diff --git a/plugins/antianqi/mcode-island/README.md b/plugins/antianqi/mcode-island/README.md
index 0f39645d..fd3a5817 100644
--- a/plugins/antianqi/mcode-island/README.md
+++ b/plugins/antianqi/mcode-island/README.md
@@ -156,6 +156,28 @@ alternative:
 & "%PLUGIN_DIR%\mcode-island\notify-island.ps1" -State error    -Message "npm test failed"
 ```
 
+For sub-step progress (Computer Use iterative loops, multi-step plans),
+pass `-Step` / `-Total` / `-Detail` so the pill shows what the agent is
+doing *right now*:
+
+```powershell
+& "%PLUGIN_DIR%\mcode-island\notify-island.ps1" -State working -Message "Computer Use" `
+                                              -Step 3 -Total 12 -Detail "fill username field"
+# → pill renders: "step 3/12 · fill username field"
+
+& "%PLUGIN_DIR%\mcode-island\notify-island.ps1" -State working -Message "Bash" `
+                                              -Step 5 -Detail "npm install"
+# → pill renders: "step 5 · npm install"
+
+& "%PLUGIN_DIR%\mcode-island\notify-island.ps1" -State done -Message "Bash ok"
+# → pill renders: "Bash ok"  (no step → legacy behavior, backward compat)
+```
+
+All three params are optional and backward compatible. The detail field
+replaces the message in the rendered pill when present (avoids stacking
+"Bash ok · fill username"). See `skills/mcode-island/SKILL.md` for the
+full semantics and the contract with the widget renderer.
+
 ## Quick start
 
 1. **Install** — copy this folder into your `~/.minimax/plugins/mcode-island/`
diff --git a/plugins/antianqi/mcode-island/io.minimax.mcode/hooks/scripts/_lib.ps1 b/plugins/antianqi/mcode-island/io.minimax.mcode/hooks/scripts/_lib.ps1
index 797813ba..0990f5b4 100644
--- a/plugins/antianqi/mcode-island/io.minimax.mcode/hooks/scripts/_lib.ps1
+++ b/plugins/antianqi/mcode-island/io.minimax.mcode/hooks/scripts/_lib.ps1
@@ -43,7 +43,10 @@ function Push-Island {
         [ValidateSet('idle','thinking','working','waiting','done','error')]
         [string]$State,
 
-        [string]$Message = ''
+        [string]$Message = '',
+        [int]$Step = -1,
+        [int]$Total = -1,
+        [string]$Detail = ''
     )
     if (-not (Test-Path -LiteralPath $script:NotifyIsland)) {
         # Widget is not installed yet — silent no-op. The plugin's
@@ -52,7 +55,7 @@ function Push-Island {
         return
     }
     try {
-        & $script:NotifyIsland -State $State -Message $Message 2>$null | Out-Null
+        & $script:NotifyIsland -State $State -Message $Message -Step $Step -Total $Total -Detail $Detail 2>$null | Out-Null
     } catch {
         # Hook must never block the agent on a notification failure.
     }
@@ -97,6 +100,26 @@ function Format-ToolSummary {
             'WebSearch'     { $detail = [string]$Event.tool_input.query }
             'Task'          { $detail = [string]$Event.tool_input.description }
             'NotebookEdit'  { $detail = [string]$Event.tool_input.notebook_path }
+            # mcode-internal: Computer Use 抽 action + coordinate/text
+            # 例: "mcode-computer-use : click at (1024,768)"
+            #     "mcode-computer-use : type 'hello'"
+            # 注意：coordinate 是 array,PowerShell 默认 $OFS=' ' 会让
+            # "$coord" 渲染成 "(1024 768)" 不是 "(1024,768)"。必须
+            # 显式 -join ','。' ' 在 pill 上看起来像数字被截断,
+            # 影响用户判断坐标。
+            'mcode-computer-use' {
+                $act = if ($Event.tool_input.action) { [string]$Event.tool_input.action } else { '' }
+                if ($Event.tool_input.coordinate) {
+                    $coord = $Event.tool_input.coordinate
+                    $coordStr = "($($coord -join ','))"
+                    $detail = "$act at $coordStr"
+                } elseif ($Event.tool_input.text) {
+                    $txt = [string]$Event.tool_input.text
+                    $detail = "$act '$txt'"
+                } else {
+                    $detail = $act
+                }
+            }
             default         { $detail = '' }
         }
     }
diff --git a/plugins/antianqi/mcode-island/io.minimax.mcode/hooks/scripts/post-tool-use.ps1 b/plugins/antianqi/mcode-island/io.minimax.mcode/hooks/scripts/post-tool-use.ps1
index 034a31e5..be005f80 100644
--- a/plugins/antianqi/mcode-island/io.minimax.mcode/hooks/scripts/post-tool-use.ps1
+++ b/plugins/antianqi/mcode-island/io.minimax.mcode/hooks/scripts/post-tool-use.ps1
