n8n/packages/modules/mcp/frontend/README.md

@n8n/frontend-module-mcp

Frontend feature module. Consumed from source by the editor-ui shell through src/app/modules.manifest.ts; there is no build step and no dist.

Read the full guide at packages/@n8n/module-cli/frontend-module-guide.md. It gives the descriptor contract, the registration points and the known problems. This README gives a summary only.

pnpm turbo typecheck --filter=@n8n/frontend-module-mcp
pnpm turbo lint --filter=@n8n/frontend-module-mcp
pnpm turbo lint:styles --filter=@n8n/frontend-module-mcp
pnpm turbo test --filter=@n8n/frontend-module-mcp

Go through turbo, not pnpm --filter <pkg> typecheck: this package is consumed from source, and on a cold tree its platform dependencies have not been built yet. Turbo builds them first; the bare pnpm form does not.

Import rules

• Depend on L0–L2 platform packages only. The full list is in "Imports and boundaries" in the guide. Never import another @n8n/frontend-module-*, and never import @/… from the shell.
• @n8n/stores, @n8n/composables, @n8n/frontend-constants and @n8n/utils are subpath-only — import @n8n/stores/settings.store, not @n8n/stores.
• The no-cross-module rule is currently a convention: the shared tsconfig base omits sibling modules from paths, which blocks an accidental import but not a deliberate one (declaring the dependency makes it typecheck clean). The CAT-3692 tracks the ESLint rule that will enforce it.

Adding UI

vite.config.ts already carries the three plugins a design-system consumer needs, so a .vue file compiles in tests without further setup:

• @vitejs/plugin-vue — single-file components.
• unplugin-icons — the ~icons/lucide/* virtual modules behind N8nIcon.
• vite-svg-loader — design-system's custom/*.svg icon components. Without it an .svg import is a data-URI string, which Vue renders as a tag name.

src/__tests__/design-system-icons.test.ts renders one icon of each kind, so a plugin dropped from vite.config.ts fails this package's own suite. Keep that test while the module renders any design-system component.

SCSS goes in a scoped <style lang="scss"> block, with tokens from design-system — stylelint.config.mjs holds this package to the same rules the shell uses. Route components must load lazily — see the note in src/mcp.module.ts.