6048c70bee
Reproducing my offset result, the Decoder reported the same discrimination over 3311 records against my 1781, with exactness 49.6% against my 92.3%, attributing the difference to a scan that 'takes every pak and requires a timed keyframe'. Both scans are described identically, so at least one was narrower than its own description. Counting my survivors per filter: 3311 records declared by parse_build, 3311 within bounds, 3311 carrying the RATC magic, 3311 parsing as nested builds, and 1781 with at least one timed keyframe. So 3311 is the count BEFORE the timed filter. The arithmetic closes it: 1643/1781 is 92.3% and 1643/3311 is 49.6%, their figure exactly. Same numerator. Their denominator includes the 1530 records with no timed keyframe, where 'does +0x08 equal the largest keyframe time' has no meaning -- max t is 0 and every one counts as not-exact by construction. So their stated filter is not applied, and 49.6% is not a weaker version of 92.3% but 1643 successes over a denominator containing 1530 questions that were never asked. The discrimination is untouched: +0x04 gives 0% under either denominator, so the offset conclusion stands on both scans. And my own number needed a qualifier it did not carry. 92.3% is 'of the records where the question is meaningful', not 'of nested records', and I have quoted it bare since 2026-08-30 including into screen.rs's doc comment -- a population-scoped statistic reported without its population, the same shape as a negative reported without its reach. Qualified in place. Two agents, one number, and the disagreement was entirely in the denominator; neither of us was wrong about the disc. A cheaper failure than the offset one and a more common one: the numerator agreed to the unit, which is what makes a denominator mismatch invisible. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01N7FiFFFwbvG2uxdcEh8HyF
Sylpheed
A clean-room reverse engineering and port project for Project Sylpheed: Arc of Deception (Xbox 360, 2007).
Three things live here, in one repository so that a change spanning them lands as one commit:
| The decoders | crates/sylpheed-formats — the disc's formats, read and verified disc-wide |
| The port | port/ — a Godot 4 project, plus crates/sylpheed-export which converts a disc into the open asset tree it reads |
| The corpus | docs/re/ — what has been reverse engineered, with its evidence, its retractions and its dead ends |
You need your own copy of the game. No game content is in this repository and none ever will be. The exporter reads the disc you supply.
The oracle is the real game
sylpheed-cliand the Explorer are tools for verifying our decoding. They are hypotheses under test and they have been wrong. When something must be checked against the truth, the truth is the game running in Xenia Canary, captured — not any renderer of ours.
This is stated first because getting it backwards is the most expensive mistake this project has made.
Layout
crates/
sylpheed-formats/ the decoders. Disc-wide verified; the corpus is its spec
sylpheed-cli/ headless tools -- render a screen, dump a table, probe audio
sylpheed-viewer/ the Explorer: a human's window onto the disc. STATIC data only
sylpheed-export/ disc -> the open, moddable asset tree
port/ the Godot 4 project. Reads open formats ONLY
authored/ decisions that are NOT on the disc, each with its reason
data/
base/ generated by the exporter. Gitignored, never hand-edited
mods/ drop-in overrides. Yours
docs/
re/ the corpus: findings, refutations, method traps
game/ how the game is navigated -- menus, modals, flight
port/ the port's mission, its handoff contract, modding rules
-- and RUNNING.md, which is how you actually start it
agents/ how the agent team works together
tools/ capture harnesses, probes, the share tool
exchange/ transient inter-agent files. NOT in git
docker/ the agent containers
Where to start
docs/re/INDEX.md— what is decodeddocs/re/REFUTED.md— what has been tested and dieddocs/re/METHOD.md— traps this project has already paid fordocs/game/navigation.md— how the game is navigateddocs/port/MODDING.md— why the asset tree looks the way it does
Xenia Canary is a separate repository: it is a fork tracking upstream, and it carries our instrumentation.
Conventions
Confidence is per claim, never per document: ✅ CONFIRMED · 🟡 PROBABLE ·
❔ HYPOTHESIS · ❌ REFUTED. A withdrawn result is kept with its reasoning
rather than deleted — that is why the numbers here can be trusted.