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+# WO56 — The SOTA vision: terminal definition and full task set
+
+Status: **VISION** (owner-directed 2026-10-20) — every task below gets
+its own WO before execution; negatives recorded with the same rigor as
+positives.
+
+## Purpose (the abstract statement)
+
+Script conversion is the problem of moving language across writing
+systems: transliteration (authority-decreed convention), vocalization
+(recovering hidden readings — Arabic harakat, Hebrew nikud), and
+grapheme-to-phoneme (script to sound). The world's conventions for
+these exist as prose tables in standards documents — unexecutable,
+untestable, and re-implemented differently by every consumer.
+
+Interscript's purpose, stated abstractly: **turn social conventions
+into computational objects with provable behavior.**
+
+1. **Formalization** — the ISC language is the specification layer:
+   declarative, executable transduction with context conditions,
+   priority, dependencies, and a neural escape hatch for the
+   underdetermined residue. ISC is to transliteration what BNF is to
+   parsing.
+2. **Verification** — one document denotes one function; every runtime
+   computes it (cross-runtime parity, frozen conformance vectors,
+   embedded tests). Reference-implementation plus differential testing
+   as the interoperability guarantee.
+3. **Learned completion** — where the authority table underdetermines
+   the answer (abjads without vowels, abugidas with incomplete
+   marking), the mapping is a relation, not a function; models resolve
+   it under the same proof regime (pinned artifacts, byte-exact
+   runtimes, declared metrics, license provenance).
+4. **Distribution** — maps and models as verifiable, addressable,
+   versioned artifacts: the reproducibility layer.
+5. **Science** — the formalism, the corpus, the technique doctrine, and
+   the benchmarks are publishable, citable contributions.
+
+Terminal state (all five planes green) is the goal; "SOTA everywhere"
+is plane B's row set.
+
+## Plane A — Formal (the deterministic core)
+
+| id | task | acceptance |
+|----|------|-----------|
+| A1 | Authority-completeness audit: enumerate the universe (UN 1968–2016, BGN/PCGN current, ALA-LC full language list, ISO 9/233/259/3609/7098/843/9984/9985, ICAO 9303, national systems: DIN, RTGS, Korean RR, HK/ROC…), diff vs the 293 in `maps/` | coverage matrix published; every gap encoded or cited out-of-scope with authority reference |
+| A2 | Invertibility study: per-system round-trip analysis (map∘reverse = id?), loss conditions (homophone mergers, digraph ambiguity); generate reverse maps where authorities provide them | invertibility ledger for all systems; reverse maps shipped for every losslessly invertible one |
+| A3 | Equivalence formalization: system-equivalence checker + minimal distinguishing test-corpus generator | tool in runtime + CI; justifies alias/dedup decisions mechanically |
+| A4 | IS-1 v2: denotational semantics section — boundary, parallel priority, maybe composition, funcall typing; empty the ambiguity list | every runtime behavior derivable from the spec; zero open rulings |
+| A5 | Conformance certification kit: vector generator from authority documents; levels L0 parse → L1 embedded tests → L2 frozen vectors → L3 full parity | a third party can self-certify; kit ships as a package |
+
+## Plane B — Learned (the underdetermined residue)
+
+### The two phenomena that define this plane
+
+**Vocalization is composition, not a sibling task.** Undiacritized text
+is an *underspecified input*: the skeleton is a relation over readings,
+and romanizing it by convention (what bibliographic systems do) is a
+different product from predicting the hidden layer. Vocalization
+upgrades the relation into a function; the map then fires — ISC's
+`funcall` is this composition, declared, not hidden. Decode policy
+(first-alternates) is the principled selection layer over licensed
+readings. Evaluation consequence: single-gold DER systematically
+undercounts legitimate ambiguity — track **valid-reading-rate** (any
+dictionary-licensed reading scores) alongside DER/WER; this is the
+principled answer to the multiref problem (WO01's scar).
+
+**Abugidas (Thai, Khmer) presuppose a reading.** The script is a
+positional syllabary: vowel signs attach around clusters, inherent
+vowels are inferred, tone is computed from consonant class × syllable
+type — and RTGS then drops tone while TTS needs it. The convention is
+deterministic *over an inferred layer*. Architecture doctrine:
+**lexicon-first** (dictionary hit-rate is the first-class metric),
+model fallback for novel tokens (names), rule composite for the
+convention. Track three target layers separately: RTGS (toneless), IPA
+(toneless), IPA+tone (TTS). CTC cannot carry this (WO-banked); ByT5
+is the fallback learner.
