# Core Concepts

## One-Line Positioning

**Core Concepts are the foundation for understanding Claude Code Workflow** — Three-layer abstraction of Commands, Skills, Prompts, Workflow session management, and team collaboration patterns.

---

## 3.1 Three-Layer Abstraction

Claude Code Workflow's command system is divided into three layers of abstraction:

### 3.1.1 Commands - Built-in Commands

**Commands are the atomic operations of Claude Code Workflow** — Predefined reusable commands that complete specific tasks.

| Category | Count | Description |
| --- | --- | --- |
| **Core Orchestration** | 2 | ccw, ccw-coordinator |
| **CLI Tools** | 2 | cli-init, codex-review |
| **Issue Workflow** | 8 | discover, plan, execute, queue, etc. |
| **Memory** | 2 | prepare, style-skill-memory |
| **Workflow Session** | 6 | start, resume, list, complete, etc. |
| **Workflow Analysis** | 10+ | analyze, brainstorm, debug, refactor, etc. |
| **Workflow UI Design** | 9 | generate, import-from-code, style-extract, etc. |

::: tip Tip
Commands are defined in the `.claude/commands/` directory. Each command is a Markdown file.
:::

### 3.1.2 Skills - Composite Skills

**Skills are combined encapsulations of Commands** — Reusable skills for specific scenarios, containing multiple steps and best practices.

| Skill | Function | Trigger |
| --- | --- | --- |
| **brainstorm** | Multi-perspective brainstorming | `/brainstorm` |
| **ccw-help** | CCW command help | `/ccw-help` |
| **command-generator** | Generate Claude commands | `/command-generator` |
| **issue-manage** | Issue management | `/issue-manage` |
| **memory-capture** | Memory compression and capture | `/memory-capture` |
| **memory-manage** | Memory updates | `/memory-manage` |
| **review-code** | Multi-dimensional code review | `/review-code` |
| **review-cycle** | Code review and fix cycle | `/review-cycle` |
| **skill-generator** | Generate Claude skills | `/skill-generator` |
| **skill-tuning** | Skill diagnosis and tuning | `/skill-tuning` |

::: tip Tip
Skills are defined in the `.claude/skills/` directory, containing SKILL.md specification files and reference documentation.
:::

### 3.1.3 Prompts - Codex Prompts

**Prompts are instruction templates for the Codex model** — Prompt templates optimized for the Codex (GPT) model.

| Prompt | Function |
| --- | --- |
| **prep-cycle** | Prep cycle prompt |
| **prep-plan** | Prep planning prompt |

::: tip Tip
Codex Prompts are defined in the `.codex/prompts/` directory, optimized specifically for the Codex model.
:::

---

## 3.2 Three-Layer Relationship

```mermaid
graph TB
    A[User Request] --> B[ccw Orchestrator<br/>Intent Analysis → Workflow Selection → Execution]
    B --> C[Command Atom]
    B --> D[Skill Composite]
    B --> E[Prompt Template]
    C --> F[AI Model Call]
    D --> F
    E --> F
```

### 3.2.1 Call Path

1. **User initiates request** → Enter command or describe requirements in VS Code
2. **ccw orchestration** → Intent analysis, select appropriate workflow
3. **Execute Command** → Execute atomic command operations
4. **Call Skill** → For complex logic, call composite skills
5. **Use Prompt** → For specific models, use optimized prompts
6. **AI model execution** → Call configured AI model
7. **Return result** → Format output to user

---

## 3.3 Workflow Session Management

### 3.3.1 Session Lifecycle

```mermaid
graph LR
    A[Start<br/>Launch] --> B[Resume<br/>Resume]
    B --> C[Execute<br/>Execute]
    C --> D[Complete<br/>Complete]
    A --> E[List<br/>List]
    D --> F[Solidify<br/>Solidify]
```