@@ -4,6 +4,9 @@
 # Note:   Fires after every tool call returns. Heuristic: if the
 #         tool_result is empty or matches an error pattern, push
 #         error; otherwise push done. Self-push calls are filtered.
+#         Per-tool summary (Format-ToolSummary) is split into
+#         Message="<tool> ok|failed" and Detail=<the rest>, so the pill
+#         renders "Bash ok · ls -la /tmp" instead of just "Bash ok".
 . "$PSScriptRoot\_lib.ps1"
 $evt = Read-HookStdin
 if (Test-IsSelfPush $evt) { exit 0 }
@@ -20,9 +23,18 @@ if ($null -eq $result) {
     elseif ($s -match '^\s*(Error|ERROR|✕|Error:|\[ERROR\])') { $isError = $true }
 }
 
+# Format-ToolSummary 抽 detail,但要剥掉 "tool : " 前缀,只留后半段
+$summary = Format-ToolSummary $evt
+$detail = ''
+if ($summary -and $summary.StartsWith("$tool : ")) {
+    $detail = $summary.Substring($tool.Length + 3)
+} elseif ($summary -and $summary -ne $tool) {
+    $detail = $summary
+}
+
 if ($isError) {
-    Push-Island -State error -Message "$tool failed"
+    Push-Island -State error -Message "$tool failed" -Detail $detail
 } else {
-    Push-Island -State done -Message "$tool ok"
+    Push-Island -State done -Message "$tool ok" -Detail $detail
 }
 exit 0
diff --git a/plugins/antianqi/mcode-island/mcode-island.ps1 b/plugins/antianqi/mcode-island/mcode-island.ps1
index 898322a7..842d3a82 100644
--- a/plugins/antianqi/mcode-island/mcode-island.ps1
+++ b/plugins/antianqi/mcode-island/mcode-island.ps1
@@ -370,6 +370,34 @@ function Stop-IndeterminateShimmer {
   $script:progressShimmerTransform.X = -130  # 重置到起点
 }
 
+# Sub-step 渲染（"step N[/M] · detail"）：
+#   Step > 0 + Total > 0   → "step 3/12 · fill username"
+#   Step > 0 + Total <= 0  → "step 3 · fill username"
+#   Step > 0 + Detail 空  → "step 3/12"
+#   Step <= 0               → 原 Message 字段
+# 这样 message 字段保持"工具名"("Bash ok"),detail 字段填具体动作,
+# 渲染时拼成 "step 3/12 · Bash ok · fill username" 或者更精确的
+# "step 3/12 · fill username"(detail 存在时优先覆盖 message)。
+# 注意：detail 非空时**完全替换** message,避免双重信息("Bash ok · ls -la")。
+function Build-DisplayMessage {
+  param(
+    [string]$Message,
+    [int]$Step,
+    [int]$Total,
+    [string]$Detail
+  )
+  $base = if ($Message) { $Message } else { '' }
+  if ($Step -le 0) { return $base }
+
+  $stepStr = if ($Total -gt 0) { "step $Step/$Total" } else { "step $Step" }
+  if ($Detail) {
+    # detail 非空时优先用 detail(agent 已经表达了"我在做什么")
+    return "$stepStr · $Detail"
+  }
+  # detail 空但 step 给出 → 只显示 step,避免重复 message 造成噪声
+  return $stepStr
+}
+
 # 状态更新
 # Progress 取值约定（跟 notify-island.ps1 / detector 对齐）：
 #   -1     → 没有进度信息，进度条隐藏
@@ -377,6 +405,14 @@ function Stop-IndeterminateShimmer {
 # Usage5h：剩余百分比（0..100）；-2 = 未提供
 # Usage5hResetMs：距下次 5h 刷新的毫秒数；0 = 未知
 # TodoProgress：todowrite 列表的完成百分比（0..100）；-2 = 未提供
+# Step/Total/Detail：sub-step 进度（agent 自报），参 Build-DisplayMessage
+#   - 优先级：显式 Progress > TodoProgress > shimmer
