Development

pnpm --filter @spelling-creator/mcp start   # run the stdio server directly
pnpm --filter @spelling-creator/mcp test    # doc-builder + auth + tool-surface + validation tests

Where things live

File	Responsibility
src/tools.js	Tool definitions and handlers, transport-agnostic.
src/doc.js	Builds the canonical editor document; throws on input it can't turn into one.
src/patch.js	Applies id-addressed edit operations to an existing document.
src/standards.js	The authoring standard's prose half — the rules that need judgement.
src/validate.js	The authoring standard's enforceable half. See Lesson validation.
src/api.js	The hub client (the same Worker endpoints the web app uses).
src/auth.js	Supabase token rotation.

test/validate.test.js is built around one lesson written exactly to the standard, which must produce no errors and no warnings; the other cases mutate that fixture a rule at a time. Keep it that way — a false positive blocks an author who did nothing wrong, so the clean-lesson case is the one that matters most.