Stax

Stax (formerly Fattmerchant) is an Orlando, Florida payments technology company that sells subscription-priced payment processing to small and large merchants (Stax Pay), embedded payments and merchant onboarding to SaaS platforms and ISVs (Stax Connect), compliant credit-card surcharging (CardX by Stax), automated subscription billing (Stax Bill), and full-stack processing for partners and ISOs (Stax Processing). Its public REST API at apiprod.fattlabs.com covers charges, credits, refunds and voids, stored payment methods and tokenization, customers, invoices and invoice schedules, payment links, catalog items, terminals and card-present devices, merchant enrollment and underwriting, disputes, statements and deposit reporting, teams, users and API keys, and merchant- and partner-level webhooks. Stax.js handles browser tokenization; iOS and Android SDKs cover card-present and Tap to Pay. Stax Payments, Inc. is a registered ISO/MSP of Fifth Third Bank and Synovus Bank and a registered partner/ISO of Elavon, Inc.

Stax publishes 23 APIs on the APIs.io network, including Admin API, Charge API, Credit API, and 20 more. Tagged areas include Payments, Payment Processing, Merchant Services, Embedded Payments, and ACH.

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

Stax’s developer surface includes documentation, API reference, getting-started guide, support, engineering blog, pricing, signup flow, and 37 more developer resources.

🌐 Visit website 📡 Source on GitHub

76.4/100 exemplar ▬ flat Agent 52/100 agent native Front door AI 1/6 silent Full breakdown ↓
scored 2026-09-20 · rubric v0.22.0

AccessPaid

1 APIs 1 MCP Servers

Payments Payment Processing Merchant Services Embedded Payments ACH Invoicing Subscription BillingSurchargingPoint-of-Sale Tokenization Financial-Services Fintech Card Present Merchant Onboarding

Kin Score

Kin Score How this is scored →
scored 2026-09-20 · rubric v0.22.0

Composite quality — 76.4/100 · exemplar

Contract Quality 12.6 / 19

Developer Ergonomics 11.0 / 15

Access Clarity 13.8 / 15

Operational Transparency 8.2 / 10

Contract Governance 1.6 / 9

Discoverability 5.7 / 8

Regulatory Posture 10.3 / 15

Create-or-Update Ergonomics 1.1 / 10

Agent readiness — 52/100 · agent native

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 6 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 9 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 6

Agent Skills 5 / 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

Regulatory Posture applies to this provider. Its tags matched the Payments 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/.

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 github.com/api-evangelist/stax: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 23

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

Stax Admin API

The Admin API from Stax — 1 operation(s) for admin.

Stax Charge API

The Charge API from Stax — 1 operation(s) for charge.

Stax Credit API

The Credit API from Stax — 1 operation(s) for credit.

Stax Customer API

The Customer API from Stax — 3 operation(s) for customer.

Stax Ephemeral API

The Ephemeral API from Stax — 1 operation(s) for ephemeral.

Stax File API

The File API from Stax — 5 operation(s) for file.

Stax File{id} API

The File{id} API from Stax — 1 operation(s) for file{id}.

Stax Forgot API

The Forgot API from Stax — 1 operation(s) for forgot.

Stax Invoice API

The Invoice API from Stax — 9 operation(s) for invoice.

Stax Item API

The Item API from Stax — 5 operation(s) for item.

Stax Merchant API

The Merchant API from Stax — 7 operation(s) for merchant.

Stax Payment Method API

The Payment Method API from Stax — 4 operation(s) for payment method.

Stax Query API

The Query API from Stax — 14 operation(s) for query.

Stax Reset API

The Reset API from Stax — 1 operation(s) for reset.

Stax Self API

The Self API from Stax — 4 operation(s) for self.

Stax Surcharge API

The Surcharge API from Stax — 1 operation(s) for surcharge.

Stax Team API

The Team API from Stax — 8 operation(s) for team.

Stax Terminal API

The Terminal API from Stax — 13 operation(s) for terminal.

Stax Transaction API

The Transaction API from Stax — 11 operation(s) for transaction.

Stax Underwriting API

The Underwriting API from Stax — 5 operation(s) for underwriting.

Stax Verify API

The Verify API from Stax — 1 operation(s) for verify.

Stax Webhook API

The Webhook API from Stax — 2 operation(s) for webhook.