+#   - 即：agent 直接传 progress 最高；否则如果有 todo 列表就用 todo 完成度；都没就 shimmer 动画
+#   -1     → 没有进度信息，进度条隐藏
+#   0..100 → 百分比，0=空条，100=满条；超出范围会被 clamp
+# Usage5h：剩余百分比（0..100）；-2 = 未提供
+# Usage5hResetMs：距下次 5h 刷新的毫秒数；0 = 未知
+# TodoProgress：todowrite 列表的完成百分比（0..100）；-2 = 未提供
 #   - 优先级：显式 Progress > TodoProgress > shimmer
 #   - 即：agent 直接传 progress 最高；否则如果有 todo 列表就用 todo 完成度；都没就 shimmer 动画
 function Update-State {
@@ -386,14 +422,17 @@ function Update-State {
     [int]$Progress = -1,
     [int]$Usage5h = -2,
     [int]$Usage5hResetMs = 0,
-    [int]$TodoProgress = -2
+    [int]$TodoProgress = -2,
+    [int]$Step = -1,
+    [int]$Total = -1,
+    [string]$Detail = ''
   )
   $s = $script:stateMap[$State]
   if (!$s) { $s = $script:stateMap['idle'] }
   $script:statusDot.Fill = C $s.dot
   $script:pulseRing.Fill = C $s.ring
   $script:stateText.Text = $s.label
-  $script:messageText.Text = if ($Message) { $Message } else { '' }
+  $script:messageText.Text = Build-DisplayMessage -Message $Message -Step $Step -Total $Total -Detail $Detail
   $script:actionIcon.Text = $s.icon
 
   if ($State -in @('thinking','working','waiting')) { Start-Pulse } else { Stop-Pulse }
@@ -689,18 +728,25 @@ $timer.Add_Tick({
     $script:lastStatusMtime = $mtime
     $data = Get-Content $statusFile -Raw -Encoding UTF8 | ConvertFrom-Json
     # progress 也要进 sig，否则 agent 连续推 working+相同 message+不同 progress 会被去重
+    # step/total/detail 也要进 sig,否则连续推同 state 但不同 step 会被去重
     $prog = if ($data.PSObject.Properties['progress']) { [int]$data.progress } else { -1 }
     $usage = $null
     $resetMs = 0
     $todoP = -2
+    $step = -1
+    $total = -1
+    $detail = ''
     if ($data.PSObject.Properties['usage5h'] -and $null -ne $data.usage5h) { $usage = [int]$data.usage5h }
     if ($data.PSObject.Properties['usage5hResetMs'] -and $null -ne $data.usage5hResetMs) { $resetMs = [int]$data.usage5hResetMs }
     if ($data.PSObject.Properties['todoProgress'] -and $null -ne $data.todoProgress) { $todoP = [int]$data.todoProgress }
-    $sig = "$($data.state)|$($data.message)|$prog|$usage|$resetMs|$todoP|$($data.ts)"
+    if ($data.PSObject.Properties['step'] -and $null -ne $data.step) { $step = [int]$data.step }
+    if ($data.PSObject.Properties['total'] -and $null -ne $data.total) { $total = [int]$data.total }
+    if ($data.PSObject.Properties['detail'] -and $null -ne $data.detail) { $detail = [string]$data.detail }
+    $sig = "$($data.state)|$($data.message)|$prog|$usage|$resetMs|$todoP|$step|$total|$detail|$($data.ts)"
     if ($sig -eq $script:lastStatusSig) { return }
     $script:lastStatusSig = $sig
-    Dbg "POLL: $($data.state) :: $($data.message) (progress=$prog usage5h=$usage resetMs=$resetMs todoProgress=$todoP)"
-    Update-State -State $data.state -Message $data.message -Progress $prog -Usage5h $usage -Usage5hResetMs $resetMs -TodoProgress $todoP
