Outpost

Outpost is a Merchant of Record and Tax of Record platform for cross-border commerce, letting retailers sell into new markets while Outpost takes on the legal and tax liability — local payments, VAT/GST/sales-tax registration, calculation and filing, proforma invoicing for B2B bank transfers, and hosted merchant onboarding. Its server-to-server REST APIs (Tax of Record, Merchant of Record, and Hosted Onboarding) use OAuth2 client-credentials and JWT bearer authentication so merchants keep their own checkout and payment service providers (Stripe, Adyen) while Outpost handles compliance across jurisdictions. Founded by ex-Revolut operator Will Mahon-Heap and backed by Ribbit Capital and Better Tomorrow Ventures.

Outpost publishes 3 APIs on the APIs.io network. Tagged areas include Company, Merchant of Record, Tax of Record, Cross-Border Commerce, and Payments.

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

Outpost’s developer surface includes documentation, API reference, engineering blog, support, authentication, sandbox, and 14 more developer resources.

🌐 Visit website 📡 Source on GitHub

37.5/100 thin ▬ flat Agent 26/100 agent aware saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessSelf serve

3 APIs

Company Merchant of RecordTax of RecordCross-Border Commerce Payments Tax Compliance E-Commerce VAT Fintech Invoicing Onboarding

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 37.5/100 · thin

Contract Quality 8.8 / 21

Developer Ergonomics 8.9 / 17

Access Clarity 3.6 / 17

Operational Transparency 0.9 / 11

Contract Governance 1.9 / 10

Discoverability 6.9 / 9

Regulatory Posture 5.9 / 15

Agent readiness — 26/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 9 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 6 / 6

Agent Skills 0 / 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 could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% 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/outpost: 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 3

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

Outpost Tax of Record API

REST API that automates tax registration, calculation, and filing while the merchant keeps their own checkout and PSP. Server-to-server, OAuth2 client-credentials. Covers tax ca...

Outpost Merchant of Record API

REST API to issue proforma invoices for B2B customers paying by bank transfer, receive settlement webhooks, and retrieve tax invoices for payments and refunds processed through ...

Outpost Hosted Onboarding (Partner) API

Partner REST API to onboard existing merchants onto Outpost services with a hosted onboarding UI and asynchronous review workflow. JWT bearer auth, /partner/api prefix, staging ...

Event Specifications 1

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

Outpost Merchant Of Record Webhooks

ASYNCAPI

Security Posture 2

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

Outpost Authentication

oauth2/http · 2 schemes

SECURITY

Outpost Domain Security

TLSv1.2 · DMARC

SECURITY

Resources

Get Started 2

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

Sandbox

Sandbox

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

X-MCPServerCandidate

X-MCPServerCandidate

LLMsTxt

LLMsTxt

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

Conventions

Idempotency

ErrorCatalog

Webhooks

Lifecycle

DataModel

Conformance

Scroll for all 7

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Operate 1

Status, limits, changes, and where to get help

Support

Support

Commercial 2

Pricing, plans, and the legal terms of use

TermsOfService

TermsOfService

PrivacyPolicy

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Source (apis.yml)

