running operations and retrieving their results without blocking, complementing the synchronous Assembly API. OpenAPI 3.0.0, version 1.0.0, ...

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

zai-mcp.yml

MCP SERVER

Event Specifications 1

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

Zai Webhooks

ASYNCAPI

Security Posture 2

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

Zai Authentication

http/oauth2 · 3 schemes

SECURITY

Zai Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Scopes 1

OAuth scopes governing access to this provider's APIs.

Zai Scopes

OAuth 2.0 · no documented scopes

0 scopes

SCOPES

Agentic Access 1

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

Zai Agentic Access

128 operations · 54 acting

128 operations · 54 acting

AGENTIC

Resources

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 SignUp
SignUp
 Sandbox
Sandbox

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess
AgenticAccess
 WellKnown
WellKnown
 MCPServer
MCPServer
 LLMsTxt
LLMsTxt
 AgentSkill
AgentSkill

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

Webhooks
Webhooks
 Conformance
Conformance
 ErrorCatalog
ErrorCatalog
 Lifecycle
Lifecycle
 Conventions
Conventions
 Webhooks
Webhooks
 DataModel
DataModel

Scroll for all 7

Build 4

SDKs, sample code, and the tooling you integrate with

Packages
Packages
 SDKs
SDKs
 ToolCrosswalk
ToolCrosswalk
 GitHubOrganization
GitHubOrganization

Access & Security 5

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity
 OAuthScopes
OAuthScopes
 Authentication
Authentication
 Authentication
Authentication
 Compliance
Compliance

Operate 2

Status, limits, changes, and where to get help

StatusPage
StatusPage
 Support
Support

Commercial 3

Pricing, plans, and the legal terms of use

Pricing
Pricing
 TermsOfService
TermsOfService
 PrivacyPolicy
PrivacyPolicy

Company 3

The organization behind the API

Website
Website
 Blog
Blog
 LinkedIn
LinkedIn

Source (apis.yml)

