---
id: CB-WP-0022
kind: product
title: "The design instrument: findings about the game, with their reproductions"
status: active
state_hub_workstream_id: "fda16340-0049-4acf-884b-a5cfdbde47c0"
---

# Purpose

```
structural tier  L   (named a high-leverage pass by the maintainer, and it
                      amends INTENT — clay-borg gains a stated aspect)
chaos            d8 = 6  → no override
declared tier    L
```

Declaration 5 of chaos window 2. Tier L: separate survey, **adversarial
review**, ADR, then spec, then code.

## The insight, in the maintainer's words

> *"We should consider ourselves testing the game and document
> inconsistencies to report them back to the ground-game repo, so that the
> game designer can improve the rules accordingly… We should have the
> rigorous game simulation engine and a meta scope to capture notes about
> game design flaws, questions, results and protocols about trial games…
> This will provide clay-borg an additional aspect as a valuable game
> design tool."*

**This is already happening and has no home.** In five passes the engine
has produced, as a by-product of being rigorous:

| finding | how it surfaced |
|---|---|
| ten underdetermined rules points (U1–U10) | formalizing the dataset into testable rules |
| SOLVE offered on a face-down Problem, always inert | a human dragging it three rounds running |
| GR-A13 "wasted SOLVE" on a claimed Problem | a scenario that had to pick a default |
| GR-E01 unreachable below 5 seats | arithmetic over the deal count |
| six provisional scenario defaults | scenarios that could not be written without deciding something |
| GR-E03 / GR-E04 never played to the end | nobody noticed for nineteen passes |

Every one was found by *building the simulator*, not by playing. That is
the thing worth naming: **a simulator rigorous enough to refuse ambiguity
is a design instrument, because it cannot proceed past a rule that does
not decide.**

And every one of them has been carried in prose, in six different places,
and one sat unread in an inbox for four days.

## The load-bearing rule this must have

The project's standing failure is *unexecuted verification*. A design
register that collects opinions would reproduce it in a new medium.

> **A design finding is not admissible without its reproduction.**

Concretely: a scenario that fails, an arithmetic check that prints the
contradiction, a recorded game the reader can replay, or a named test.
*"This feels unbalanced"* is a note, not a finding. **GR-E01 is admissible
because 4/6/9 against 5/7/9 is a computation anyone can rerun; the SOLVE
inertness is admissible because a recorded session shows three no-ops.**

This is what would make clay-borg a design tool rather than a suggestion
box, and it is the one part of this proposal that must not be traded away
for convenience.

## The judgment I want reviewed, not assumed

The maintainer asked whether this should extend to *"a meta about the
clay-borg engine evolution itself."*

**My answer is no, and it should be argued rather than accepted.** That
register already exists and is load-bearing: `evidence/CB-EV-*` records
what each pass found, `decisions/ADR-*` records what was decided and what
was rejected, `gates.toml` records what every control has caught and what
would retire it, and workplans record what was attempted. Nineteen passes
of engine evolution are already captured, with dates, costs and
falsifiers.

**Building a second register for the same subject would be ceremony**, and
this project has a standing rule that a gate must cash out. The asymmetry
is the point: engine evolution has a home and game design does not.

If the adversarial review disagrees, that is exactly the kind of thing
tier L exists to surface.

## Task: survey how this is done elsewhere, and what we already have

```task
id: CB-WP-0022-T01
status: done
priority: high
state_hub_task_id: "6b8663b8-4143-4361-ad9e-7df0c4f4a19d"
```

`research/CB-RES-0007-*.md`.

