lab reports · orreryAbstractIIIIIIIVV

treadcore · check-in report CI-009

Who Saw the Gun That Sank the Boat

Check-in report CI-009. Paul Richeson, treadcore.org; Claude Code (Claude Opus 5.5) as the pair. 19 October 2026. Companion records: journal 0057; LAB-REPORT-BRAIN.md sections 31 and 32; CI-008.

Source: documentation/checkins/CI-009-2026-10-19-who-saw-the-gun.md, built by orrery's tools/report/collect.py.

Abstract

CI-008 explained its null result by sight: a boat sees a gun only at the gun's own range, too late to choose around it. It proposed pricing the guns the team had seen (backlog 32). This step measured that explanation before building anything. Over 16 seeds, the boat had seen its killer in the 10 s before in 128 of 164 landfall deaths (78%); a teammate alone had seen it once. The explanation is withdrawn, and backlog 32 closes with no part to build. Boats land under guns they can see. Backlog 33 proposes standing off a covered beach, by a weight whose default Paul sets.

Index terms: partial observability, measurement before design, correction.

I. Introduction

A. Intent

To read backlog 32's premise, as CI-008 planned, before building its part.

B. The prompt

yes 0. commit. push. continue backlog

(The same message as CI-008; this is its continuation.)

II. Decision Log

#CauseDecisionNot taken, and why
D1CI-008 D6: read firstSample each trial seat's sight at 1 Hz; class each landfall death's killerBuilding the remembered-gun price first
D2Cost1 Hz sampling under CENSUS_ACTS onlyEvery tick: 20 times the cost for a share bounded either way
D3F: the boat saw its killer in 78%CI-008's explanation withdrawn, marked in LR 31; backlog 32 closedBuilding 32 anyway: a teammate added a gun once in 164
D4F: boats land under guns they seeBacklog 33, standing off, as a weightChoosing its default: Paul's to give

III. Methods

In brain_census (fleet.rs), at each 1 Hz sample and for each living trial seat, w.observe(p).hostile_tanks() records (seat, owner) → tick. At a TankDestroyed of a trial seat whose last code was landfall and whose by is set, the killer counts as seen by the boat if (owner, by) is within 10 s, and by a teammate if any other trial seat's is. Null run, CENSUS_SEED0 0, 6, 11 with CENSUS_SEEDS 6, 5, 5; naval.map, 900 s, respawns 3, the fair census.

IV. Results

Seen byDeathsShare
both12878.0%
neither3521.3%
a teammate only10.6%
the boat only00

Null: 0.00 on every seed. Tests: brain 71 passed and 8 ignored; client 31; net 14; proto 3; sim 50.

V. Discussion

Two explanations in two steps were wrong: LR 29's equal shares (CI-007) and LR 31's sight (this report). Both were reasoned from the code rather than measured, and both were caught by the next step's read. They cost no code, because each read came before the part it would have justified. The working rule is to measure the premise of a backlog item before building it.

Next: Paul's default for landfall_wait; then backlog 33.