Stamped

Stamped is a reviews, ratings, and loyalty platform for e-commerce brands on Shopify, BigCommerce, and custom/headless platforms. Its V3 API is organized into three domains: Merchant Data (customers, products, orders), Loyalty Operations (points adjustments, VIP tiers, reward redemption, activities, and program reporting), and Reviews. Authentication is a shop-scoped Private API Key sent in the stamped-api-key header. Surfaced as a portfolio company of GV and enriched by the API Evangelist pipeline from Stamped's public developer documentation at developers.stamped.io.

Stamped publishes 5 APIs on the APIs.io network, including Customer Actions API, Customers API, Orders API, and 2 more. Tagged areas include Company, Consumer, Reviews, Ratings, and Loyalty.

Stamped’s developer surface includes documentation, API reference, getting-started guide, support, authentication, and 14 more developer resources.

🌐 Visit website 📡 Source on GitHub

31.1/100 thin ▬ flat Agent 26/100 agent aware Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

2 APIs

Company Consumer Reviews Ratings Loyalty E-Commerce Customer Marketing Shopify

Kin Score

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

Composite quality — 31.1/100 · thin

Contract Quality 11.7 / 23

Developer Ergonomics 8.7 / 18

Access Clarity 0.0 / 18

Operational Transparency 0.9 / 12

Contract Governance 0.5 / 11

Discoverability 6.8 / 9

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 26/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 6 / 6

MCP Server 0 / 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 0 / 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

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.

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/stamped: 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 5

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

Stamped Customer Actions API

The Customer Actions API from Stamped — 6 operation(s) for customer actions.

Stamped Customers API

The Customers API from Stamped — 3 operation(s) for customers.

Stamped Orders API

The Orders API from Stamped — 3 operation(s) for orders.

Stamped Products API

The Products API from Stamped — 3 operation(s) for products.

Stamped Program Reporting API

The Program Reporting API from Stamped — 2 operation(s) for program reporting.

Open Collections 6

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

API Collection

OPEN COLLECTION

Loyalty Operations Customer Actions API

OPEN COLLECTION

Loyalty Operations Customer Actions Customers API

OPEN COLLECTION

Loyalty Operations Customer Actions Orders API

OPEN COLLECTION

Loyalty Operations Customer Actions Products API

OPEN COLLECTION

Loyalty Operations Customer Actions Program Reporting API

OPEN COLLECTION

Security Posture 2

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

Stamped Authentication

apiKey · 1 scheme

SECURITY

Stamped Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Agentic Access 1

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

Stamped Agentic Access

26 operations · 15 acting

AGENTIC

Resources

Get Started 2

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

LLMsTxt

LLMsTxt

AgenticAccess

AgenticAccess

X-MCPServerCandidate

X-MCPServerCandidate

AgentSkill

AgentSkill

Design & Contract 5

Pagination, idempotency, versioning, errors, and events

Conventions

ErrorCatalog

DataModel

Conformance

Lifecycle

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 2

Status, limits, changes, and where to get help

Support

Support

Deprecation

Deprecation

Company 1

The organization behind the API

Website

Website

Other 1

Properties that don't map to a standard resource type

Overlay

Overlay

Source (apis.yml)

aid: stamped
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: true
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source:
  - authentication
  - security
  generated: '2026-09-03'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/stamped.png
name: Stamped
description: 'Stamped is a reviews, ratings, and loyalty platform for e-commerce brands on Shopify, BigCommerce, and custom/headless
  platforms. Its V3 API is organized into three domains: Merchant Data (customers, products, orders), Loyalty Operations (points
  adjustments, VIP tiers, reward redemption, activities, and program reporting), and Reviews. Authentication is a shop-scoped
  Private API Key sent in the stamped-api-key header. Surfaced as a portfolio company of GV and enriched by the API Evangelist
  pipeline from Stamped''s public developer documentation at developers.stamped.io.'
url: https://raw.githubusercontent.com/api-evangelist/stamped/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- gv
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-21'
tags:
- Company
- Consumer
- Reviews
- Ratings
- Loyalty
- E-Commerce
- Customer Marketing
- Shopify
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
apis:
- aid: stamped:stamped-customer-actions-api
  name: Stamped Customer Actions API
  description: The Customer Actions API from Stamped — 6 operation(s) for customer actions.
  humanURL: https://developers.stamped.io/docs/merchant-apis
  baseURL: https://stamped.io/api/v3/merchant
  tags:
  - Customer Actions
  properties:
  - type: OpenAPI
    url: openapi/stamped-customer-actions-api-openapi.yml
- aid: stamped:stamped-customers-api
  name: Stamped Customers API
  description: The Customers API from Stamped — 3 operation(s) for customers.
  humanURL: https://developers.stamped.io/docs/merchant-apis
  baseURL: https://stamped.io/api/v3/merchant
  tags:
  - Customers
  properties:
  - type: OpenAPI
    url: openapi/stamped-customers-api-openapi.yml
- aid: stamped:stamped-orders-api
  name: Stamped Orders API
  description: The Orders API from Stamped — 3 operation(s) for orders.
  humanURL: https://developers.stamped.io/docs/merchant-apis
  baseURL: https://stamped.io/api/v3/merchant
  tags:
  - Order
  tags_raw:
  - Orders
  properties:
  - type: OpenAPI
    url: openapi/stamped-orders-api-openapi.yml
- aid: stamped:stamped-products-api
  name: Stamped Products API
  description: The Products API from Stamped — 3 operation(s) for products.
  humanURL: https://developers.stamped.io/docs/merchant-apis
  baseURL: https://stamped.io/api/v3/merchant
  tags:
  - Product
  tags_raw:
  - Products
  properties:
  - type: OpenAPI
    url: openapi/stamped-products-api-openapi.yml
- aid: stamped:stamped-program-reporting-api
  name: Stamped Program Reporting API
  description: The Program Reporting API from Stamped — 2 operation(s) for program reporting.
  humanURL: https://developers.stamped.io/docs/merchant-apis
  baseURL: https://stamped.io/api/v3/merchant
  tags:
  - Program Reporting
  properties:
  - type: OpenAPI
    url: openapi/stamped-program-reporting-api-openapi.yml
common:
- type: Overlay
  url: overlays/stamped-loyalty-operations-overlay.yaml
- type: DomainSecurity
  url: security/stamped-domain-security.yml
- type: Website
  url: https://stamped.io
- type: DeveloperPortal
  url: https://developers.stamped.io
- type: Documentation
  url: https://developers.stamped.io/docs/getting-started
- type: APIReference
  url: https://developers.stamped.io/reference/
- type: GettingStarted
  url: https://developers.stamped.io/docs/getting-started
- type: Support
  url: https://stampedsupport.zendesk.com/hc/en-us
- type: LLMsTxt
  url: llms/stamped-llms.txt
- type: Authentication
  url: authentication/stamped-authentication.yml
- type: AgenticAccess
  url: agentic-access/stamped-agentic-access.yml
- type: Conventions
  url: conventions/stamped-conventions.yml
- type: ErrorCatalog
  url: errors/stamped-problem-types.yml
- type: DataModel
  url: data-model/stamped-data-model.yml
- type: X-MCPServerCandidate
  url: mcp/stamped-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: Conformance
  url: conformance/stamped-conformance.yml
- type: Lifecycle
  url: lifecycle/stamped-lifecycle.yml
- type: Deprecation
  url: lifecycle/stamped-lifecycle.yml
- type: AgentSkill
  url: skills/_index.yml
x-enrichment:
  date: '2026-07-21'
  status: enriched
  artifacts_added: 18
  pass: local-v1

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