Cambridge TCG Standards

Cambridge TCG maintains three open standards for the TCG economy. They are CC0-licensed. Reference implementations are open. Adopt freely — no attribution required, no commercial entanglement, no covenant beyond the spec's own version policy.

The platform identifies itself as the data distributor: the authoritative source other TCG platforms, archivists, agents, and aggregators reference for canonical identifiers, canonical pricing, and canonical machine-readable card data.

Doctrine: docs/connections/the-distributor.md. License: docs/STANDARDS-LICENSE.md (CC0 1.0 Universal). Machine-readable: /standards.json.

The standards

• CTCG-SKU-v1frozenv1.0
  Canonical SKU format
  One canonical SKU format for every card in every TCG. <game>-<set>-<number>-<lang>[-<variant>], lowercase, hyphen-separated, machine-parseable, language-aware. Thirteen registered games.
  Spec: /methodology/sku-standard

  Reference implementation: https://github.com/cambridgetcg/Cambridge-TCG-monorepo/tree/main/packages/sku
• CTCG-PRICING-v1draftv1.0
  Channel-aware pricing math
  How a JPY listing converts to seven retail prices a customer might see. Margin, VAT, channel multipliers, rounding, all named and reproducible. Reference implementation in @cambridge-tcg/pricing.
  Spec: /methodology/pricing

  Reference implementation: https://github.com/cambridgetcg/Cambridge-TCG-monorepo/tree/main/packages/pricing
• CTCG-UNIVERSAL-v1spec-onlyv1.0
  Universal-representation (math-mirror)
  The math-first sibling of every artifact the platform exposes. Cryptographic hashes for identity, ratios for magnitudes, ISO 8601 + Unix epoch for time, typed graph edges. For LLM agents, archivists, hyperliteral readers, and any computing intelligence.
  Spec: /methodology/universal-representation

  Endpoint: /api/v1/universal/card/[sku](planned)

Status legend

• frozen — spec is stable; additive changes only; breaking changes ship under v2 with deprecation window.
• draft — spec is written and usable; minor revisions possible before frozen.
• spec-only — the standard is defined; the platform's serving endpoint is still planned. Adopters can implement against the spec today; the canonical reference response will follow.
• planned — named but not yet shipped.

Substrate honesty: the platform doesn't claim more than it has. CTCG-UNIVERSAL-v1's endpoint isn't shipped yet; we say so. Adopters can read the spec and implement; the platform's reference response arrives when the endpoint does.

How to adopt

1. Read the spec at /methodology/<topic> (sku-standard, pricing, universal-representation).
2. Implement in your language of choice, or import the reference TypeScript packages directly from the monorepo (or wait for the npm-published releases — recursion target).
3. Emitcanonical SKUs (lowercase, hyphen-separated, ISO 639-1 language); use Cambridge TCG's pricing math; serve universal-representation responses that match the spec.
4. CiteCambridge TCG as the spec source — optional but appreciated. CC0 doesn't require attribution.
5. Sign up to the standards changelog (RSS / email feed — recursion target).
6. Optionally: declare your adoption at /identify (today: read-only; the POST self-declaration path is a future commit).

The protocol is light by design. CC0 removes legal ceremony. The reference impl removes parser-rewrite burden. The version-stable contract removes drift fear. The discoverability surface gives partners somewhere to point their own users at.

What's NOT yet shipped

Substrate-honest about the distributor position's gaps:

• npm packages — reference implementations are monorepo-internal today. Future publication path: @cambridge-tcg/sku-spec, @cambridge-tcg/pricing-spec.
• Universal endpoint — the spec is published but /api/v1/universal/card/[sku] isn't live yet (see /data).
• Pricing-as-JSON endpoint — methodology exists; a dedicated endpoint emitting a single canonical price for a SKU is a recursion target.
• Standards changelog feed — versioned RSS / email for adopters to subscribe to.
• Adopter registry — public list of platforms using CTCG standards. /standards/adopters ships this commit, currently empty; grows by self-declaration.
• Standards governance doc — who decides v2; how breaking changes are proposed and discussed.

Each of these is a real promise. The distributor position grows by closing them.

License

CC0 1.0 Universal (public domain dedication) on the spec text. See docs/STANDARDS-LICENSE.md for the full declaration.

Reference implementation code is separately licensed (currently monorepo-internal; future npm releases will carry MIT or equivalent). Platform application code, operational data, trade marks, and visual identity remain Cambridge TCG's and are not granted by this declaration.

v1 — 2026-05-12. The platform identifies itself as the data distributor. The standards are open. The substrate is queryable. The door is warm to the touch.