feat: add Sync Variants feature to copy config between variants

AGENTS.md

@@ -1,5 +1,7 @@
 # Repository Guidelines
 
+**Generated:** 2026-01-04 | **Commit:** 649f42a | **Branch:** main
+
 ## Project Structure
 
 ```
@@ -102,12 +104,12 @@ Location: `~/.local/bin/<variant>`
 
 ### Provider Auth Modes
 
-| Provider | Auth Mode | Key Variable |
-|----------|-----------|--------------|
-| zai, minimax, custom | API Key | `ANTHROPIC_API_KEY` |
-| openrouter | Auth Token | `ANTHROPIC_AUTH_TOKEN` |
-| ccrouter | Optional | placeholder token |
-| mirror | None | user authenticates normally |
+| Provider             | Auth Mode  | Key Variable                |
+| -------------------- | ---------- | --------------------------- |
+| zai, minimax, custom | API Key    | `ANTHROPIC_API_KEY`         |
+| openrouter           | Auth Token | `ANTHROPIC_AUTH_TOKEN`      |
+| ccrouter             | Optional   | placeholder token           |
+| mirror               | None       | user authenticates normally |
 
 ### Model Mapping (env vars)
 
@@ -118,14 +120,18 @@ Location: `~/.local/bin/<variant>`
 
 ## Team Mode
 
-Team mode patches `cli.js` to enable Task* tools for multi-agent collaboration.
+Team mode patches `cli.js` to enable Task\* tools for multi-agent collaboration.
 
 ### How It Works
 
 ```javascript
 // Target function in cli.js
-function sU() { return !1; }  // disabled (default)
-function sU() { return !0; }  // enabled (patched)
+function sU() {
+  return !1;
+} // disabled (default)
+function sU() {
+  return !0;
+} // enabled (patched)
 ```
 
 - Backup stored at `cli.js.backup` before patching
@@ -140,31 +146,33 @@ function sU() { return !0; }  // enabled (patched)
 
 ### Agent Identity Env Vars
 
-| Variable | Purpose |
-|----------|---------|
-| `CLAUDE_CODE_TEAM_NAME` | Team namespace for task storage |
-| `CLAUDE_CODE_AGENT_ID` | Unique identifier for this agent |
+| Variable                 | Purpose                             |
+| ------------------------ | ----------------------------------- |
+| `CLAUDE_CODE_TEAM_NAME`  | Team namespace for task storage     |
+| `CLAUDE_CODE_AGENT_ID`   | Unique identifier for this agent    |
 | `CLAUDE_CODE_AGENT_TYPE` | Agent role: `team-lead` or `worker` |
 
 ## Provider Blocked Tools
 
 Providers can block tools via TweakCC toolsets. Defined in `src/brands/*.ts`.
 
 **zai blocked tools:**
+
 ```typescript
 export const ZAI_BLOCKED_TOOLS = [
-  'mcp__4_5v_mcp__analyze_image',      // Server-injected
+  'mcp__4_5v_mcp__analyze_image', // Server-injected
   'mcp__milk_tea_server__claim_milk_tea_coupon',
   'mcp__web_reader__webReader',
-  'WebSearch',                          // Use zai-cli search
-  'WebFetch',                           // Use zai-cli read
+  'WebSearch', // Use zai-cli search
+  'WebFetch', // Use zai-cli read
 ];
 ```
 
 **minimax blocked tools:**
+
 ```typescript
 export const MINIMAX_BLOCKED_TOOLS = [
-  'WebSearch',  // Use mcp__MiniMax__web_search
+  'WebSearch', // Use mcp__MiniMax__web_search
 ];
 ```
 
@@ -179,15 +187,15 @@ export const MINIMAX_BLOCKED_TOOLS = [
 
 ## Common Development Tasks
 
-| Task | Location |
-|------|----------|
-| Add/update provider | `src/providers/index.ts` |
-| Add/update brand theme | `src/brands/*.ts` |
-| Add blocked tools | `src/brands/zai.ts` or `minimax.ts` → `*_BLOCKED_TOOLS` |
-| Modify prompt pack overlays | `src/core/prompt-pack/providers/*.ts` |
-| Add build step | `src/core/variant-builder/steps/` |
-| Add TUI screen | `src/tui/screens/` + `app.tsx` + `router/routes.ts` |
-| Add team pack prompt | `src/team-pack/*.md` + `TEAM_PACK_FILES` in `index.ts` |
+| Task                        | Location                                                |
+| --------------------------- | ------------------------------------------------------- |
+| Add/update provider         | `src/providers/index.ts`                                |
+| Add/update brand theme      | `src/brands/*.ts`                                       |
+| Add blocked tools           | `src/brands/zai.ts` or `minimax.ts` → `*_BLOCKED_TOOLS` |
+| Modify prompt pack overlays | `src/core/prompt-pack/providers/*.ts`                   |
+| Add build step              | `src/core/variant-builder/steps/`                       |
+| Add TUI screen              | `src/tui/screens/` + `app.tsx` + `router/routes.ts`     |
+| Add team pack prompt        | `src/team-pack/*.md` + `TEAM_PACK_FILES` in `index.ts`  |
 
 ## Debugging & Verification
 
@@ -277,6 +285,7 @@ npm test -- --test-name-pattern="TUI"      # TUI tests only
 ```
 
