c2d2c:ds-govern — converge + freeze

Project parameters

Resolve parameters from C2D2C.md at the repo root (fallback: .claude/c2d2c.md); if absent, offer to bootstrap one from the template at ../../templates/C2D2C.template.md (plugin root; standalone installs without that file fetch https://raw.githubusercontent.com/BIAsia/c2d2c/main/templates/C2D2C.template.md). This skill uses TOKEN_HOME, SPEC_HOME, GATE_HOME, LAW_HOME, DS_ROUTE, TOKEN_EXPORT, GATES.

Core mental model: governance = convergence + freezing. Convergence without freezing drifts back within months; freezing without cleanup leaves two systems that mislead everyone who comes later. One governance pass must complete all five moves: single source, full migration, gate, dead-code removal, written rule.

0. Decide to govern

Trigger signals: the third hand-written variant of the same style; reviews correcting the same class of mistake repeatedly; a restore job discovering "this value exists five ways in the codebase". Scope first: which dimension (radius/shadow/color/spacing/a component API), which directories, which areas are exempt (demos/marketing pages/vendored code, usually).

1. Full-repo census

• rg every current spelling of the dimension into a list: each form × occurrence count × representative file.
• Derive the "rungs actually in use" from the list. The ladder grows out of usage, not out of thin air.
• Separate the exceptions: legitimate special cases (future exemption areas) vs. drift (to migrate).

2. Write the spec (STOP: user review)

Write the system doc in SPEC_HOME, covering:

• The ladder/recipe: fixed token table (e.g. a px-value radius ladder, a three-tier shadow recipe) and when each rung applies.
• Single source: where values live (tokens) and where logic lives (single-source modules like field-shell.ts, tone.ts).
• The ban list: which spellings become illegal (raw literals, raw palette classes, inline beziers…).
• Exemptions: directory-level exemptions plus allowlist semantics (the allowlist is a frozen baseline, not a door: existing debt may sit in it; new code may not enter).

Get the user's sign-off before touching code.

3. Converge the implementation

• Tokens go into TOKEN_HOME (one value often registers in several places: CSS variable + theme alias + class ladder + design-side export; put the "adding a rung = N edits" list in the spec).
• Absorb component APIs: geometry/color become component-owned (driven by size/variant; matching classes stripped from caller className), ending caller overrides.
• For heavy coupling use restyle-in-place: when the behavior layer can't move (blocked by a lynchpin component), swap only the visual shell, leave behavior in place, and record the blocker.

4. Migrate every caller

• Migrate all call sites in one pass; no dual-track period. If volume forces batching, each batch must be internally complete (that batch's components, callers, and tests move together).
• Anything the new API can't express flows back into step 2 as a spec fix, never as a caller-side loophole.

5. Freeze with a gate

• Write check:<system> into GATE_HOME: scan for banned spellings, skip exempt areas, match the allowlist exactly (file + pattern), fail everything else with a fix hint in the error message ("use X instead").
• Wire it into the CI aggregate so local GATES runs it too.
• The allowlist holds existing debt only: baseline what can't migrate today, then only ever shrink it.

6. Remove the dead code

• Delete old tokens, old classes, old components, barrel exports, types, i18n keys, unreferenced styles. Delete completely; keep nothing "just in case".
• Run GATES to confirm nothing dangles.

7. Write it back

• Add/update a rule in LAW_HOME: one-sentence rule + pointer to the spec + gate name, so future agents get it right without reading the spec.
• Create/update the DS_ROUTE preview page for the new ladder (token visualization + component state matrix).
• Run TOKEN_EXPORT to sync the token changes to the design side (the token flow described in c2d2c:c2d).

Reporting rhythm

• Steps 1-2 merge into one message: census findings + spec draft (STOP).
• After steps 3-7, close out: migration volume, gate list, deletion list, rules diff, MR link.