diff --git a/README.md b/README.md
index f569b0a..1274e9c 100644
--- a/README.md
+++ b/README.md
@@ -28,12 +28,17 @@ npm run check     # проверка типов (svelte-check)
    Чем дороже карточка, тем сложнее вопрос.
 3. Ведущий открывает вопрос, затем «Показать ответ», и решает:
    - **Засчитать +N** — команде идут очки;
+   - **Засчитать частично +N/2** — для «почти правильного» ответа ведущий может
+     дать половину стоимости вопроса;
    - **Не засчитывать** — без очков, но вопрос закрыт.
    - Штрафов и минусов нет.
-4. Для творческих вопросов (type `creative`) кнопка мягче:
+4. У некоторых вопросов есть необязательная **подсказка** 💡. Ведущий может
+   показать её по желанию. Если подсказка показана — ответ засчитывается только
+   за половину стоимости: мягкая помощь без давления.
+5. Для творческих вопросов (type `creative`) кнопка мягче:
    «Засчитать творческий ответ +N».
-5. Сыгранный вопрос затемняется и больше не выбирается.
-6. Когда сыграны все вопросы — экран результата с мягкой финальной фразой.
+6. Сыгранный вопрос затемняется и больше не выбирается.
+7. Когда сыграны все вопросы — экран результата с мягкой финальной фразой.
 
 Прогресс сохраняется автоматически — после перезагрузки игра продолжится с того же места.
 
@@ -41,6 +46,11 @@ npm run check     # проверка типов (svelte-check)
 
 Архитектура задумана так, чтобы наборы добавлялись без правок UI.
 
+**Структура набора:** ровно **5 категорий**, в каждой ровно **5 вопросов** с
+номиналами **100 / 200 / 300 / 500 / 1000** (от простого к сложному). Вопросы
+бывают `strict` (однозначный ответ) и `creative` (творческий). У вопроса может
+быть необязательное поле `optionalHint` — подсказка для ведущего.
+
 1. Создайте файл `src/lib/question-sets/<name>.ts`:
 
    ```ts
@@ -57,14 +67,14 @@ npm run check     # проверка типов (svelte-check)
          title: 'Категория',
          questions: [
            { id: 'q1', points: 100, question: '...', answer: '...', type: 'strict' },
-           { id: 'q2', points: 200, question: '...', answer: '...', type: 'strict' },
+           { id: 'q2', points: 200, question: '...', answer: '...', optionalHint: '...', type: 'strict' },
            { id: 'q3', points: 300, question: '...', answer: '...', type: 'strict' },
            { id: 'q4', points: 500, question: '...', answer: '...', type: 'creative' },
            { id: 'q5', points: 1000, question: '...', answer: '...', type: 'strict' }
            // ровно 5 вопросов с очками 100/200/300/500/1000
          ]
        }
-       // …остальные категории
+       // …ещё 4 категории (всего 5)
      ]
    };
    ```
diff --git a/development/_reference/ai/README.md b/development/_reference/ai/README.md
index 0454cd2..ae79390 100644
--- a/development/_reference/ai/README.md
+++ b/development/_reference/ai/README.md
@@ -10,6 +10,7 @@ Shared references for Codex and other AI coding agents in this project.
 | Autonomous agent harness | [autonomous-agent-harness.md](autonomous-agent-harness.md) |
 | Worker loop command | [scripts/run-agent-loop.mjs](scripts/run-agent-loop.mjs) |
 | Pi worker wrapper | [scripts/run-pi-worker.mjs](scripts/run-pi-worker.mjs) |
+| Question authoring | [question-authoring.md](question-authoring.md) |
 
