⚠ Reconciled at canonical schema v1.0.0. This narrative was authored against a bespoke minimal schema (Agent D, PR #1) that is now superseded. Any claim below that a construct is “UNREPRESENTABLE in schema v1.0.0” or “pending-v1.1” refers to that bespoke schema, not the canonical one — the canonical schema expresses these constructs. The executable truth for this domain is the canonical scene fixture conformance/case-studies/auction-family/auction-family.json, which validates + audits clean via node conformance/runner/run.mjs. See case-studies/README.md for the reconciled status table and schema/BACKLOG-v1.1.md for the real findings.

Case Study: Auction-Family Commerce

Adversarial test corpus — executable. This is the auction-family domain in the Commerce Model Formal Sufficiency Test. Two JSON fixtures live under conformance/case-studies/auction-family/ and validate against schema v1.0.0 with zero errors. Run it: node conformance/audit.mjs conformance/case-studies/auction-family.

Fixtures:

english-auction.json — ascending-bid auction, two bidders, loser cancelled
dutch-auction.json — descending-price, first-accept wins

The domain and the hard cases it stresses

Auction commerce is market-making commerce: the price is not set before the transaction begins — it is determined by competitive bidding. The hard problem for the model is representing a commitment whose counterparty and final price are both unknown at the moment the bidder acts.

The spec resolves this with three interlocking pieces:

Piece	What it models
`ValueState::under_auction`	The item cannot be reserved or sold while the auction runs — the auction process controls allocation
`CommitmentState::tendered`	A bidder’s open offer, carrying the bid amount, the closing time, and (when outbid) a `superseded_by` pointer to the winner
`AuctionProcess` auxiliary record	Coordinates all tendered commitments; declares the winner; holds the mechanism parameters

What this domain stresses:

The losing bidder must be cancelled forward, never deleted. State Monotonicity (I-2) means a tendered → cancelled transition is the only legal resolution for a losing bid. The commitment is preserved as an immutable record.
superseded_by is set before cancellation. When Bidder B outbids Bidder A, A’s tendered state gains superseded_by: "C-BID-B" in the source of the cancellation transition. This lets the model trace the exact chain of bids that led to the outcome.
The winning value path is deterministic: under_auction → reserved (physical_stock) → transferred. The value never becomes available again mid-auction; under_auction is a lock. The reserved state carries the winning commitment_id as the basis, making the chain I-1 verifiable.
Payment precedes physical delivery (partially_fulfilled bridge). The winner’s commitment follows the same accepted → partially_fulfilled → fulfilled path as a standard order. There is no auction-specific shortcut in the lifecycle.
AuctionMechanism is a closed set of four. The schema defines only english, dutch, sealed_bid, and vickrey. This case study covers english and dutch. sealed_bid and vickrey differ only in mechanism parameters; the commitment/value lifecycle is identical.

Fixture 1 — English Auction (`english-auction.json`)

This fixture mirrors the spec’s worked example in full.

Scenario: A vintage oil painting (circa 1960, artist Hassan El Glaoui) is listed by its owner through a Casablanca auction house. Reserve price: 8,000 MAD. Minimum increment: 500 MAD. Auction runs for six days.

Parties:

id	role
`party_seller_hassan`	painting owner, seller
`party_bidder_a`	first bidder — loses
`party_bidder_b`	second bidder — wins
`party_auction_house`	intermediary, coordinates close

Step-by-step flow

1. Seller lists painting
   Value(val_painting_casablanca).state: available → under_auction {
     auction_process_id: "AUC-ENG-001"
     current_high_commitment: null
     closes_at: "2026-06-11T18:00:00+00:00"
   }

2. Bidder A bids 10,000 MAD
   Commitment(C-BID-A): draft → tendered {
     offer_amount: "10000", offer_currency: "MAD"
     closes_at: "2026-06-11T18:00:00+00:00"
     superseded_by: null
   }
   AuctionProcess(AUC-ENG-001).current_high_commitment: "C-BID-A"