Stax Webhookadmin API

The Webhookadmin API from Stax — 2 operation(s) for webhookadmin.

Scroll for all 23

MCP Servers 1

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

Stax Docs MCP Server

Stax hosts a remote MCP server at https://docs.staxpayments.com/mcp. It answered an anonymous initialize + tools/list on 2026-08-29 (protocolVersion 2025-06-18, serverInfo {name...

MCP SERVER

Pricing Plans 1

Published pricing tiers and plan structures.

Stax Plans Pricing

4 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Stax Rate Limits

4 limits

RATE LIMITS

Event Specifications 1

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

Stax Webhooks

ASYNCAPI

Security Posture 4

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

Stax Authentication

http · 3 schemes

SECURITY

Stax Domain Security

TLSv1.3 · DMARC

SECURITY

Stax Vulnerability Disclosure

Hackerone · security.txt · contact published

SECURITY

Stax Trust Center

trust center published

SECURITY

Agentic Access 1

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

Stax Agentic Access

133 operations · 79 acting · 2 human-in-the-loop

133 operations · 79 acting

AGENTIC

Resources

Get Started 5

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

SignUp

SignUp

Login

Sandbox

Sandbox

Documentation 3

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

OpenAPI

OpenAPI

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

MCPServer

LLMsTxt

AgentSkill

Design & Contract 8

Pagination, idempotency, versioning, errors, and events

Lifecycle

Conventions

Idempotency

ErrorCatalog

Webhooks

Components

DataModel

Conformance

Scroll for all 8

Build 6

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

DeclineCodes

ToolCrosswalk

Packages

SDKs

Examples

Access & Security 7

Authentication, authorization, and security posture

Authentication

Compliance

TrustCenter

SecurityTxt

VulnerabilityDisclosure

VulnerabilityDisclosure

Security

Security

DomainSecurity

DomainSecurity

Scroll for all 7

Operate 4

Status, limits, changes, and where to get help

Support

StatusPage

ChangeLog

RateLimits

Commercial 4

Pricing, plans, and the legal terms of use

Pricing

TermsOfService

PrivacyPolicy

Plans

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 1

Properties that don't map to a standard resource type

Overlay

Overlay

Source (apis.yml)