**Do not survey issue trackers.** The question is narrower and more
interesting: how do rigorous rule systems record *the ambiguity they
found*? Candidates worth a benchmark-to-beat:

- **Errata and rulings practice** in published games (Magic's
  comprehensive-rules + rulings split, Netrunner's NAPD card rulings) —
  what makes a ruling *findable* years later.
- **Formal-methods counterexample traces** — a model checker's output is
  precisely a reproduction attached to a claim, which is the shape wanted
  here.
- **Conformance-suite provisional behaviour** — how W3C/WHATWG mark
  "implementation-defined" and how a spec later absorbs it.
- **What this repo already has**: `provisional: true` scenarios,
  `§Underdetermined`, `gates.toml`'s `caught`/`retire_if` shape, and the
  hub message that went unread. **The register must reuse the provisional
  machinery rather than compete with it.**

Name, per dimension, the property to beat — findability, reproducibility,
and whether a ruling can *close* a finding mechanically.

**Done 2026-08-03.**
[CB-RES-0007](../research/CB-RES-0007-design-instrument.md), with a
runnable baseline (`tools/design-baseline.py`).

**The baseline is us, and it is measured**: 6 findings across **11 files**
with no index, **2 of 6 (33%) with a runnable reproduction**, and U1–U10
raised 2026-07-30, first *read* 2026-08-03 — **4 days**, 0 of 10 ruled.

**The uncomfortable number is stated up front rather than left for the
review to find: the reproduction rule would reject four of our six
existing findings.** The survey answers it — none of the four is
expensive to reproduce, so the 33% is evidence that nobody was ever asked
for one, not that the rule is unaffordable.

**Magic corrected an assumption this pass was about to build on.** I
expected a ruling to be the authoritative resolution. It is not: rulings
are *"reminder information with no actual weight or rules meaning"*, and
the authoritative fix folds into the **Oracle** card text. **A finding
closes when the source changes, not when an annotation is added** — so
the register must be a queue that empties, not an archive that grows.
That is now a constraint on T03's lifecycle.

Model checkers supplied the reproduction rule independently (a
counterexample trace *is* the finding), and W3C's *implementation-defined*
mark is the one piece of machinery we already have and must reuse rather
than duplicate.

## Task: adversarial review

```task
id: CB-WP-0022-T02
status: todo
priority: high
state_hub_task_id: "d2597895-fe2e-4f1e-a3db-a5fb8833434c"
```

Tier L requires it. Give the reviewer the survey **and** the §judgment
above, and require an attempt at:

- **that the engine-evolution register is redundant** — the strongest
  counter is that ADRs record *decisions* and evidence records *findings*,
  but nothing records *what we learned about building engines*, which is a
  third thing;
- **that "carries its reproduction" is affordable** — if half the real
  findings cannot be reproduced cheaply, the rule will be quietly dropped
  and the register becomes a suggestion box anyway. *(Since this task was
  written the answer has hardened: two findings reached ground-game on
  wrong premises, and ground-game has itself ruled that reproductions are
  required. The reviewer should now press the opposite way — whether the
  rule is **sufficient**, given both bad premises would have shipped a
  passing test alongside a wrong description.)*
- **that a register is needed at all**, rather than one more section in
  `GroundRules.md §Underdetermined`, which already exists and already
  works.

Record the trail in `history/`, unpolished.

## Task: decide

```task
id: CB-WP-0022-T03
status: todo
priority: high
state_hub_task_id: "a2e85810-e949-4ea0-81fc-36b912af326c"
```

`decisions/ADR-0012-*.md`. At minimum:

- whether clay-borg's **INTENT gains a stated aspect** as a design
  instrument, and in what words — this is the change with the longest
  half-life in the pass;
- the finding **taxonomy**, and it should be grounded in the six findings
  above rather than invented: *underdetermined* (rules do not say),
  *inconsistent* (rules disagree with each other or the data), *inert* (a
  rule that cannot fire), *degenerate* (fires, but collapses play),
  *unplayed* (implemented, never played);
- the **lifecycle** and who owns each state: raised → reported → ruled →
  applied, or withdrawn;
- whether a finding without a reproduction is **rejected** or **admitted
  as a note** — and if admitted, how it is prevented from aging into an
  apparent finding.