 Use `npm run agent:loop -- --task "<concrete task>"` when Codex delegates
 implementation to Pi. Codex remains the orchestrator, verifier, reviewer, and
diff --git a/development/_reference/ai/question-authoring.md b/development/_reference/ai/question-authoring.md
new file mode 100644
index 0000000..a194079
--- /dev/null
+++ b/development/_reference/ai/question-authoring.md
@@ -0,0 +1,173 @@
+# Question Authoring Guide (for AI agents)
+
+How to create or extend a question set for the calm family quiz **without
+touching code, state, or UI**. Question sets are pure data files.
+
+> You are a bounded worker. Read [AGENTS.md](../../../AGENTS.md) and
+> [autonomous-agent-harness.md](autonomous-agent-harness.md) first. This guide
+> covers **content data only**. Do not change UI components, the game store, the
+> types (beyond what content needs — usually nothing), or add backend / auth /
+> editor / multiplayer unless your task explicitly asks.
+
+## TL;DR workflow
+
+1. Create `src/lib/question-sets/<name>.ts` exporting a `QuestionSet`.
+2. Register it in `src/lib/question-sets/index.ts` (import + add to the
+   `questionSets` array).
+3. Run `npm run check` to confirm types compile.
+4. (Only if your task asks) smoke-test in the browser with `npm run dev`.
+
+The selector screen lists sets from `questionSets` automatically — no UI edit
+needed.
+
+## Hard structure rules (non-negotiable)
+
+Every set must match this shape **exactly**:
+
+- **Exactly 5 categories** per set (`set.categories.length === 5`).
+- **Exactly 5 questions** per category.
+- **Fixed point values per category, in order:** `100, 200, 300, 500, 1000`.
+- These values come from `POINT_VALUES` in `src/lib/types.ts`. Never invent
+  other numbers (no 400, no 750).
+
+## Exact data shape
+
+Mirror of `Question` / `Category` / `QuestionSet` in `src/lib/types.ts`:
+
+```ts
+import type { QuestionSet } from '$lib/types';
+
+export const mySet: QuestionSet = {
+  id: 'my-set',                  // globally unique, kebab-case, stable forever
+  title: 'Моя тема',
+  description: 'Короткое тёплое описание.',
+  ageRange: '6+ лет',
+  categories: [
+    {
+      id: 'cat-1',               // unique WITHIN this set, stable
+      title: 'Категория',
+      questions: [
+        { id: 'q1', points: 100,  question: '…', answer: '…', type: 'strict' },
+        { id: 'q2', points: 200,  question: '…', answer: '…', optionalHint: '…', type: 'strict' },
+        { id: 'q3', points: 300,  question: '…', answer: '…', type: 'strict' },
+        { id: 'q4', points: 500,  question: '…', answer: '…', type: 'creative' },
+        { id: 'q5', points: 1000, question: '…', answer: '…', type: 'strict' }
+      ]
+    }
+    // …4 more categories (5 total)
+  ]
+};
+```
+
+## Unique ids (stability matters)
+
+- `set.id` — unique across **all** sets (e.g. `animals`, `cozy`, `space`).
+  Lowercase kebab-case. It is persisted in `localStorage`, so never rename it
+  after release.
+- `category.id` — unique **within the set**. Stable. Used in the played-question
+  key `categoryId:questionId`.
+- `question.id` — unique **within the category** (typically `q1..q5`). Stable.
+
+Changing any id after release breaks saved progress for players mid-game. Treat
+ids as immutable once shipped.
+
+## Difficulty progression (100 → 1000)
+
+Within each category, questions run simple → hard. The number only labels it;
+the **wording** carries the difficulty:
+
+- **100** — obvious warm-up; most answer instantly.
+- **200** — easy; may need a second's thought.
+- **300** — solid mid-level.
+- **500** — needs real knowledge or reasoning.
+- **1000** — the hard capstone; satisfying to land.
+
+## Question type: `strict` vs `creative`
+
+From `QuestionType` in `src/lib/types.ts`:
+
+- `strict` — there is one correct answer. Host button reads «Засчитать».
+  Use for facts: «Какое животное…?», «Где живут белые медведи?».
