Plain Polish

Owners of the words: the service-designer agent for screens (apps/pwa/messages/) and the conversation-designer agent for the assistant (packages/content/src/scenarios/). Engineers add keys with a draft; the owner signs off the wording before merge, and the plain-language-editor agent reviews larger changes. The voice standard is docs/product/brand-voice.md. Plain language is part of accessibility (the accessibility skill) and a direct answer to "simpler" in the brief.

Writing rules (zasady prostego języka)

1. Short sentences. ≤ 15 words is the target, 20 the hard limit. One idea per sentence.
2. "Ty" form, active voice. "Złożysz wniosek tutaj", not "Wniosek może zostać złożony".
3. The verb comes first in buttons. "Zapłać 210 zł", "Zastrzeż dowód", "Pokaż szczegóły".
4. The answer first, then the details. "Twój dowód jest ważny do 05.12.2026. Nowy zamówisz tutaj."
5. Numbers and dates are concrete. "za 11 dni (29.10)", not "w najbliższym czasie".
6. No officialese, no legal citations in the UI. Put the source in a "Skąd to wiemy?" link.
7. Name things the way people do. "dowód", "meldunek", "OC", "800 plus", not legal names (the legal name may appear once, in brackets).
8. One action per screen in matters. Optional things are clearly optional.
9. No blame in errors. Say what happened, what to do, and that nothing was lost.
10. Gender-neutral where possible. Use the persona's gender when known ("Zgubiłaś/Zgubiłeś" from persona data, never "Zgubiłeś/aś").

Officialese → plain

Urzędowo	Prosto
Dokonaj zgłoszenia	Zgłoś
W celu złożenia wniosku należy…	Żeby złożyć wniosek, …
Uprzejmie informujemy, że…	(drop it)
Wnioskodawca	Ty
Organ właściwy	urząd gminy / wydział komunikacji (name it)
Zameldowanie na pobyt stały	meldunek (na stałe)
Uiszczenie opłaty	zapłata, zapłać
Niniejszym potwierdzam	Potwierdzam
W przypadku braku…	Jeśli nie masz…
Termin ważności upływa	Ważny do
Wystąpił błąd	Nie udało się … Spróbuj jeszcze raz.

Confirmation wording (before anything is "sent")

• Heading = the action and its object: "Zastrzeżesz dowód ABC PRO123".
• Rows = only the data that will be used, each with a plain label.
• One sentence on consequences and undo: "Możesz to cofnąć w aplikacji w ciągu 14 dni."
• Buttons: primary repeats the action ("Zastrzeż dowód"), secondary "Zmień" or "Anuluj".
• After the action: a past-tense heading ("Dowód zastrzeżony"), time, what happens next.
• Always end with the prototype reminder where it matters: "W prototypie nic nie zostało wysłane."

Message catalogue

• apps/pwa/messages/pl/<namespace>.json, one namespace per feature: common, home, documents, assistant, reminders, privacy, settings, matters.<matter>.
• Keys are semantic (documents.validUntil), never the text itself. Polish is the source; other locales mirror the keys.
• ICU MessageFormat. Polish plurals need one, few, many and other:

{
  "reminders.dueIn": "{days, plural, one {za # dzień} few {za # dni} many {za # dni} other {za # dnia}}"
}

• Format dates, money and numbers with Intl in pl-PL at the app edge (src/platform/i18n): 21.11.2026, 1 926,76 zł (non-breaking spaces). Components receive formatted strings.
• No text inside components or packages/ui. Scenario text for the assistant lives in packages/content (same rules).
• The i18n library is the scaffold's choice (the scaffold-app skill). It must support ICU plurals.

Secondary languages

• The app ships 8 languages: pl (source), en, uk, de, cs, sk, lt, be (docs/decisions/languages-2026-10-25.md). The list lives in @mobywatel/brand (LOCALES).
• Every new key goes into all 8 catalogues in the same change. apps/pwa/src/platform/i18n.test.ts fails on a missing key, an empty message or a changed ICU argument. A half-translated screen is worse than none.
• Plurals: write the categories each language needs (uk, be, cs, sk, lt have few/many; de, en only one/other).
• Keep the informal "you" in every language (ти, ты, du, ty, tu) and the same terms as the visible labels.
• Machine translation is allowed as a draft. Mark it in the PR, and have a native speaker check before submission.

Assistant tone

• Calm, warm and brief. 1–3 sentences per turn, then options (chips) or a card.
• Says what it will do before doing it. Never claims to have sent anything without a confirmation.
• Admits limits plainly: "Tego nie załatwię w aplikacji. Możesz to zrobić w urzędzie gminy."
• Never invents fees, deadlines or law. If the content package has no source, it says so (the ai-assistant skill).

Review checklist

Read it aloud. Would a 70-year-old understand it the first time? Can the button text stand alone? Is every number concrete and every date formatted? Is the persona's gender right? Does it work at 200% zoom without truncation?