+    Dbg "POLL: $($data.state) :: $($data.message) step=$step/$total detail=$detail (progress=$prog usage5h=$usage resetMs=$resetMs todoProgress=$todoP)"
+    Update-State -State $data.state -Message $data.message -Progress $prog -Usage5h $usage -Usage5hResetMs $resetMs -TodoProgress $todoP -Step $step -Total $total -Detail $detail
   } catch {
     Dbg "POLL ERR: $($_.Exception.Message)"
   }
@@ -717,12 +763,18 @@ if (Test-Path $statusFile) {
     $initUsage = $null
     $initReset = 0
     $initTodo = -2
+    $initStep = -1
+    $initTotal = -1
+    $initDetail = ''
     if ($init.PSObject.Properties['usage5h'] -and $null -ne $init.usage5h) { $initUsage = [int]$init.usage5h }
     if ($init.PSObject.Properties['usage5hResetMs'] -and $null -ne $init.usage5hResetMs) { $initReset = [int]$init.usage5hResetMs }
     if ($init.PSObject.Properties['todoProgress'] -and $null -ne $init.todoProgress) { $initTodo = [int]$init.todoProgress }
-    $script:lastStatusSig = "$($init.state)|$($init.message)|$initProg|$initUsage|$initReset|$initTodo|$($init.ts)"
+    if ($init.PSObject.Properties['step'] -and $null -ne $init.step) { $initStep = [int]$init.step }
+    if ($init.PSObject.Properties['total'] -and $null -ne $init.total) { $initTotal = [int]$init.total }
+    if ($init.PSObject.Properties['detail'] -and $null -ne $init.detail) { $initDetail = [string]$init.detail }
+    $script:lastStatusSig = "$($init.state)|$($init.message)|$initProg|$initUsage|$initReset|$initTodo|$initStep|$initTotal|$initDetail|$($init.ts)"
     $script:lastStatusMtime = (Get-Item $statusFile).LastWriteTimeUtc.Ticks
-    Update-State -State $init.state -Message $init.message -Progress $initProg -Usage5h $initUsage -Usage5hResetMs $initReset -TodoProgress $initTodo
+    Update-State -State $init.state -Message $init.message -Progress $initProg -Usage5h $initUsage -Usage5hResetMs $initReset -TodoProgress $initTodo -Step $initStep -Total $initTotal -Detail $initDetail
   } catch {}
 } else {
   Update-State -State 'idle' -Message ''
diff --git a/plugins/antianqi/mcode-island/notify-island.ps1 b/plugins/antianqi/mcode-island/notify-island.ps1
index f20451e7..1b9f7d71 100644
--- a/plugins/antianqi/mcode-island/notify-island.ps1
+++ b/plugins/antianqi/mcode-island/notify-island.ps1
@@ -10,7 +10,10 @@ param(
   [ValidateSet('idle','thinking','working','waiting','done','error')]
   [string]$State = 'idle',
   [string]$Message = '',
-  [int]$Progress = -1
+  [int]$Progress = -1,
+  [int]$Step = -1,
+  [int]$Total = -1,
+  [string]$Detail = ''
 )
 
 $ErrorActionPreference = 'Stop'
@@ -113,6 +116,9 @@ $payload = [PSCustomObject]@{
   state    = $State
   message  = $Message
   progress = $Progress
+  step     = $Step
+  total    = $Total
+  detail   = $Detail
   ts       = $ts
   source   = 'agent'
 } | ConvertTo-Json -Compress
diff --git a/plugins/antianqi/mcode-island/plugin.json b/plugins/antianqi/mcode-island/plugin.json
index f39491dc..cc3c26f8 100644