aid: stax
name: Stax
description: Stax (formerly Fattmerchant) is an Orlando, Florida payments technology company that sells subscription-priced
  payment processing to small and large merchants (Stax Pay), embedded payments and merchant onboarding to SaaS platforms
  and ISVs (Stax Connect), compliant credit-card surcharging (CardX by Stax), automated subscription billing (Stax Bill),
  and full-stack processing for partners and ISOs (Stax Processing). Its public REST API at apiprod.fattlabs.com covers charges,
  credits, refunds and voids, stored payment methods and tokenization, customers, invoices and invoice schedules, payment
  links, catalog items, terminals and card-present devices, merchant enrollment and underwriting, disputes, statements and
  deposit reporting, teams, users and API keys, and merchant- and partner-level webhooks. Stax.js handles browser tokenization;
  iOS and Android SDKs cover card-present and Tap to Pay. Stax Payments, Inc. is a registered ISO/MSP of Fifth Third Bank
  and Synovus Bank and a registered partner/ISO of Elavon, Inc.
url: https://raw.githubusercontent.com/api-evangelist/stax/refs/heads/main/apis.yml
x-type: company
x-source: harvest:secondary-market
x-tier: profiled
x-tier-reason: enrichment
accessModel:
  pricing: paid
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Paid
  confidence: high
  source:
  - plans
  - authentication
  - rate-limits
  - security
  - sandbox
  generated: '2026-09-03'
  method: derived
specificationVersion: '0.20'
created: '2026-08-29'
modified: '2026-09-16'
tags:
- Payments
- Payment Processing
- Merchant Services
- Embedded Payments
- ACH
- Invoicing
- Subscription Billing
- Surcharging
- Point-of-Sale
- Tokenization
- Financial-Services
- Fintech
- Card Present
- Merchant Onboarding
tags_raw:
- Payments
- Payment Processing
- Merchant Services
- Embedded Payments
- ACH
- Invoicing
- Subscription Billing
- Surcharging
- Point of Sale
- Tokenization
- Financial Services
- Fintech
- Card Present
- Merchant Onboarding
apis:
- aid: stax:stax-admin-api
  name: Stax Admin API
  description: The Admin API from Stax — 1 operation(s) for admin.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Admin
  properties:
  - type: OpenAPI
    url: openapi/stax-admin-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-charge-api
  name: Stax Charge API
  description: The Charge API from Stax — 1 operation(s) for charge.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Charge
  properties:
  - type: OpenAPI
    url: openapi/stax-charge-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-credit-api
  name: Stax Credit API
  description: The Credit API from Stax — 1 operation(s) for credit.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Credit
  properties:
  - type: OpenAPI
    url: openapi/stax-credit-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-customer-api
  name: Stax Customer API
  description: The Customer API from Stax — 3 operation(s) for customer.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Customers
  tags_raw:
  - Customer
  properties:
  - type: OpenAPI
    url: openapi/stax-customer-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-ephemeral-api
  name: Stax Ephemeral API
  description: The Ephemeral API from Stax — 1 operation(s) for ephemeral.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Ephemeral
  properties:
  - type: OpenAPI
    url: openapi/stax-ephemeral-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-file-api
  name: Stax File API
  description: The File API from Stax — 5 operation(s) for file.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - File
  properties:
  - type: OpenAPI
    url: openapi/stax-file-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-file-id-api
  name: Stax File{id} API
  description: The File{id} API from Stax — 1 operation(s) for file{id}.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags: []
  tags_raw:
  - File{id}
  properties:
  - type: OpenAPI
    url: openapi/stax-file-id-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-forgot-api
  name: Stax Forgot API
  description: The Forgot API from Stax — 1 operation(s) for forgot.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Forgot
  properties:
  - type: OpenAPI
    url: openapi/stax-forgot-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-invoice-api
  name: Stax Invoice API
  description: The Invoice API from Stax — 9 operation(s) for invoice.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Invoices
  tags_raw:
  - Invoice
  properties:
  - type: OpenAPI
    url: openapi/stax-invoice-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-item-api
  name: Stax Item API
  description: The Item API from Stax — 5 operation(s) for item.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Item
  properties:
  - type: OpenAPI
    url: openapi/stax-item-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-merchant-api
  name: Stax Merchant API
  description: The Merchant API from Stax — 7 operation(s) for merchant.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Merchants
  tags_raw:
  - Merchant
  properties:
  - type: OpenAPI
    url: openapi/stax-merchant-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-payment-method-api
  name: Stax Payment Method API
  description: The Payment Method API from Stax — 4 operation(s) for payment method.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Payment Method
  properties:
  - type: OpenAPI
    url: openapi/stax-payment-method-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-query-api
  name: Stax Query API
  description: The Query API from Stax — 14 operation(s) for query.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Query
  properties:
  - type: OpenAPI
    url: openapi/stax-query-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-reset-api
  name: Stax Reset API
  description: The Reset API from Stax — 1 operation(s) for reset.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Reset
  properties:
  - type: OpenAPI