 Key test files:
+
 - `test/e2e/creation.test.ts` - Variant creation for all providers
 - `test/e2e/team-mode.test.ts` - Team mode + team pack
 - `test/e2e/blocked-tools.test.ts` - Provider blocked tools

src/core/AGENTS.md

@@ -0,0 +1,41 @@
+# Core Module
+
+Public API for variant management. All CLI/TUI operations flow through `index.ts`.
+
+## Public API
+
+| Export                                     | Purpose                                                  |
+| ------------------------------------------ | -------------------------------------------------------- |
+| `createVariant()` / `createVariantAsync()` | Build new variant (sync for CLI, async for TUI progress) |
+| `updateVariant()` / `updateVariantAsync()` | Reinstall npm + reapply config                           |
+| `removeVariant()`                          | Delete variant directory                                 |
+| `doctor()`                                 | Health check all variants                                |
+| `listVariants()`                           | Enumerate `~/.cc-mirror/`                                |
+| `tweakVariant()`                           | Launch tweakcc UI                                        |
+
+## Module Map
+
+| File               | Role                                               |
+| ------------------ | -------------------------------------------------- |
+| `constants.ts`     | `DEFAULT_ROOT`, `DEFAULT_BIN_DIR`, `DEFAULT_NPM_*` |
+| `paths.ts`         | `expandTilde()` helper                             |
+| `fs.ts`            | `ensureDir()`, `writeJsonFile()`                   |
+| `variants.ts`      | Load/list variant metadata                         |
+| `wrapper.ts`       | Generate wrapper shell scripts                     |
+| `tweakcc.ts`       | TweakCC config management                          |
+| `claude-config.ts` | `.claude.json` generation                          |
+| `install.ts`       | npm package installation                           |
+| `prompt-pack.ts`   | Provider prompt overlay resolution                 |
+| `skills.ts`        | Skill installation (dev-browser)                   |
+| `shell-env.ts`     | Write API keys to shell profile                    |
+
+## Subdirectories
+
+- `variant-builder/` - Step-based build orchestration (see its AGENTS.md)
+- `prompt-pack/` - Per-provider system prompt overlays
+
+## Conventions
+
+- Sync functions for CLI, async variants for TUI (yields to event loop)
+- All paths resolved via `expandTilde()` before use
+- Errors thrown as `Error` with descriptive message

src/core/index.ts

@@ -18,6 +18,8 @@ import type {
 
 export { DEFAULT_ROOT, DEFAULT_BIN_DIR, DEFAULT_NPM_PACKAGE, DEFAULT_NPM_VERSION };
 export { expandTilde } from './paths.js';
+export { syncVariants, syncVariantsAsync, createConfigBackup, restoreConfigBackup } from './sync.js';
+export type { SyncItem, SyncOptions, SyncResult, SyncItemResult } from './sync.js';
 
 export const createVariant = (params: CreateVariantParams): CreateVariantResult => {
   return new VariantBuilder(false).build(params);