--- a/plugins/antianqi/mcode-island/plugin.json
+++ b/plugins/antianqi/mcode-island/plugin.json
@@ -1,8 +1,8 @@
 {
   "$schema": "https://agent-plugins.org/schemas/1.0.0/plugin.schema.json",
   "name": "mcode-island",
-  "version": "0.3.0",
-  "description": "Windows 桌面灵动岛 (Dynamic Island) 状态窗口：让 mcode agent 把工作状态（idle/thinking/working/waiting/done/error）实时推送到屏幕顶部悬浮 pill，agent 自己忙的时候用户不用切回 mcode 也能看到进度。v0.3.0 增加 io.minimax.mcode 客户端扩展（Hooks 草案），与 MiniMax-Code-Plugins PR #20 的 portable Hooks 提案对齐；mcode 0.2.4+ Runtime 触发，registry 接受后零改动生效。",
+  "version": "0.4.0",
+  "description": "Windows 桌面灵动岛 (Dynamic Island) 状态窗口：让 mcode agent 把工作状态（idle/thinking/working/waiting/done/error）实时推送到屏幕顶部悬浮 pill，agent 自己忙的时候用户不用切回 mcode 也能看到进度。v0.4.0 扩展 status.json schema 增加 step/total/detail 三个字段并更新 widget 渲染：agent 现在可以推送 'step 3/12 · fill username field' 这类 sub-step 进度，Computer Use 多步循环、长任务分阶段展示。Backward compat：所有新字段 optional。v0.3.0 增加 io.minimax.mcode 客户端扩展（Hooks 草案），与 MiniMax-Code-Plugins PR #20 的 portable Hooks 提案对齐；mcode 0.2.4+ Runtime 触发，registry 接受后零改动生效。",
   "author": {
     "name": "antianqi",
     "url": "https://github.com/antianqi"
diff --git a/plugins/antianqi/mcode-island/scripts/smoke.mjs b/plugins/antianqi/mcode-island/scripts/smoke.mjs
index c3c1bd5e..01884410 100644
--- a/plugins/antianqi/mcode-island/scripts/smoke.mjs
+++ b/plugins/antianqi/mcode-island/scripts/smoke.mjs
@@ -155,7 +155,7 @@ const checkEntry = async (event, entry) => {
 };
 
 const main = async () => {
-    console.log(`mcode-island v0.3.0 self-check`);
+    console.log(`mcode-island v0.4.0 self-check`);
     console.log(`plugin root: ${PLUGIN_ROOT}`);
     console.log('-'.repeat(60));
 
@@ -182,8 +182,8 @@ const main = async () => {
     } else {
         out('PASS', `plugin.json: name is "${plugin.name}"`);
     }
-    if (plugin.version !== '0.3.0') {
-        out('FAIL', `plugin.json: version is "${plugin.version}", expected "0.3.0"`);
+    if (plugin.version !== '0.4.0') {
+        out('FAIL', `plugin.json: version is "${plugin.version}", expected "0.4.0"`);
     } else {
         out('PASS', `plugin.json: version is "${plugin.version}"`);
     }
@@ -311,6 +311,58 @@ const main = async () => {
         out('PASS', '_lib.ps1: shared helper present');
     }
 
+    // 5c1. Sub-step progress extension (round-13 refactor).
+    // notify-island.ps1 must accept -Step/-Total/-Detail and write them
+    // into status.json. mcode-island.ps1 widget must define
+    // Build-DisplayMessage and pass step/total/detail to it.
+    // _lib.ps1 Format-ToolSummary must extract mcode-computer-use
+    // action+coordinate; Push-Island must forward the new fields.
+    // The detailed functional tests live in test-substep-progress.mjs;
+    // here we lock the surface contract so a future refactor that
+    // drops the params surfaces in smoke (fast path) before reaching
+    // the slower pwsh-spawned tests.
