# Phase 3: Skills & Context — Subplan

## Goal

Deliver a skill system (general + personal) with CRUD, a personal context editor per user, and context assembly that layers personal context and skill prompts into AI conversations, with frontend management pages and a skill selector in chat.

## Prerequisites

- Phase 2 completed: chat CRUD, SSE streaming, Claude API integration, context assembly, admin context editor
- `context_files` table already exists (Phase 2 migration)
- `chats.skill_id` column already exists (nullable, Phase 2)

---

## Database Schema (Phase 3)

### `skills` table (new)

| Column | Type | Constraints |
|---|---|---|
| id | UUID | PK (inherited from Base) |
| user_id | UUID | FK -> users.id ON DELETE CASCADE, NULL = general skill |
| name | VARCHAR(100) | NOT NULL |
| description | TEXT | NULL |
| system_prompt | TEXT | NOT NULL |
| icon | VARCHAR(50) | NULL (Lucide icon name) |
| is_active | BOOLEAN | NOT NULL, default true |
| sort_order | INTEGER | NOT NULL, default 0 |
| created_at | TIMESTAMPTZ | inherited from Base |

Also: add FK constraint `chats.skill_id` -> `skills.id ON DELETE SET NULL`.

---

## Tasks

### A. Backend Model & Migration (Tasks 1–3)

- [x] **A1.** Create `backend/app/models/skill.py`. Add `skills` relationship on User model. Add `skill` relationship on Chat model.
- [x] **A2.** Update `backend/app/models/__init__.py`: import Skill.
- [x] **A3.** Create migration `003_create_skills_add_chat_skill_fk.py`.

### B. Backend Schemas (Task 4)

- [x] **B4.** Create `backend/app/schemas/skill.py`. Extend `CreateChatRequest`/`UpdateChatRequest` with optional `skill_id`.

### C. Backend Services (Tasks 5–7)

- [x] **C5.** Create `backend/app/services/skill_service.py`: CRUD for personal + general skills with access checks.
- [x] **C6.** Extend `context_service.py`: add `get_personal_context`, `upsert_personal_context`.
- [x] **C7.** Extend `ai_service.py` `assemble_context`: add personal context (step 2) + skill prompt (step 3).

### D. Backend API Endpoints (Tasks 8–11)

- [x] **D8.** Create `backend/app/api/v1/skills.py`: personal skills CRUD.
- [x] **D9.** Extend `backend/app/api/v1/admin.py`: admin skills CRUD under `/admin/skills/`.
- [x] **D10.** Create `backend/app/api/v1/users.py`: `GET/PUT /users/me/context`.
- [x] **D11.** Update router, chats endpoints (skill_id validation on create/update).

### E. Frontend API (Tasks 12–13)

- [x] **E12.** Create `frontend/src/api/skills.ts` + extend `admin.ts` with admin skill functions.
- [x] **E13.** Create `frontend/src/api/user-context.ts`.

### F. Frontend Skill Selector (Tasks 14–15)

- [x] **F14.** Create `frontend/src/components/chat/skill-selector.tsx`.
- [x] **F15.** Update chat creation + chat window to support skill_id.

### G. Frontend Admin Skills (Tasks 16–17)

- [x] **G16.** Create `frontend/src/components/admin/skill-editor.tsx` (reusable form).
- [x] **G17.** Create `frontend/src/pages/admin/skills.tsx`.

### H. Frontend Personal Skills & Context (Tasks 18–19)

- [x] **H18.** Create `frontend/src/pages/skills.tsx`.
- [x] **H19.** Create `frontend/src/pages/profile/context.tsx`.

### I. Routing, Sidebar, i18n (Tasks 20–22)

- [x] **I20.** Update routes: `/skills`, `/profile/context`, `/admin/skills`.
- [x] **I21.** Update sidebar: add Skills nav, admin skills link.
- [x] **I22.** Update en/ru translations.

### J. Backend Tests (Task 23)

- [x] **J23.** Create `backend/tests/test_skills.py`.

---

## Acceptance Criteria

1. Migration creates `skills` table and adds FK on `chats.skill_id`
2. Admin can CRUD general skills; users cannot
3. Users can CRUD own personal skills; isolated from other users
4. Users can read/write personal context via `/users/me/context`
5. Context assembly: primary context + personal context + skill prompt
6. Chat creation/update accepts `skill_id`, validates accessibility
7. Skill selector dropdown in chat creation and header
8. Admin skills page, personal skills page, personal context editor
9. All UI text in English and Russian
10. Backend tests pass

---

## Status

**COMPLETED**