fix(commands): make ace-tool MCP optional in multi-* commands with built-in fallbacks

The multi-* commands (multi-plan, multi-execute, multi-workflow, multi-backend,
multi-frontend) previously required ace-tool MCP (Augment Code) which is a paid
service. This change makes ace-tool completely optional by:

- Changing "MUST call" to "If ace-tool MCP is available" for enhance_prompt
- Changing mandatory search_context calls to optional with fallback procedures
- Adding detailed fallback instructions using Claude Code built-in tools
  (Glob, Grep, Read, Task/Explore agent) when ace-tool is unavailable
- Updating all translations (ja-JP, zh-CN) to match

This ensures multi-* commands work out of the box without ace-tool MCP configured.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

commands/multi-backend.md

@@ -85,13 +85,13 @@ EOF",
 
 ### 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**
+`[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
+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

commands/multi-execute.md

@@ -136,7 +136,7 @@ TaskOutput({ task_id: "<task_id>", block: true, timeout: 600000 })
 
 `[Mode: Retrieval]`
 
-**Must use MCP tool for quick context retrieval, do NOT manually read files one by one**
+**If ace-tool MCP is available**, use it for quick context retrieval:
 
 Based on "Key Files" list in plan, call `mcp__ace-tool__search_context`:
 
@@ -151,7 +151,12 @@ mcp__ace-tool__search_context({
 - Extract target paths from plan's "Key Files" table
 - Build semantic query covering: entry files, dependency modules, related type definitions
 - If results insufficient, add 1-2 recursive retrievals
-- **NEVER** use Bash + find/ls to manually explore project structure
+
+**If ace-tool MCP is NOT available**, use Claude Code built-in tools as fallback:
+1. **Glob**: Find target files from plan's "Key Files" table (e.g., `Glob("src/components/**/*.tsx")`)
+2. **Grep**: Search for key symbols, function names, type definitions across the codebase
+3. **Read**: Read the discovered files to gather complete context
+4. **Task (Explore agent)**: For broader exploration, use `Task` with `subagent_type: "Explore"`
 
 **After Retrieval**:
 - Organize retrieved code snippets

commands/multi-frontend.md

@@ -85,13 +85,13 @@ EOF",
 
 ### 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 Gemini calls**
+`[Mode: Prepare]` - If ace-tool MCP available, call `mcp__ace-tool__enhance_prompt`, **replace original $ARGUMENTS with enhanced result for subsequent Gemini calls**. If unavailable, use `$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 components, styles, design system
+1. **Code Retrieval** (if ace-tool MCP available): Call `mcp__ace-tool__search_context` to retrieve existing components, styles, design system. If unavailable, use built-in tools: `Glob` for file discovery, `Grep` for component/style 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

commands/multi-plan.md

@@ -71,7 +71,7 @@ TaskOutput({ task_id: "<task_id>", block: true, timeout: 600000 })
 
 #### 1.1 Prompt Enhancement (MUST execute first)
 
-**MUST call `mcp__ace-tool__enhance_prompt` tool**:
+**If ace-tool MCP is available**, call `mcp__ace-tool__enhance_prompt` tool:
 
 ```
 mcp__ace-tool__enhance_prompt({
@@ -83,9 +83,11 @@ mcp__ace-tool__enhance_prompt({
 
 Wait for enhanced prompt, **replace original $ARGUMENTS with enhanced result** for all subsequent phases.
 
+**If ace-tool MCP is NOT available**: Skip this step and use the original `$ARGUMENTS` as-is for all subsequent phases.
+
 #### 1.2 Context Retrieval
 
-**Call `mcp__ace-tool__search_context` tool**:
+**If ace-tool MCP is available**, call `mcp__ace-tool__search_context` tool:
 
 ```
 mcp__ace-tool__search_context({
@@ -96,7 +98,12 @@ mcp__ace-tool__search_context({
 
 - Build semantic query using natural language (Where/What/How)
 - **NEVER answer based on assumptions**
-- If MCP unavailable: fallback to Glob + Grep for file discovery and key symbol location
+
+**If ace-tool MCP is NOT available**, use Claude Code built-in tools as fallback:
+1. **Glob**: Find relevant files by pattern (e.g., `Glob("**/*.ts")`, `Glob("src/**/*.py")`)
+2. **Grep**: Search for key symbols, function names, class definitions (e.g., `Grep("className|functionName")`)
+3. **Read**: Read the discovered files to gather complete context
+4. **Task (Explore agent)**: For deeper exploration, use `Task` with `subagent_type: "Explore"` to search across the codebase
 
 #### 1.3 Completeness Check
 

commands/multi-workflow.md

@@ -15,14 +15,14 @@ Structured development workflow with quality gates, MCP services, and multi-mode
 - Task to develop: $ARGUMENTS
 - Structured 6-phase workflow with quality gates
 - Multi-model collaboration: Codex (backend) + Gemini (frontend) + Claude (orchestration)
-- MCP service integration (ace-tool) for enhanced capabilities
+- MCP service integration (ace-tool, optional) for enhanced capabilities
 
 ## Your Role
 
 You are the **Orchestrator**, coordinating a multi-model collaborative system (Research → Ideation → Plan → Execute → Optimize → Review). Communicate concisely and professionally for experienced developers.
 
 **Collaborative Models**:
-- **ace-tool MCP** – Code retrieval + Prompt enhancement
+- **ace-tool MCP** (optional) – Code retrieval + Prompt enhancement
 - **Codex** – Backend logic, algorithms, debugging (**Backend authority, trustworthy**)
 - **Gemini** – Frontend UI/UX, visual design (**Frontend expert, backend opinions for reference only**)
 - **Claude (self)** – Orchestration, planning, execution, delivery
@@ -111,8 +111,8 @@ TaskOutput({ task_id: "<task_id>", block: true, timeout: 600000 })
 
 `[Mode: Research]` - Understand requirements and gather context:
 
-1. **Prompt Enhancement**: Call `mcp__ace-tool__enhance_prompt`, **replace original $ARGUMENTS with enhanced result for all subsequent Codex/Gemini calls**
-2. **Context Retrieval**: Call `mcp__ace-tool__search_context`
+1. **Prompt Enhancement** (if ace-tool MCP available): Call `mcp__ace-tool__enhance_prompt`, **replace original $ARGUMENTS with enhanced result for all subsequent Codex/Gemini calls**. If unavailable, use `$ARGUMENTS` as-is.
+2. **Context Retrieval** (if ace-tool MCP available): Call `mcp__ace-tool__search_context`. If unavailable, use built-in tools: `Glob` for file discovery, `Grep` for symbol search, `Read` for context gathering, `Task` (Explore agent) for deeper exploration.
 3. **Requirement Completeness Score** (0-10):
    - Goal clarity (0-3), Expected outcome (0-3), Scope boundaries (0-2), Constraints (0-2)
    - ≥7: Continue | <7: Stop, ask clarifying questions