+
+Technique doctrine (banked verdicts): CTC cannot model
+phonotactics; RL is knowledge-limited at SFT convergence; LLM teachers
+hallucinate haraqat (never); oracle relabel pays when teacher arms
+disagree; distillation needs decorrelated teachers; greedy beats beam
+on byte students; ByT5 is the byte-level backbone.
+
+| id | task | target |
+|----|------|--------|
+| B1 | Encode the dispatch doctrine: (script class, ambiguity type, data regime) → recipe, as registry defaults; include the two structural rules (vocalization-as-composition; abugida lexicon-first) and the relation→function decode policy | new language gets a recommended recipe automatically |
+| B2 | Hebrew: close the data-supply asks (owner), plane large arm, learned-IPA v0 | ReNikud-protocol DER < 5 (int8 < 6) — beats published SOTA |
+| B3 | Arabic: r8 noisy-student chain, r6-morph feature injection, register closure; valid-reading-rate alongside DER (the ambiguity-aware metric) | SadeedDiac DER < 2.0; WikiNews WER < 8; VRR reported |
+| B4 | Urdu: commercial-license G2P data path (owner decision); diacritization push | diac CER < 3; G2P license cleared |
+| B5 | Persian: register expansion (poetry, colloquial), Arabic-loan vocalization probe | hold CER < 0.7 across registers |
+| B6 | Thai: lexicon-first (Royal Institute dictionary hit-rate as first-class metric), model fallback for novel tokens, RTGS rule composite; three layers tracked (RTGS / IPA / IPA+tone) | published PER < 2; lexicon hit-rate reported; tone accuracy for the TTS layer |
+| B7 | Khmer: Chuon Nath lexicon-conditioned learner (khmer-dict-spice) — the abugida lexicon-first doctrine | CER < 15 (from 27.4); hit-rate reported |
+| B8 | Contribution proof: first 3 community languages through the 2-YAML path | framework story validated by outsiders |
+| B9 | External-benchmark certification: every headline claim reconciled to an external leaderboard protocol package | no self-graded SOTA claims |
+
+## Plane C — Verification
+
+| id | task | acceptance |
+|----|------|-----------|
+| C1 | Model × runtime conformance matrix: every shipped model byte-exact in ruby/ts/py, CI-enforced | matrix green, sustained |
+| C2 | Metric-convention enforcement: every metric in a gate declares convention + anchor | gate rejects undeclared metrics |
+| C3 | Performance budgets in CI (decode latency, artifact size) | budgets enforced, regressions block |
+
+## Plane D — Distribution
+
+| id | task | acceptance |
+|----|------|-----------|
+| D1 | Python release (owner: PyPI publisher registration) | 0.2.x live; test-and-report, never nag |
+| D2 | IS-1/ISC as citable standard: versioned spec releases, site pages, citation block | spec vN tagged; citable |
+| D3 | Catalogue completeness on the site (maps + models + runtimes status) | every shipped object browsable |
+
+## Plane E — Science
+
+| id | task | acceptance |
+|----|------|-----------|
+| E1 | Paper 1: the ISC formalism + corpus + interoperability methodology | draft against LREC/COLING-class venue |
+| E2 | Paper 2: technique dispatch for underdetermined mappings (the doctrine + per-language results) | draft with the full results matrix |
+| E3 | Frozen benchmark artifacts: conformance suites + eval protocols as citable releases | artifact-evaluation-ready |
+
+## Laws (unchanged, enforced by validators not memory)
+
+PRs only, never commit main · versions/licenses/requirements are owner
+decisions · no LLM as label teacher, ever · corpora pinned (dates or
+versions, sha256) with PROVENANCE · UNVERIFIED/LicenseRef-* block
+publish; owner waivers are `license_review:` records · data channel =
+GitHub Releases only, never raw.githubusercontent · HF Jobs only
+(--detach, --timeout ≥ 4h, step checkpoints, ≤ 2 concurrent GPU apps)
+· single-row greedy decode contract unless the artifact carries a
+masked encoder · ByT5 ids are byte+3 with trailing EOS · never delete
+files you did not create · transcribe whole documents, every section ·
+no fabricated claims — every number re-derives from a frozen artifact.