aid: outpost
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: false
  label: Hosted service · you call their endpoint
  confidence: medium
  source:
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  - url: https://outpostnow.com
    status: 301
    note: declared website redirects to https://outpost.ai/ — a different registrable domain (outpostnow.com -> outpost.ai),
      possible rename or acquisition (probed 2026-09-03, roadmap#169)
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/outpost.png
name: Outpost
description: Outpost is a Merchant of Record and Tax of Record platform for cross-border commerce, letting retailers sell
  into new markets while Outpost takes on the legal and tax liability — local payments, VAT/GST/sales-tax registration, calculation
  and filing, proforma invoicing for B2B bank transfers, and hosted merchant onboarding. Its server-to-server REST APIs (Tax
  of Record, Merchant of Record, and Hosted Onboarding) use OAuth2 client-credentials and JWT bearer authentication so merchants
  keep their own checkout and payment service providers (Stripe, Adyen) while Outpost handles compliance across jurisdictions.
  Founded by ex-Revolut operator Will Mahon-Heap and backed by Ribbit Capital and Better Tomorrow Ventures.
url: https://raw.githubusercontent.com/api-evangelist/outpost/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- ribbit-capital
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Merchant of Record
- Tax of Record
- Cross-Border Commerce
- Payments
- Tax Compliance
- E-Commerce
- VAT
- Fintech
- Invoicing
- Onboarding
apis:
- name: Outpost Tax of Record API
  description: REST API that automates tax registration, calculation, and filing while the merchant keeps their own checkout
    and PSP. Server-to-server, OAuth2 client-credentials. Covers tax calculations, tax transactions, refunds, transaction
    invoices, and product-catalogue import (including Brazil NFS-e).
  humanURL: https://outpostnow.com/docs/api/tax-of-record/
  baseURL: https://api.outpostanywhere.com
  tags:
  - Tax of Record
  - Tax Calculation
  - Compliance
  properties:
  - type: Documentation
    url: https://outpostnow.com/docs/api/tax-of-record/
  - type: APIReference
    url: https://outpostnow.com/docs/api/tax-of-record/
- name: Outpost Merchant of Record API
  description: REST API to issue proforma invoices for B2B customers paying by bank transfer, receive settlement webhooks,
    and retrieve tax invoices for payments and refunds processed through Outpost. Server-to-server, OAuth2 client-credentials.
  humanURL: https://outpostnow.com/docs/api/merchant-of-record/
  baseURL: https://api.outpostanywhere.com
  tags:
  - Merchant of Record
  - Invoicing
  - Webhook
  tags_raw:
  - Merchant of Record
  - Invoicing
  - Webhooks
  properties:
  - type: Documentation
    url: https://outpostnow.com/docs/api/merchant-of-record/
  - type: APIReference
    url: https://outpostnow.com/docs/api/merchant-of-record/
- name: Outpost Hosted Onboarding (Partner) API
  description: Partner REST API to onboard existing merchants onto Outpost services with a hosted onboarding UI and asynchronous
    review workflow. JWT bearer auth, /partner/api prefix, staging and production environments.
  humanURL: https://outpostnow.com/docs/api/hosted-onboarding/
  baseURL: https://partner.outpostanywhere.com
  tags:
  - Onboarding
  - Partner
  properties:
  - type: Documentation
    url: https://outpostnow.com/docs/api/hosted-onboarding/
  - type: APIReference
    url: https://outpostnow.com/docs/api/hosted-onboarding/
common:
- type: Website
  url: https://outpostnow.com
- type: DeveloperPortal
  url: https://outpostnow.com/docs/api/tax-of-record/
- type: Documentation
  url: https://outpostnow.com/docs/api/tax-of-record/
- type: APIReference
  url: https://outpostnow.com/docs/api/tax-of-record/
- type: Blog
  url: https://outpostnow.com/blog/
- type: Support
  url: https://outpostnow.com/faq/
- type: TermsOfService
  url: https://outpostnow.com/mor-terms/
- type: PrivacyPolicy
  url: https://outpostnow.com/privacy-policy/
- type: Authentication
  url: authentication/outpost-authentication.yml
- type: Conventions
  url: conventions/outpost-conventions.yml
- type: Idempotency
  url: conventions/outpost-conventions.yml
- type: ErrorCatalog
  url: errors/outpost-problem-types.yml
- type: Webhooks
  url: asyncapi/outpost-merchant-of-record-webhooks.yml
- type: Lifecycle
  url: lifecycle/outpost-lifecycle.yml
- type: Sandbox
  url: sandbox/outpost-sandbox.yml
- type: DataModel
  url: data-model/outpost-data-model.yml
- type: Conformance
  url: conformance/outpost-conformance.yml
- type: X-MCPServerCandidate
  url: mcp/outpost-mcp.yml
  note: 'Renamed from MCPServer 2026-09-03 (roadmap#247): the manifest self-describes as status: candidate — a tool list derived
    from the published API contracts, not an existing server. The scorer already read the manifest and reported mcp_server
    correctly; the MCPServer type was crediting the artifact-type surfaces with a server that does not exist.'
- type: LLMsTxt
  url: llms/outpost-llms.txt
- type: DomainSecurity
  url: security/outpost-domain-security.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
x-enrichment:
  date: '2026-07-20'
  status: enriched
  artifacts_added: 12
  pass: local-v1

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