    url: openapi/stax-reset-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-self-api
  name: Stax Self API
  description: The Self API from Stax — 4 operation(s) for self.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Self
  properties:
  - type: OpenAPI
    url: openapi/stax-self-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-surcharge-api
  name: Stax Surcharge API
  description: The Surcharge API from Stax — 1 operation(s) for surcharge.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Surcharge
  properties:
  - type: OpenAPI
    url: openapi/stax-surcharge-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-team-api
  name: Stax Team API
  description: The Team API from Stax — 8 operation(s) for team.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Team
  properties:
  - type: OpenAPI
    url: openapi/stax-team-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-terminal-api
  name: Stax Terminal API
  description: The Terminal API from Stax — 13 operation(s) for terminal.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Terminal
  properties:
  - type: OpenAPI
    url: openapi/stax-terminal-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-transaction-api
  name: Stax Transaction API
  description: The Transaction API from Stax — 11 operation(s) for transaction.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Transaction
  properties:
  - type: OpenAPI
    url: openapi/stax-transaction-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-underwriting-api
  name: Stax Underwriting API
  description: The Underwriting API from Stax — 5 operation(s) for underwriting.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Underwriting
  properties:
  - type: OpenAPI
    url: openapi/stax-underwriting-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-verify-api
  name: Stax Verify API
  description: The Verify API from Stax — 1 operation(s) for verify.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Verify
  properties:
  - type: OpenAPI
    url: openapi/stax-verify-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-webhook-api
  name: Stax Webhook API
  description: The Webhook API from Stax — 2 operation(s) for webhook.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Webhook
  properties:
  - type: OpenAPI
    url: openapi/stax-webhook-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
- aid: stax:stax-webhookadmin-api
  name: Stax Webhookadmin API
  description: The Webhookadmin API from Stax — 2 operation(s) for webhookadmin.
  humanURL: https://docs.staxpayments.com/reference/overview
  baseURL: https://apiprod.fattlabs.com
  tags:
  - Webhookadmin
  properties:
  - type: OpenAPI
    url: openapi/stax-webhookadmin-api-openapi.yml
  - type: Documentation
    url: https://docs.staxpayments.com/
  - type: APIReference
    url: https://docs.staxpayments.com/reference/overview
  - type: Examples
    url: examples/stax-api-examples.yml
  - type: DataModel
    url: data-model/stax-data-model.yml
  - type: ErrorCatalog
    url: errors/stax-problem-types.yml
  - type: Webhooks
    url: asyncapi/stax-webhooks.yml
  - type: AgenticAccess
    url: agentic-access/stax-agentic-access.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: AgenticAccess
  url: agentic-access/stax-agentic-access.yml
- type: Website
  url: https://staxpayments.com/
- type: DeveloperPortal
  url: https://docs.staxpayments.com/
- type: Documentation
  url: https://docs.staxpayments.com/
- type: APIReference
  url: https://docs.staxpayments.com/reference/overview
- type: GettingStarted
  url: https://docs.staxpayments.com/docs/getting-started
- type: Support
  url: https://support.fattmerchant.com/
- type: Blog
  url: https://staxpayments.com/blog/
- type: GitHubOrganization
  url: https://github.com/fattmerchantorg
- type: Pricing
  url: https://staxpayments.com/pricing/
- type: SignUp
  url: https://staxpayments.com/request-sandbox/
- type: Login
  url: https://app.staxpayments.com/
- type: TermsOfService
  url: https://staxpayments.com/terms-of-use/
- type: PrivacyPolicy
  url: https://staxpayments.com/privacy/
- type: StatusPage
  url: https://status.staxpayments.com/
- type: ChangeLog
  url: changelog/stax-changelog.yml
- type: Lifecycle
  url: lifecycle/stax-lifecycle.yml
- type: Authentication
  url: authentication/stax-authentication.yml
- type: Conventions
  url: conventions/stax-conventions.yml
- type: Idempotency
  url: conventions/stax-conventions.yml
- type: RateLimits
  url: rate-limits/stax-rate-limits.yml
- type: Plans
  url: plans/stax-plans-pricing.yml
- type: ErrorCatalog
  url: errors/stax-problem-types.yml
- type: DeclineCodes
  url: errors/stax-decline-codes.yml
- type: Webhooks
  url: asyncapi/stax-webhooks.yml
- type: MCPServer
  url: mcp/stax-mcp.yml
- type: ToolCrosswalk
  url: mcp/stax-tool-crosswalk.yml
- type: LLMsTxt
  url: llms/stax-llms.txt
- type: Packages
  url: packages/stax-packages.yml
- type: SDKs
  url: packages/stax-packages.yml
- type: Components
  url: components/stax-components.yml
- type: Sandbox
  url: sandbox/stax-sandbox.yml
- type: DataModel
  url: data-model/stax-data-model.yml
- type: Conformance
  url: conformance/stax-conformance.yml
- type: Compliance
  url: conformance/stax-conformance.yml
- type: TrustCenter
  url: security/stax-trust-center.yml
- type: SecurityTxt
  url: well-known/stax-security.txt
- type: VulnerabilityDisclosure
  url: security/stax-vulnerability-disclosure.yml
- type: Security
  url: security/stax-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/stax-domain-security.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Examples
  url: examples/stax-api-examples.yml
- type: Overlay
  url: overlays/stax-api-overlay.yaml
- type: OpenAPI
  url: openapi/_original/stax-api-openapi.json
image: https://staxpayments.com/wp-content/uploads/2024/04/stax-logo-full.png
x-enrichment:
  date: '2026-08-29'
  status: enriched
  artifacts_added: 33
  pass: local-v1

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