# CB-EV-0019 — import the edition CB-WP-0021 T04. Tier M (structural M — adds or refuses an external dependency and changes how a game is set up; chaos d8=7 → no override). Closed 2026-08-05, four days after the code landed. **Delivered:** [ADR-0011](../decisions/ADR-0011-vendor-the-edition.md), `editions/ground-darvo-r0/Problems.csv` with a digest, a ~150-line reader in `games/ground/src/edition.rs`, `tools/edition-check.py`, and the ruled deal — Surface ∪ hidden `1..=k`. --- ## 1. What the import cost, and the budget it was measured against **The declaration's constraint was measured against the wrong denominator, and the ADR corrected it.** CB-WP-0021 said a CSV crate costs 21,613 lines against AM-4a's **3,798** of headroom — *"5.7× over, settled by measurement rather than preference."* `setup` and `problem_priorities` are `#[cfg(feature = "scenarios")]`. **They are not in the shipped runtime**, so AM-4a never sees them. Against AM-4b's graph: | | lines | |---|---:| | AM-4b headroom | 19,742 | | `csv` marginal (`csv` + `csv-core`; `ryu`/`itoa`/`memchr` already present) | **17,651** | **It fits, with 2,091 to spare — and was refused anyway**, on proportion: 89% of everything the budget had left, to read 20 rows. What shipped is a hand-rolled reader we own. **That is the third premise this pass had to correct**, and the second where a real number was computed against a mis-chosen denominator. The pattern is now well enough attested to name: *this project's arithmetic errors are not in the arithmetic.* CB-WP-0022 T02 produced two more of the same shape four days later. Current dependency position, `make dep-weight`: ``` AM-4c shipped-runtime 7,976 own lines per 100k third-party (diagnostic) AM-4c dev-toolchain 1,729 own lines per 100k third-party (diagnostic) ``` ## 2. What broke — and the hash blast radius was predicted, not discovered The task asked which it was. **Predicted, and then measured to be almost nothing.** T01's brief said Problem values and suits enter `GroundState`, which is hashed (K7), so *"every recorded state hash changes"*, and required the blast radius be established **before writing code**. ADR-0011 §Decision 3 did exactly that: | | | |---|---:| | scenario files pinning a state hash | **0** | So the feared radius was ~0. Scenarios assert on state *blocks*, not hashes; `replay-test` re-executes bundles and restores them; AM-7's probe asserts per-segment hashes within a run rather than against recorded literals. **No hash was grandfathered and none recorded as "was"** — ADR-0011's words: *a recorded hash that outliving the content it describes is a lie with a timestamp.* Verified today: - `make replay-test` — **14/14 controls passed**, including *"the bundle still replays after every control restored it"*; - `make am7` — scaling **0.985 / 0.998 / 1.018** (worst/median/best of 9) against a 0.9 floor. Green, after T06 fixed the *measurement* rather than lowering the floor. **What did break** was the scenario corpus's data assumptions: six scenario files needed value/suit updates (`gr-a02-solve`, `gr-e03-common-problem`, `gr-e04-coalitions`, `gr-f02-no-gate`, `gr-p05-solve-legality`) because they encoded stand-in numbers. That is the expected cost of replacing invented data with real data, and every one was a data edit rather than a logic change. ## 3. Do the endings mean anything now? Yes — and the margin is one point This is the question the pass existed for. Played today, 2 players, all-bots: ``` OUTCOME total 4 / threshold 5 group failure personal: P1 2 P2 2 mastery 2 problems: [1] Repair 2 claimed by P2 [2] Clarify 2 [3] Boundary 2 claimed by P1 ``` **Three Problems worth 2 each — 6 available against a threshold of 5.** The bots claimed two of three, scored 4, and lost by one point. **This confirms T02's control by play.** That control said: *"at 2p that means a **full clear**, since 2+2+2 against 5 leaves no slack."* It is exactly right — at two seats, leaving any single Problem unclaimed loses the game. The endings are not merely reachable; they are **tight**, which is a far better answer than "reachable" and was not guaranteed by the ruling. **And it retires the finding this pass was built around.** GR-E01 was raised as *"unreachable below 5 seats"* on 4/6/9 against 5/7/9. The real deal is 6/9/12 against 5/7/9. `gr-e01-threshold-unreachable-2p` is now `gr-e01-threshold-reachable-2p`, non-provisional, and the finding was **formally withdrawn to ground-game on 2026-08-05** (CB-WP-0022 T06) — because it took an adversarial review, four days later, for anyone to notice that this pass had already falsified it. **That is the sharpest thing in this evidence file.** The work that disproved GR-E01 is *in this workplan*. The workplan that quoted GR-E01 as its founding example was written the next day. Nothing connected them until a separate agent ran `git log`. ## 4. Quoting CB-WP-0020's cost — the instrument refuses T04 asked for CB-WP-0020's cost by re-running the instrument. It cannot be supplied: ``` $ python3 tools/cb-cost.py --slug CB-WP-0020 --by-task ABORT — no transcripts found for CB-WP-0020 ``` **The instrument aborts rather than estimating, which is correct behaviour** and is why the number is absent instead of wrong. CB-WP-0020's transcripts are outside the retained window. What the instrument does report, run today: ``` main $ 548.03 output 2,125,069 tok $ 56.16 10.1% subagent tree $ 5.50 cache_read 750,152,134 tok $394.44 71.3% TOTAL $ 553.53 write_1h 9,233,711 tok $ 97.48 17.6% UNATTRIBUTED $230.34 41.6% CB-WP-0021-T01 $ 17.15 3.1% PROVISIONAL — this pass's own CB-WP-0021-T06 $ 14.31 2.6% PROVISIONAL — this pass's own ``` **The two CB-WP-0021 rows are provisional and must not be quoted as final.** They are this pass's own spend, measured while writing this file, so the number is still moving — `loop-lint`'s `own-cost` rule caught the first draft asserting them flat, which is the rule working. **41.6% unattributed is the number worth carrying forward**, not any per-task figure. A cost instrument that cannot say where two-fifths of the spend went is a partial instrument, and the retention window is why the chain of *"quote the previous pass's cost"* — a rule designed to keep costs comparable across passes — **breaks after roughly four passes.** That rule should either be bounded to what the window holds, or the window extended. It is not this pass's to decide; it is recorded here because this is the first pass where the chain actually snapped. ## 5. Chaos window 2 **Declaration 4 of 12.** Structural M, d8 = 7, no override. The roll is recorded per §Loop tiers even though it changed nothing. Window 2 standing: no override has yet changed an outcome. The retirement condition — *retire if an override changes nothing twice running* — has not been triggered, because there have been no overrides to evaluate. ## Open after this pass - **The cost chain is broken** (§4) and the rule that depends on it needs a bound. - The wrong-denominator pattern (§1) now has three instances and no control. `facts-check` catches copies that disagree; nothing catches a number computed correctly against the wrong base.