/multi-backend

description: Run a backend-focused multi-model workflow for APIs, algorithms, data, and business logic.

Backend - Backend-Focused Development

Backend-focused workflow (Research → Ideation → Plan → Execute → Optimize → Review), Codex-led.

> **Prerequisite:** Requires the external `ccg-workflow` runtime, which is **not** part of the base ECC install. Initialize it with `npx ccg-workflow` to provision `~/.claude/bin/codeagent-wrapper` and the `~/.claude/.ccg/prompts/*` role files this command depends on. Without that runtime, this command will not run correctly.

Usage

/backend <backend task description>

Context

• Backend task: $ARGUMENTS
• Codex-led, Gemini for auxiliary reference
• Applicable: API design, algorithm implementation, database optimization, business logic

Your Role

You are the **Backend Orchestrator**, coordinating multi-model collaboration for server-side tasks (Research → Ideation → Plan → Execute → Optimize → Review).

**Collaborative Models**:

• **Codex** – Backend logic, algorithms (**Backend authority, trustworthy**)
• **Gemini** – Frontend perspective (**Backend opinions for reference only**)
• **Claude (self)** – Orchestration, planning, execution, delivery

---

Multi-Model Call Specification

**Call Syntax**:

# New session call
Bash({
  command: "~/.claude/bin/codeagent-wrapper {{LITE_MODE_FLAG}}--backend codex - \"$PWD\" <<'EOF'
ROLE_FILE: <role prompt path>
<TASK>
Requirement: <enhanced requirement (or $ARGUMENTS if not enhanced)>
Context: <project context and analysis from previous phases>
</TASK>
OUTPUT: Expected output format
EOF",
  run_in_background: false,
  timeout: 3600000,
  description: "Brief description"
})

# Resume session call
Bash({
  command: "~/.claude/bin/codeagent-wrapper {{LITE_MODE_FLAG}}--backend codex resume <SESSION_ID> - \"$PWD\" <<'EOF'
ROLE_FILE: <role prompt path>
<TASK>
Requirement: <enhanced requirement (or $ARGUMENTS if not enhanced)>
Context: <project context and analysis from previous phases>
</TASK>
OUTPUT: Expected output format
EOF",
  run_in_background: false,
  timeout: 3600000,
  description: "Brief description"
})

**Role Prompts**:

| Phase | Codex | |-------|-------| | Analysis | `~/.claude/.ccg/prompts/codex/analyzer.md` | | Planning | `~/.claude/.ccg/prompts/codex/architect.md` | | Review | `~/.claude/.ccg/prompts/codex/reviewer.md` |

**Session Reuse**: Each call returns `SESSION_ID: xxx`, use `resume xxx` for subsequent phases. Save `CODEX_SESSION` in Phase 2, use `resume` in Phases 3 and 5.

---

Communication Guidelines

1. Start responses with mode label `[Mode: X]`, initial is `[Mode: Research]` 2. Follow strict sequence: `Research → Ideation → Plan → Execute → Optimize → Review` 3. Use `AskUserQuestion` tool for user interaction when needed (e.g., confirmation/selection/approval)

---

Core Workflow

Phase 0: Prompt Enhancement (Optional)

`[Mode: Prepare]` - If ace-tool MCP available, call `mcp__ace-tool__enhance_prompt`, **replace original $ARGUMENTS with enhanced result for subsequent Codex calls**. If unavailable, use `$ARGUMENTS` as-is.

Phase 1: Research

`[Mode: Research]` - Understand requirements and gather context

1. **Code Retrieval** (if ace-tool MCP available): Call `mcp__ace-tool__search_context` to retrieve existing APIs, data models, service architecture. If unavailable, use built-in tools: `Glob` for file discovery, `Grep` for symbol/API search, `Read` for context gathering, `Task` (Explore agent) for deeper exploration. 2. Requirement completeness score (0-10): >=7 continue, <7 stop and supplement

Phase 2: Ideation

`[Mode: Ideation]` - Codex-led analysis

**MUST call Codex** (follow call specification above):

• ROLE_FILE: `~/.claude/.ccg/prompts/codex/analyzer.md`
• Requirement: Enhanced requirement (or $ARGUMENTS if not enhanced)
• Context: Project context from Phase 1
• OUTPUT: Technical feasibility analysis, recommended solutions (at least 2), risk assessment

**Save SESSION_ID** (`CODEX_SESSION`) for subsequent phase reuse.

Output solutions (at least 2), wait for user selection.

Phase 3: Planning

`[Mode: Plan]` - Codex-led planning

**MUST call Codex** (use `resume <CODEX_SESSION>` to reuse session):

• ROLE_FILE: `~/.claude/.ccg/prompts/codex/architect.md`
• Requirement: User's selected solution
• Context: Analysis results from Phase 2
• OUTPUT: File structure, function/class design, dependency relationships

Claude synthesizes plan, save to `.claude/plan/task-name.md` after user approval.

Phase 4: Implementation

`[Mode: Execute]` - Code development

• Strictly follow approved plan
• Follow existing project code standards
• Ensure error handling, security, performance optimization

Phase 5: Optimization

`[Mode: Optimize]` - Codex-led review

**MUST call Codex** (follow call specification above):

• ROLE_FILE: `~/.claude/.ccg/prompts/codex/reviewer.md`
• Requirement: Review the following backend code changes
• Context: git diff or code content
• OUTPUT: Security, performance, error handling, API compliance issues list

Integrate review feedback, execute optimization after user confirmation.

Phase 6: Quality Review

`[Mode: Review]` - Final evaluation

• Check completion against plan
• Run tests to verify functionality
• Report issues and recommendations

---

Key Rules

1. **Codex backend opinions are trustworthy** 2. **Gemini backend opinions for reference only** 3. External models have **zero filesystem write access** 4. Claude handles all code writes and file operations