+- `creative` — open-ended, many acceptable answers. Host button reads
+  «Засчитать творческий ответ» (softer framing, no "wrong" feeling). Use for
+  imagination prompts: «Придумай…», «Опиши…».
+
+A category of facts is mostly/entirely `strict`; a category of imagination is
+mostly/entirely `creative`. A set can mix freely. The example sets
+(`animals.ts`, `cozy.ts`) keep roughly one `creative` category per set for
+balance.
+
+## `optionalHint` — scaffold, don't reveal
+
+`optionalHint?: string` is an optional nudge the host can show on demand.
+
+- **Why it costs points:** showing a hint means the answer can then only be
+  awarded at **half** value (see Boundaries). So it's a fair, pressure-free
+  trade — omit it whenever no scaffold genuinely helps.
+- **Do** point at a category, sense, rhyme, or well-known association:
+  - «Его часто называют царём зверей.» (for «Лев»)
+  - «Мама у него — кобыла, а папа — жеребец.» (for «Жеребёнок»)
+- **Don't** restate or obviously give away the answer:
+  - ❌ «Это лев.»
+  - ❌ «Ответ начинается на букву „Л“.»
+- **For `creative` questions**, the hint can loosen imagination instead of
+  narrowing it («Чем нелепее и добрее — тем лучше.»).
+- Keep it to **one short sentence**. Omit the field entirely when no scaffold
+  helps — it is genuinely optional.
+
+## Tone: calm, warm, Russian, family-friendly
+
+All user-facing text (`title`, `description`, `question`, `answer`,
+`optionalHint`) is in **Russian** and must stay calm and family-safe:
+
+- Soft, friendly phrasing; no words implying timers, pressure, or rush.
+- No scary, crude, political, or adult content.
+- Friendly to kids and grandparents together; avoid slang that ages badly.
+- Match the cozy register of the existing sets (`animals.ts`, `cozy.ts`).
+
+When unsure, read the existing sets and mirror their voice. Aim for a warm
+bedtime-evening mood.
+
+## Register the set
+
+In `src/lib/question-sets/index.ts`:
+
+```ts
+import { mySet } from './my-set';
+export const questionSets = [animalsSet, cozySet, mySet];
+```
+
+Order in the array is the order on the selector screen — new sets usually go
+last.
+
+## Validation checklist (run before reporting done)
+
+- [ ] File is `src/lib/question-sets/<name>.ts`; its export is a `QuestionSet`.
+- [ ] `set.id` is unique across all sets and kebab-case.
+- [ ] Exactly 5 categories; each `category.id` unique within the set.
+- [ ] Exactly 5 questions per category; each `question.id` unique within its category.
+- [ ] Each category's points are exactly `100, 200, 300, 500, 1000` in order.
+- [ ] Every question has `type` of `strict` or `creative`.
+- [ ] `optionalHint` (if present) scaffolds without revealing the answer; ≤ 1 sentence.
+- [ ] All copy is Russian, calm, family-friendly; matches the existing sets' tone.
+- [ ] Set is imported and added to `questionSets` in `index.ts`.
+- [ ] `npm run check` passes (types + svelte-check).
+
+## Boundaries — do NOT (unless your task explicitly says so)
+
+- Add backend, database, auth, accounts, or multiplayer.
+- Add a question editor UI or any new component / route.
+- Edit the game store (`src/lib/stores/game.ts`) or the `GameState` shape.
+- Change scoring, hint, or partial-credit mechanics — they already exist and are
+  fixed by the UI/state contract:
+  - Full points: host «Засчитать +N».
+  - Half points: host «Засчитать частично +N/2» (shown only when the hint was
+    **not** revealed; `halfPoints = Math.round(points / 2)`).
+  - Hint revealed → the answer can only be awarded at half value, and the
+    partial-credit button is hidden.
+- Refactor `src/lib/types.ts` beyond what content needs (usually nothing).
+- Commit, push, deploy, or edit `AGENTS.md` and other files under
+  `development/_reference/ai/`.
+
+If a needed change falls outside these boundaries, stop and report it; do not
+expand scope on your own.