apis.yml Raw ↑ 
aid: zai
url: https://raw.githubusercontent.com/api-evangelist/zai/refs/heads/main/apis.yml
name: Zai
kind: company
description: 'Zai (hellozai.com, formerly Assembly Payments / Assembly) is an Australian payments and Payments-as-a-Service
  provider headquartered in Melbourne. Zai gives platforms, marketplaces and vertical software companies a programmable way
  to onboard users, hold funds in managed wallet accounts, collect pay-ins (card, direct debit, BPAY, PayID), and disburse
  pay-outs across many parties in a single transaction flow. It is API-first: the Assembly API exposes wallet accounts, users,
  items, transactions, bank accounts, card accounts, fees, callbacks and batch disbursements, layered with Australia''s New
  Payments Platform rails through dedicated Virtual Accounts / PayID and PayTo APIs, plus an Asynchronous API for long-running
  operations. Authentication is OAuth2 client-credentials (bearer tokens on PayTo), with a Live and Pre-live (sandbox) environment,
  webhooks with signature verification, and a developer dashboard. Positioned as the embedded-payments and marketplace-money-movement
  layer for the Australian market and platforms operating there.'
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/apis-json-logo.jpg
tags:
- Payments
- Australia
- Payment Gateway
- Payment Processing
- Marketplace Payments
- Payments-as-a-Service
- Real-Time Payments
- Account-to-Account
- Open Banking
- PayTo
- PayID
- NPP
- Direct Debit
- Digital Wallets
- Payouts
created: '2026-07-24'
modified: '2026-07-24'
specificationVersion: '0.19'
apis:
- aid: zai:zai-assembly-api
  name: Zai Assembly API
  description: Zai's core payments platform API. Onboard users, create and manage wallet accounts, items (transaction records),
    bank and card accounts, companies, fees, tokens, callbacks and batch transactions to collect pay-ins and disburse multi-party
    pay-outs across a marketplace or platform. OpenAPI 3.0.0, version 2.3, 89 documented paths, secured with OAuth2 client-credentials.
  humanURL: https://developer.hellozai.com/reference/overview
  baseURL: https://secure.api.promisepay.com
  tags:
  - Payments
  - Wallet Accounts
  - Marketplace
  - Pay-ins
  - Payouts
  properties:
  - type: OpenAPI
    url: openapi/zai-assembly-api.json
  - type: Documentation
    url: https://developer.hellozai.com/docs
  - type: APIReference
    url: https://developer.hellozai.com/reference/overview
  - type: Authentication
    url: https://developer.hellozai.com/reference/token
  - type: Overlay
    url: overlays/zai-assembly-api-overlay.yaml
- aid: zai:zai-virtual-accounts-payid-api
  name: Zai Virtual Accounts and PayIDs API
  description: Create and manage Virtual Accounts and PayIDs on the New Payments Platform (NPP), letting platforms receive
    real-time account-to-account pay-ins to uniquely addressable virtual accounts. OpenAPI 3.0.0, version 0.12-external, 8
    documented paths on the assemblypay.com host.
  humanURL: https://developer.hellozai.com/reference/overview-va
  baseURL: https://au-0000.api.assemblypay.com
  tags:
  - PayID
  - Virtual Accounts
  - NPP
  - Real-Time Payments
  properties:
  - type: OpenAPI
    url: openapi/zai-virtual-accounts-payid.json
  - type: Documentation
    url: https://developer.hellozai.com/reference/overview-va
  - type: APIReference
    url: https://developer.hellozai.com/reference/overview-va
  - type: Overlay
    url: overlays/zai-virtual-accounts-payid-overlay.yaml
- aid: zai:zai-payto-api
  name: Zai PayTo API
  description: Create and manage PayTo agreements (mandated real-time debits) and initiate payments against them over the
    New Payments Platform. OpenAPI 3.0.1, version 1.4-external, 10 documented paths, secured with bearer-token authentication.
  humanURL: https://developer.hellozai.com/reference/overview-1
  baseURL: https://au-0000.api.assemblypay.com/payto/
  tags:
  - PayTo
  - Mandates
  - NPP
  - Direct Debit
  - Real-Time Payments
  properties:
  - type: OpenAPI
    url: openapi/zai-payto.json
  - type: Documentation
    url: https://developer.hellozai.com/docs/payto
  - type: APIReference
    url: https://developer.hellozai.com/reference/overview-1
  - type: Overlay
    url: overlays/zai-payto-overlay.yaml
- aid: zai:zai-async-api
  name: Zai Asynchronous API
  description: Asynchronous API for submitting long-running operations and retrieving their results without blocking, complementing
    the synchronous Assembly API. OpenAPI 3.0.0, version 1.0.0, 3 documented paths, supporting OAuth2 client-credentials and
    basic authentication.
  humanURL: https://developer.hellozai.com/reference/async-overview
  baseURL: https://tnq.api.assemblypay.com/
  tags:
  - Async
  - Batch
  - Payments
  properties:
  - type: OpenAPI
    url: openapi/zai-async-api.json
  - type: Documentation
    url: https://developer.hellozai.com/reference/async-overview
  - type: APIReference
    url: https://developer.hellozai.com/reference/async-overview
  - type: Overlay
    url: overlays/zai-async-api-overlay.yaml
common:
- type: AgenticAccess
  url: agentic-access/zai-agentic-access.yml
- type: DomainSecurity
  url: security/zai-domain-security.yml
- type: OAuthScopes
  url: scopes/zai-scopes.yml
- type: Authentication
  url: authentication/zai-authentication.yml
- type: Website
  url: https://www.hellozai.com/
- type: DeveloperPortal
  url: https://developer.hellozai.com/
- type: Documentation
  url: https://developer.hellozai.com/docs
- type: APIReference
  url: https://developer.hellozai.com/reference/overview
- type: GettingStarted
  url: https://developer.hellozai.com/docs/developer-checklist
- type: Authentication
  url: https://developer.hellozai.com/reference/token
- type: Webhooks
  url: https://developer.hellozai.com/docs/webhooks
- type: StatusPage
  url: https://status.hellozai.com/
- type: Pricing
  url: https://www.hellozai.com/pricing
- type: Blog
  url: https://blog.hellozai.com/
- type: Support
  url: https://support.hellozai.com/
- type: SignUp
  url: https://dashboard.hellozai.com/
- type: TermsOfService
  url: https://www.hellozai.com/company/policies/terms-conditions
- type: PrivacyPolicy
  url: https://www.hellozai.com/company/policies/privacy-policy
- type: Compliance
  url: https://www.hellozai.com/company/compliance
- type: LinkedIn
  url: https://www.linkedin.com/company/hellozai/
- type: Packages
  url: packages/zai-packages.yml
- type: SDKs
  url: packages/zai-packages.yml
- type: WellKnown
  url: well-known/zai-well-known.yml
- type: MCPServer
  url: mcp/zai-mcp.yml
- type: ToolCrosswalk
  url: mcp/zai-tool-crosswalk.yml
- type: LLMsTxt
  url: llms/zai-llms.txt
- type: Conformance
  url: conformance/zai-conformance.yml
- type: ErrorCatalog
  url: errors/zai-error-codes.yml
- type: Lifecycle
  url: lifecycle/zai-lifecycle.yml
- type: Conventions
  url: conventions/zai-conventions.yml
- type: Webhooks
  url: asyncapi/zai-webhooks.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Sandbox
  url: sandbox/zai-sandbox.yml
- type: DataModel
  url: data-model/zai-data-model.yml
- type: GitHubOrganization
  url: https://github.com/AssemblyPayments
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com