CardSpring

CardSpring was a card-linked offers and payments platform that provided an API for building card-linked applications, letting developers connect merchant point-of-sale systems and consumer payment cards to deliver digital coupons, loyalty rewards, and receipt-level offers. It was surfaced as a portfolio company of Accel and DCVC and added to the API Evangelist network as a stub for enrichment. The company was acquired by Twitter in 2014 and subsequently wound down; as of this pass every path on cardspring.com (including the old /help/developer_faq.html) 307-redirects to an Afternic "cardspring.com is for sale" domain-sale lander, developer.cardspring.com fails TLS with no matching certificate, and no first-party CardSpring packages remain on npm or RubyGems. There is no live developer portal, documentation, API, or OpenAPI surface to enrich. Sector: payments.

CardSpring is profiled on the APIs.io network. Tagged areas include Company, Payments, Card Linking, Offers, and Loyalty.

🌐 Visit website 📡 Source on GitHub

0.1/100 minimal ▬ flat Agent 0/100 human only Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

0 APIs

Company Payments Card Linking Offers Loyalty Commerce Defunct

Kin Score

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

Composite quality — 0.1/100 · minimal

Contract Quality 0.0 / 21

Developer Ergonomics 0.0 / 17

Access Clarity 0.0 / 17

Operational Transparency 0.0 / 11

Contract Governance 0.0 / 10

Discoverability 4.3 / 9

Regulatory Posture 0.0 / 15

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 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/cardspring: 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 →

Resources

Company 1

The organization behind the API

Website

Website

Source (apis.yml)

aid: cardspring
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - none
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/cardspring.png
name: CardSpring
description: 'CardSpring was a card-linked offers and payments platform that provided an API for building card-linked applications,
  letting developers connect merchant point-of-sale systems and consumer payment cards to deliver digital coupons, loyalty
  rewards, and receipt-level offers. It was surfaced as a portfolio company of Accel and DCVC and added to the API Evangelist
  network as a stub for enrichment. The company was acquired by Twitter in 2014 and subsequently wound down; as of this pass
  every path on cardspring.com (including the old /help/developer_faq.html) 307-redirects to an Afternic "cardspring.com is
  for sale" domain-sale lander, developer.cardspring.com fails TLS with no matching certificate, and no first-party CardSpring
  packages remain on npm or RubyGems. There is no live developer portal, documentation, API, or OpenAPI surface to enrich.
  Sector: payments.'
url: https://raw.githubusercontent.com/api-evangelist/cardspring/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- accel
- dcvc
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Payments
- Card Linking
- Offers
- Loyalty
- Commerce
- Defunct
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Website
  url: http://cardspring.com/
x-enrichment:
  date: '2026-07-20'
  status: nochange
  artifacts_added: 0
  pass: local-v1

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