3. Bidder B outbids at 12,000 MAD
   Commitment(C-BID-B): draft → tendered { offer_amount: "12000", superseded_by: null }
   Commitment(C-BID-A).tendered.superseded_by: "C-BID-B"  ← set before cancellation
   AuctionProcess(AUC-ENG-001).current_high_commitment: "C-BID-B"

4. Auction closes (2026-06-11T18:00:00+00:00)
   Commitment(C-BID-B): tendered → accepted
   Commitment(C-BID-A): tendered → cancelled { by: "party_auction_house", reason: "Outbid" }
   Value(val_painting_casablanca).state: under_auction → reserved {
     commitment_id: "C-BID-B", basis: "physical_stock"
   }
   AuctionProcess(AUC-ENG-001).state: closed {
     winning_commitment: "C-BID-B"
     winning_price_str: "12000", winning_currency: "MAD"
     reason: "normal_close"
   }

5. Fulfillment (same as a standard order, two-step)
   Fulfillment(F-PAY-AUCTION-1): planned → in_progress → completed  (bank transfer 12,000 MAD)
   Commitment(C-BID-B): accepted → partially_fulfilled → fulfilled
   Fulfillment(F-DEL-AUCTION-1): planned → in_progress → completed  (in-person handover at auction house)
   Value(val_painting_casablanca).state: reserved → transferred { to: "party_bidder_b" }

Lifecycle as a transition table

Intent INT-BID-A:   active → abandoned
Intent INT-BID-B:   active → converted("C-BID-B")

Commitment C-BID-A (loser):  draft → tendered → cancelled
Commitment C-BID-B (winner): draft → tendered → accepted → partially_fulfilled → fulfilled
  Fulfillment F-PAY-AUCTION-1:  planned → in_progress → completed
  Fulfillment F-DEL-AUCTION-1:  planned → in_progress → completed

Fixture 2 — Dutch Auction (`dutch-auction.json`)

Scenario: Zust x Casablanca releases a limited-edition sneaker (50 units) via a Dutch auction on the Agora platform. Starting price: 3,000 MAD, decrementing by 100 MAD every 30 minutes. The first buyer to accept the current displayed price wins their unit immediately — the auction for that unit closes the instant the first-accept fires.

Parties:

id	role
`party_brand_zust`	seller and fulfiller
`party_buyer_youssef`	buyer — accepts at 1,500 MAD
`party_platform_agora`	Agora commerce OS, orchestrates the dutch clock

Mechanism parameters

"dutch": {
  "start_price_str": "3000",
  "start_currency": "MAD",
  "decrement_str": "100",
  "interval_seconds": 1800
}

Price at accept: 3,000 − (100 × 15 intervals) = 1,500 MAD at T+7.5 hours.

Step-by-step flow

1. Unit listed under Dutch auction
   Value(val_sneaker_limited).state: under_auction {
     auction_process_id: "AUC-DUTCH-001"
     current_high_commitment: null (Dutch: no bids until first-accept)
     closes_at: "2026-06-13T18:00:00+00:00"
   }

2. Youssef accepts at 1,500 MAD (T+7.5h after open)
   Commitment(C-DUTCH-Y): draft → tendered {
     offer_amount: "1500", offer_currency: "MAD"
     superseded_by: null
   }
   Platform immediately applies first-accept rule:
   Commitment(C-DUTCH-Y): tendered → accepted  (same timestamp)
   AuctionProcess(AUC-DUTCH-001).state: closed {
     winning_commitment: "C-DUTCH-Y"
     winning_price_str: "1500"
     reason: "normal_close"
   }

3. Fulfillment
   Fulfillment(F-PAY-DUTCH-1): planned → in_progress → completed  (card, 1,500 MAD)
   Commitment(C-DUTCH-Y): accepted → partially_fulfilled → fulfilled
   Fulfillment(F-DEL-DUTCH-1): planned → in_progress → completed  (Aramex, 7 days)
   Value(val_sneaker_limited).state: transferred { to: "party_buyer_youssef" }

Dutch vs. English: model-level difference

In a Dutch auction the tendered and accepted transitions fire at the same timestamp — the first-accept is simultaneously the bid and the acceptance. The superseded_by field stays null because there is only ever one tendered commitment per unit: the winner. There are no losers to cancel.

