# Bilingual documentation

English | [中文](README.zh.md)

This repo's documentation is read by people and agents both inside and outside the company, so the README and the docs tree are maintained in English and Simplified Chinese. This page defines the pairing contract, the enforcement gate, and the rollout policy; [translation-rules.md](translation-rules.md) defines how to translate; [terminology.md](terminology.md) is the terminology source of truth. The committed agent workflow lives in [.agents/skills/dsh-translate-docs](../../.agents/skills/dsh-translate-docs/SKILL.md).

## The pairing contract

- **Both languages carry equal authority.** A document may be authored and reviewed in either language first — a Chinese-first RFC is as legitimate as an English-first one — and the counterpart is translated from it. Neither file outranks the other; what binds them is that they must say the same thing.
- **A pair is three sibling files.** The English `foo.md`, the Chinese `foo.zh.md`, and a consistency record `foo.i18n.yaml`, all in the same directory. No locale directories, no separate translation repo, no interleaved bilingual files. Pairs merge whole: a PR never lands one language without the other two files.
- **The consistency record.** `foo.i18n.yaml` holds the full git blob hash of each side as of the last time the two were confirmed to say the same thing:

  ```yaml
  foo.md: 3f786850e387550fdab836ed7e6dc881de23001b
  foo.zh.md: 89e6c98d92887913cadf06b2adb97f26cde4849b
  ```

  Blob hashes, not commit hashes, so the record is computable for files edited in the same PR (`git hash-object foo.md`) and consistency is a pure content comparison. The recorded hash also recovers the exact last-confirmed text of either side (`git cat-file -p <hash>`), so an out-of-sync pair is updated by diffing the edited side against its last-confirmed state and patching the counterpart minimally — never by re-translating whole files. After bringing the pair back in line, `pnpm run verify-translation-pairing --write` re-records both hashes; that yaml diff is the reviewable act of confirming consistency.
- **Language switcher.** Both files link to each other immediately after their H1 heading: the English file carries `English | [中文](foo.zh.md)` and the Chinese file carries `[English](foo.md) | 中文`.
- **Structure mirrors the counterpart.** Heading depths and order, list kinds, ordered-list starts, list item counts, table row and column counts, link targets, and verbatim code blocks match one to one across the pair — see [translation-rules.md](translation-rules.md) for the full preservation rules. Existing Markdown gates apply to `.zh.md` files unchanged (`verify-md-wrap`, `verify-md-links`).

## The gate: verify-translation-pairing

`pnpm run verify-translation-pairing` (part of `doc-sync`, so CI and the pre-push hook run it) enforces the contract mechanically:

1. Every file listed as `required` in [scripts/translation-pairing.manifest.json](../../scripts/translation-pairing.manifest.json) has a complete pair.
2. Every pair that exists at all — required or not — is complete and consistent: all three files present, each side's current blob hash equals the recorded one (editing either side without re-confirming the pair goes red), both sides carry the language switcher, and the structural signatures match in order — heading depths, verbatim code blocks (info string and content), table row and column counts, list kinds, ordered-list starts, item counts, and every link target apart from the switcher.
3. Files listed as `excluded` have no `.zh.md` and no `.i18n.yaml` at all.
4. Every date-named document (`yyyy-mm-dd-*.md`) dated on or after the manifest's `requiredSince` cutoff has a complete pair — new date-named RFCs merge bilingual from birth.

`pnpm run verify-translation-pairing --list` prints the current pairing state of every document in scope — missing, out-of-sync, or ok — and is the work list for translation batches. It never fails; it reports.

The practical rule this gate creates: **when a PR edits either side of a paired document, the same PR updates the counterpart and re-records the pair** (run the [dsh-translate-docs](../../.agents/skills/dsh-translate-docs/SKILL.md) skill, then `--write`), exactly like the repo's existing doc-sync rule for code and READMEs. A PR that leaves a pair out of sync goes red in CI.

The gate's limit, stated plainly: **a green gate means the pair was confirmed consistent at these exact contents, not that the confirmation was sound.** It checks hashes and shape; it cannot judge whether the two sides actually say the same thing, or whether the wording is accurate, well-termed, and natural — that is the reviewer's half of the contract, per [translation-rules.md](translation-rules.md). A re-recorded pair with a sloppy counterpart passes the gate; it must not pass review.

## Scope, exclusions, and rollout

**Scope**: the root `README.md`, everything under `docs/**`, and everything under `python/**`. Package READMEs (`packages/**`) join the scope in a later batch.

**Excluded** (never paired, and the gate rejects a `.zh.md` or `.i18n.yaml` for them):

- `docs/cordis-catalog/`, `docs/tool-catalog/`, `docs/config-catalog.md`, `docs/persistence-catalog.md`, and `docs/module-graph.md` — generated files; their generators emit English only today, so a hand-written translation would go stale on every regeneration. The planned follow-up is to teach the generators to emit Chinese alongside English, at which point these leave the exclusion list.
- `docs/AGENTS.md` — agent instructions, maintained in English only like the root `AGENTS.md`.
- `docs/i18n/terminology.md` and [style-samples.md](style-samples.md) — both are bilingual by construction.
- [translation-prompt.md](translation-prompt.md) — the automated pipeline's prompt template; its body is machine-consumed verbatim, so a paired translation would change pipeline behavior.

**Rollout**: a date-named document (`yyyy-mm-dd-*.md`, i.e. an RFC) dated on or after the manifest's `requiredSince` cutoff must merge with its pair. Earlier dates are backlog, including files created on the cutoff's eve. An RFC filename records its first-proposed date, so backdating past the cutoff is a review-visible violation. The manifest's `required` list is the current enforcement frontier, not the goal of full coverage. Translation batches add paths to `required`, ratcheting the gate forward. Unlisted documents remain visible in `--list`, while every existing pair is governed by the full contract. Because later edits must update both sides, expand `required` only as fast as translation review can support.

## Division of labor

Counterparts here are produced by an agent running [dsh-translate-docs](../../.agents/skills/dsh-translate-docs/SKILL.md) and reviewed by a human — inference is cheap here, review attention is the scarce resource. The gate checks pair completeness, recorded hashes, switchers, and its documented structural signature. Review still owns translation quality, terminology, and structural requirements that the signature does not encode. The prompt contract is executable: [scripts/translation-prompt.ts](../../scripts/translation-prompt.ts) renders the canonical rules into either direction and strictly parses the three-field XML response, while `verify-translation-prompt` exercises both render directions, the checked-in example, and the CDATA split rule in `doc-sync`.