### 3.3.2 Session Commands

| Command | Function | Example |
| --- | --- | --- |
| **start** | Start new session | `/workflow:session:start` |
| **resume** | Resume existing session | `/workflow:session:resume <session-id>` |
| **list** | List all sessions | `/workflow:session:list` |
| **sync** | Sync session state | `/workflow:session:sync` |
| **complete** | Complete current session | `/workflow:session:complete` |
| **solidify** | Solidify session results | `/workflow:session:solidify` |

### 3.3.3 Session Directory Structure

```
.workflow/
├── .team/
│   └── TC-<project>-<date>/      # Session directory
│       ├── spec/                  # Session specifications
│       │   ├── discovery-context.json
│       │   └── requirements.md
│       ├── artifacts/             # Session artifacts
│       ├── wisdom/                # Session wisdom
│       │   ├── learnings.md
│       │   ├── decisions.md
│       │   ├── conventions.md
│       │   └── issues.md
│       └── .team-msg/             # Message bus
```

---

## 3.4 Team Collaboration Patterns

### 3.4.1 Role System

Claude Code Workflow supports 8 team workflows, each defining different roles:

| Workflow | Roles | Description |
| --- | --- | --- |
| **PlanEx** | planner, executor | Planning-execution separation |
| **IterDev** | developer, reviewer | Iterative development |
| **Lifecycle** | analyzer, developer, tester, reviewer | Lifecycle coverage |
| **Issue** | discoverer, planner, executor | Issue-driven |
| **Testing** | tester, developer | Test-driven |
| **QA** | qa, developer | Quality assurance |
| **Brainstorm** | facilitator, perspectives | Multi-perspective analysis |
| **UIDesign** | designer, developer | UI design generation |

### 3.4.2 Message Bus

Team members communicate via the message bus:

```mermaid
graph LR
    A[Planner] -->|plan_ready| B[Executor]
    B -->|task_complete| A
    A -->|plan_approved| B
```

### 3.4.3 Workflow Selection Guide

| Task Objective | Recommended Workflow | Command |
| --- | --- | --- |
| New feature development | PlanEx | `/workflow-plan` |
| Bug fix | Lifecycle | `/debug-with-file` |
| Code refactoring | IterDev | `/refactor-cycle` |
| Technical decision | Brainstorm | `/brainstorm-with-file` |
| UI development | UIDesign | `/workflow:ui-design` |
| Integration testing | Testing | `/integration-test-cycle` |
| Code review | QA | `/review-cycle` |
| Issue management | Issue | `/issue` series |

---

## 3.5 Core Concepts Overview

| Concept | Description | Location/Command |
| --- | --- | --- |
| **Command** | Atomic operation commands | `.claude/commands/` |
| **Skill** | Composite skill encapsulation | `.claude/skills/` |
| **Prompt** | Codex prompt templates | `.codex/prompts/` |
| **Workflow** | Team collaboration process | `/workflow:*` |
| **Session** | Session context management | `/workflow:session:*` |
| **Memory** | Cross-session knowledge persistence | `ccw memory` |
| **Spec** | Project specification constraints | `.workflow/specs/` |
| **CodexLens** | Semantic code indexing | `.codex-lens/` |
| **CCW** | CLI invocation framework | `ccw` directory |

---

## 3.6 Data Flow

```mermaid
graph TB
    A[User Request] --> B[CCW Orchestrator<br/>Intent Analysis]
    B --> C[Workflow Selection]
    B --> D[Command Execution]
    B --> E[AI Model Invocation]
    B --> F[Result Return]
    C --> C1[PlanEx]
    C --> C2[IterDev]
    C --> C3[Lifecycle]
    D --> D1[Built-in commands]
    D --> D2[Skill calls]
    E --> E1[Gemini]
    E --> E2[Qwen]
    E --> E3[Codex]
    E --> E4[Claude]
    F --> F1[File modification]
    F --> F2[Memory update]
    F --> F3[Dashboard update]
```

---

## Next Steps

- [Workflow Basics](ch04-workflow-basics.md) — Learn various workflow commands
- [Advanced Tips](ch05-advanced-tips.md) — CLI toolchain, multi-model collaboration
- [Best Practices](ch06-best-practices.md) — Team collaboration standards, code review process