# Linux147 — passage audits on the Core cave planner

**Result:** The L145 ripple-distance audit and L146 passage-interior air gate pass across all 16 seeds in both requested matrices. The two matrices each measured 5,171,796 capsule samples inside passage interiors with **zero solid samples**. Their no-passage controls detected solid in 48/48 passage interiors, and their masked-gap ripple controls passed 48/48 times. No generation code changed.

The only non-green result is seed 2's known interface 2–3 shell/seam failure. Vertical Shafts remains 15/16, matching L139. The Tunnel Network comparison is 15/16 against L135's earlier 16/16; seed 2 is already known to fail after the L139 shaft change. It is not a failure introduced by either new audit gate.

## Audit changes

- `StreamBenchmarkPipeline.h` now requires zero solid capsule samples inside each passage interior. It runs the same interior classifier over the passage-stripped field and requires positive solid detections for every passage.
- The ripple fitter keeps each valid wall sample's actual route distance instead of compressing distances across missing probes. Its synthetic 5 m masked-gap control measures a 0.0581 m sine ripple and rejects a smooth cubic at 0.0000 m.
- No Core planner, evaluator, Unreal `Source/`, or generation code changed. `git diff --check` passed.

## Per-seed verdicts

Tunnel Network compares with the L135 16/16 composed sweep; Vertical Shafts compares with the L139 15/16 sweep. `P` means pass and `F` means fail.

| Seed | Tunnel Network baseline → L147 | Vertical Shafts baseline → L147 | Verdict change |
|---:|:---:|:---:|---|
| 0 | P → P | P → P | None |
| 1 | P → P | P → P | None |
| 2 | P → F | F → F | Tunnel comparison: L135 predates the L139 shaft change. Current seed 2 has the existing interface 2–3 shell/seam failure; the new interior and ripple gates pass. Vertical Shafts remains the same known failure. |
| 3 | P → P | P → P | None |
| 4 | P → P | P → P | None |
| 5 | P → P | P → P | None |
| 6 | P → P | P → P | None |
| 7 | P → P | P → P | None |
| 8 | P → P | P → P | None |
| 9 | P → P | P → P | None |
| 10 | P → P | P → P | None |
| 11 | P → P | P → P | None |
| 12 | P → P | P → P | None |
| 13 | P → P | P → P | None |
| 14 | P → P | P → P | None |
| 15 | P → P | P → P | None |

There were no newly passing seeds and no verdict changes caused by the added gates. For seed 2, all three passages reported `interior_air=PASS`; its interface 2–3 shell had eight `wall_missing` samples at route stations 489.627–490.321 m. The samples were outside the passage interior. The first was at `(-21.678, -1.714, -888.614) m`, with composed and native density `+2.341949`, expected wall classification, and wall-shell margin `−0.297164 m`. The passage and seam summaries fail as they did in L139. No interior-solid root cause trace was needed because the measured interior-solid count is zero.

## Measurements and checks

- Clang 19 standalone build (`-O2`, `-ffp-contract=off`, four jobs) passed. L147 source stamp: `c6b8a100355e271ddc40eb5973569d2ff4e2ba8d9c628c72f8e0af2493f0609f`.
- Tunnel Network: seeds 0–15, one composed run per seed, 430.715 s summed process time (13.542–51.457 s per seed); 15/16 passed. Logs and resolved layouts are under `Saved/Linux/l147/seeds/tunnel-network/`.
- Vertical Shafts: seeds 0–15, one composed run per seed, 392.185 s summed process time (13.069–39.769 s per seed); 15/16 passed. Logs and resolved layouts are under `Saved/Linux/l147/seeds/vertical-shafts/`.
- Across each matrix: 5,171,796 passage-interior capsule samples, 0 solid; 48/48 no-passage controls detected interior solid; 48/48 masked-gap ripple controls passed. Passage walkability, ripple, and all other existing gates passed for seeds other than the known seed-2 shell/seam failure.
- Fast tier passed in 357.3 s: `Saved/Linux/l147/fast/fast-summary.json`. The first invocation stopped before running checks because the verifier's expected binary path was empty; it passed after using the completed L147 build there.
- Owner identity comparison against the HEAD-stamped L140 binary passed: all pipeline hash lines, plan hash `538ee11456eb0dab`, resolved-layout identity `resolved-layout-v3-fnv64:d310515572977ebf`, and resolved-layout SHA-256 `50a0342902b6b897c5746fd86fac559244151894155cab6db0822229bfb877e4` matched. Details: `Saved/Linux/l147/identity/summary.json`.
- `git diff --check` passed. No L80 timing, Unreal build, Windows build, or cross-compiler determinism run was requested or performed.

Runners: [`RunL147SeedSweep.py`](RunL147SeedSweep.py) and [`RunL147OwnerIdentity.py`](RunL147OwnerIdentity.py). No Unreal `Source/` files changed.

## Remaining risk

The seed-2 interface 2–3 shell/seam failure remains unresolved. It does not put solid samples inside the passage interior and is unchanged from the known L139 Vertical Shafts result. This round made no generation fix.