## Task: specify

```task
id: CB-WP-0022-T04
status: todo
priority: high
state_hub_task_id: "60ddfeab-81b1-45e4-9ec9-91cc8ea7fb72"
```

`specs/GameDesign.md`, with metrics, because a spec without them is prose.

Candidate measures, to be argued not adopted:

- **findings with a runnable reproduction** — target 100%, and the
  denominator includes withdrawn ones;
- **time from raised to reported** — the U-items took four days to be
  *read*; that is the number this exists to fix;
- **findings closed by a ruling** vs **findings still open**, with age.

**ground-game has ruled on what a finding must carry** (GROUND-WP-0004
T02, 2026-08-04), and it is stricter than this pass proposed. Adopt it:

> 1. Arithmetic findings must ship a **runnable reproduction** *and* a
>    **row-level deal table** listing Surface and each hidden priority
>    separately — **never only "sum of file" or "deal depth N"**.
> 2. ground-game rulings that depend on arithmetic **should cite** that
>    reproduction id or path, so a later reader can re-run it.

The second half is theirs to keep. The first is ours, and it is a direct
consequence of both premises we got wrong: *"12 in the file"* was a sum
without a deal table, and *"offered on a face-down Problem"* was a
condition named without checking which one actually fired.

**So the reproduction rule gains a shape requirement, not just an
existence one.** A finding that ships a passing test but describes the
wrong quantity is still a bad finding — which is exactly what happened
twice. The spec must say what a reproduction has to *show*, not only that
one exists.

Also specify the **trial protocol**, which is the part with no precedent
here: a trial game is a `--record`ed session plus an observation log, so
*"we played it and X happened"* is replayable rather than remembered. The
engine already records sessions as scenarios; a trial is that plus notes,
and it must cost almost nothing or it will not be done.

## Task: build it, and backfill what is already known

```task
id: CB-WP-0022-T05
status: todo
priority: high
state_hub_task_id: "469413ba-ed47-4840-a60e-ee7f95dc06ff"
```

The register, the tool, and then **the six findings above entered into
it** — backfilling is the test. A register that cannot express findings
the project already has is the wrong register, and discovering that after
designing it is the point of doing it in this order.

`make design` (or equivalent) must report: open findings by kind, those
without a reproduction, and those never reported to their owner.

## Task: report to ground-game, mechanically

```task
id: CB-WP-0022-T06
status: todo
priority: high
state_hub_task_id: "c6a659bd-c495-4754-9332-baadad51012a"
```

Generate the report and send it. **The message that sat unread for four
days is the baseline to beat**, and the failure was not the message — it
was that nothing pointed at it and nothing tracked whether it was
answered.

So the report must land somewhere that persists: a file in `ground-game`
under its own workplan, not only an inbox entry. GROUND-WP-0002 already
holds the ten U-items; this should extend it rather than duplicate it.

Include the two sharpened findings this pass has already produced:

- **GR-E01 vs GR-S01** — the deal count puts 4/6/9 points in play against
  thresholds of 5/7/9, so either the count or the thresholds are wrong and
  no dataset reconciles them;
- **SOLVE's legality** against a face-down Problem or an unmatchable suit.

## Task: evidence

```task
id: CB-WP-0022-T07
status: todo
priority: high
state_hub_task_id: "4fb77911-486d-4d9e-a53d-c4e486c74ce2"
```

`evidence/CB-EV-0021-*.md`. *(Was CB-EV-0020 when written; CB-WP-0023
shipped that number first — `evidence/CB-EV-0020-solve-legality.md` — so
this one moves rather than collides.)*

- **Whether backfilling changed the design** — if all six findings fit the
  first taxonomy, say so and be suspicious of it.
- **What tier L cost against what it caught**, since this is the second
  full-weight L pass and CB-WP-0012's deleted its own structural trigger.
- **The engine-evolution question**, as the review left it.
- **Quote CB-WP-0021's cost by re-running the instrument.**