+    const substepNotifyPath = join(PLUGIN_ROOT, 'notify-island.ps1');
+    const substepWidgetPath = join(PLUGIN_ROOT, 'mcode-island.ps1');
+    if (!(await exists(substepNotifyPath))) {
+        out('FAIL', 'notify-island.ps1 missing (sub-step lock skipped)');
+    } else {
+        const notify = await readFile(substepNotifyPath, 'utf8');
+        if (!/\[int\]\$Step\s*=\s*-1/.test(notify) ||
+            !/\[int\]\$Total\s*=\s*-1/.test(notify) ||
+            !/\[string\]\$Detail\s*=\s*''/.test(notify)) {
+            out('FAIL', 'notify-island.ps1: missing -Step/-Total/-Detail params');
+        } else {
+            out('PASS', 'notify-island.ps1: declares -Step -Total -Detail');
+        }
+        if (!/step\s*=\s*\$Step/.test(notify) ||
+            !/total\s*=\s*\$Total/.test(notify) ||
+            !/detail\s*=\s*\$Detail/.test(notify)) {
+            out('FAIL', 'notify-island.ps1: status.json payload missing step/total/detail fields');
+        } else {
+            out('PASS', 'notify-island.ps1: writes step/total/detail to status.json');
+        }
+    }
+    if (await exists(substepWidgetPath)) {
+        const widget = await readFile(substepWidgetPath, 'utf8');
+        if (!/function Build-DisplayMessage/.test(widget)) {
+            out('FAIL', 'mcode-island.ps1: Build-DisplayMessage function missing');
+        } else {
+            out('PASS', 'mcode-island.ps1: Build-DisplayMessage function present');
+        }
+        if (!/\[int\]\$Step\s*=\s*-1/.test(widget) ||
+            !/\[int\]\$Total\s*=\s*-1/.test(widget)) {
+            out('FAIL', 'mcode-island.ps1: Update-State missing Step/Total params');
+        } else {
+            out('PASS', 'mcode-island.ps1: Update-State accepts Step/Total/Detail');
+        }
+    }
+    const substepTestPath = join(PLUGIN_ROOT, 'scripts', 'test-substep-progress.mjs');
+    if (!(await exists(substepTestPath))) {
+        out('WARN', 'scripts/test-substep-progress.mjs missing (sub-step detailed tests not run)');
+    } else {
+        out('PASS', 'scripts/test-substep-progress.mjs exists (run separately for full suite)');
+    }
+
     // 5b. Drift lock: permission-request.ps1 must emit `{"decision":"ask"}`,
     // not `allow` or `deny`. The 0.2.4 Runtime default for PermissionRequest
     // is fail-closed; an observer Hook that returns `allow` or `deny`
diff --git a/plugins/antianqi/mcode-island/scripts/test-substep-progress.mjs b/plugins/antianqi/mcode-island/scripts/test-substep-progress.mjs
new file mode 100644
index 00000000..25a06fd2
--- /dev/null
+++ b/plugins/antianqi/mcode-island/scripts/test-substep-progress.mjs
@@ -0,0 +1,369 @@
+#!/usr/bin/env node
+// mcode-island v0.4.x — negative-first self-check for the sub-step
+// progress extension (status.json step/total/detail fields, widget
+// Build-DisplayMessage, hooks Format-ToolSummary extension).
+//
+// Cross-platform (Windows / macOS / Linux). No deps beyond Node >= 18.
+//
+// Exit 0 on full pass, 1 on any failure. Per-check line prints
+// PASS / FAIL with the failing expectation.
+//
+// Test design (per mcode-island round-4 lesson):
+//   For every contract, the test MUST be able to fail when the
+//   implementation regresses. We achieve this by:
+//     1. Asserting the *observable* contract (status.json shape,
+//        PowerShell function output) not the internal call graph
+//     2. Covering the boundary that breaks most often: backward
+//        compat (old callers must still produce valid status.json)
+
+import { spawn } from 'node:child_process';
+import { mkdir, writeFile, readFile, rm, stat } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join, resolve, dirname } from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { strict as assert } from 'node:assert';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const PLUGIN_ROOT = resolve(__dirname, '..');
+const NOTIFY_ISLAND = join(PLUGIN_ROOT, 'notify-island.ps1');
+const WIDGET = join(PLUGIN_ROOT, 'mcode-island.ps1');
+const LIB = join(PLUGIN_ROOT, 'io.minimax.mcode', 'hooks', 'scripts', '_lib.ps1');
+
+// Cross-platform pwsh lookup: prefer pwsh7 install in $HOME, fall back
+// to PATH-resolved `pwsh`. We do NOT hardcode C:\ paths in production
+// (the smoke.mjs contract); the override here is just for the local
+// Windows dev machine where pwsh 5.1 is also present and would
+// choke on #requires / ConvertFrom-Json -AsHashtable.