The value still traverses under_auction → reserved → transferred — the same path as the English auction — because the item is locked during the clock run and only released to the buyer on commitment acceptance.

Invariants exercised

Invariant	How the auction domain exercises it
I-1 Value Conservation	`value.under_auction.auction_process_id` resolves to a real `AuctionProcess`. `AuctionProcess.tendered_commitments` lists only commitment ids that exist in the fixture. `AuctionProcess.closed.winning_commitment` resolves to a real commitment. `value.reserved.commitment_id` resolves to the winner.
I-2 State Monotonicity	Losing bid: `draft → tendered → cancelled` (legal). Winning bid: `draft → tendered → accepted → partially_fulfilled → fulfilled` (legal). No backward transitions. The `superseded_by` pointer is set in the source state of the cancellation transition, not as a separate mutation.
I-3 Capacity Verification	Both the winning bidder and the seller have `verified_at` timestamps before the commitment reaches `accepted`.
I-4 Temporal Integrity	Every history entry’s `at` timestamp is ≥ the previous entry’s `at`. The English auction demonstrates multi-day non-decreasing timestamps; the Dutch auction demonstrates same-second tendered→accepted.
I-5 Identity Permanence	All ids across parties, values, intents, commitments, fulfillments, and auction processes are unique within each fixture.

Extensions relied upon

Extension	What it adds
AuctionProcess	The coordination record that holds mechanism parameters, the list of tendered commitments, and the closed state with the winning commitment reference.
Tendered commitment state	Allows a commitment to express an open offer whose counterparty acceptance is contingent on a mechanism (highest bid at close, first accept). Carries `offer_amount`, `offer_currency`, `closes_at`, `superseded_by`.
UnderAuction value state	Prevents a value from being reserved or sold while an auction is active. Carries `auction_process_id`, `current_high_commitment`, `current_high_offer_amount/currency`, `closes_at`.
English auction mechanism	`reserve_price_str`, `reserve_currency`, `min_increment_str` — ascending bids, highest bid at close wins.
Dutch auction mechanism	`start_price_str`, `start_currency`, `decrement_str`, `interval_seconds` — descending clock, first-accept wins immediately.

What the model cannot represent (scope note)

The schema’s AuctionMechanism is a closed set of four variants: english, dutch, sealed_bid, vickrey. The spec v0.3 prose describes a ScoredSelection variant for government procurement (where bids are evaluated on technical + price criteria, not price alone). That variant is not in schema v1.0.0 and is not exercised here — it belongs to a separate government-procurement domain case study.

Run it

node conformance/audit.mjs conformance/case-studies/auction-family
# ✓ conformance/case-studies/auction-family/dutch-auction.json
# ✓ conformance/case-studies/auction-family/english-auction.json
# auditCommerce: 2 passed, 0 failed, 0 warnings, 2 fixtures

Case Study: Auction-Family Commerce #

The domain and the hard cases it stresses #

Fixture 1 — English Auction (english-auction.json) #

Step-by-step flow #

Lifecycle as a transition table #

Fixture 2 — Dutch Auction (dutch-auction.json) #

Mechanism parameters #

Step-by-step flow #

Dutch vs. English: model-level difference #

Invariants exercised #

Extensions relied upon #

What the model cannot represent (scope note) #

Run it #

Case Study: Auction-Family Commerce

The domain and the hard cases it stresses

Fixture 1 — English Auction (`english-auction.json`)

Step-by-step flow

Lifecycle as a transition table

Fixture 2 — Dutch Auction (`dutch-auction.json`)

Mechanism parameters

Step-by-step flow

Dutch vs. English: model-level difference

Invariants exercised

Extensions relied upon

What the model cannot represent (scope note)

Run it