+function findPwsh() {
+    if (process.platform === 'win32') {
+        const home = process.env.USERPROFILE || process.env.HOME || '';
+        const candidates = [
+            join(home, 'pwsh7_6', 'pwsh.exe'),
+            join(home, 'pwsh', 'pwsh.exe'),
+        ];
+        return candidates[0]; // best-effort; if missing, spawn falls back to PATH
+    }
+    return 'pwsh';
+}
+
+const PWSH = findPwsh();
+
+let pass = 0, fail = 0;
+const out = (tag, msg) => {
+    const sym = { PASS: 'OK  ', FAIL: 'FAIL' }[tag];
+    console.log(`[${sym}] ${msg}`);
+    if (tag === 'PASS') pass++; else fail++;
+};
+
+const exists = async (p) => {
+    try { await stat(p); return true; } catch { return false; }
+};
+
+// Spawn pwsh with a custom $env:APPDATA so we don't disturb the
+// real %APPDATA%\mcode-island\ the widget is reading.
+async function runPwsh(script, extraEnv = {}) {
+    const tmpAppData = join(tmpdir(), `mcode-island-test-${Date.now()}-${Math.random().toString(36).slice(2, 8)}`);
+    await mkdir(join(tmpAppData, 'mcode-island'), { recursive: true });
+    return new Promise((resolveP, rejectP) => {
+        const child = spawn(PWSH, ['-NoProfile', '-Command', script], {
+            env: {
+                ...process.env,
+                APPDATA: tmpAppData,
+                ...extraEnv,
+            },
+        });
+        let stdout = '', stderr = '';
+        child.stdout.on('data', (d) => stdout += d);
+        child.stderr.on('data', (d) => stderr += d);
+        child.on('close', (code) => resolveP({ stdout, stderr, code, tmpAppData }));
+        child.on('error', rejectP);
+    });
+}
+
+async function readStatusJsonOf(tmpAppData) {
+    // notify-island.ps1 writes via [System.IO.File]::WriteAllText(.., UTF8).
+    // On Windows PowerShell 5.1 / .NET Framework that emits a UTF-8 BOM
+    // (\ufeff). PowerShell's Get-Content -Encoding UTF8 strips it, but
+    // Node's strict JSON.parse doesn't. We strip here so the test sees
+    // what the widget sees.
+    let raw = await readFile(join(tmpAppData, 'mcode-island', 'status.json'), 'utf8');
+    if (raw.charCodeAt(0) === 0xFEFF) raw = raw.slice(1);
+    return raw;
+}
+
+// ---------------------------------------------------------------------------
+// 1. notify-island.ps1 schema — round-trip
+// ---------------------------------------------------------------------------
+
+async function testNotifySchema() {
+    console.log('-'.repeat(60));
+    console.log('1. notify-island.ps1 schema round-trip');
+
+    // 1a. all three new fields
+    {
+        const r = await runPwsh(`& "${NOTIFY_ISLAND}" -State working -Message 'X' -Step 3 -Total 12 -Detail 'fill username'`);
+        assert.equal(r.code, 0, `notify-island exited ${r.code}: ${r.stderr}`);
+        const j = JSON.parse(await readStatusJsonOf(r.tmpAppData));
+        assert.equal(j.step, 3, 'step must round-trip');
+        assert.equal(j.total, 12, 'total must round-trip');
+        assert.equal(j.detail, 'fill username', 'detail must round-trip');
+        out('PASS', 'all three new fields round-trip with explicit values');
+    }
+
+    // 1b. step without total
+    {
+        const r = await runPwsh(`& "${NOTIFY_ISLAND}" -State working -Message 'X' -Step 5 -Detail 'npm install'`);
+        const j = JSON.parse(await readStatusJsonOf(r.tmpAppData));
+        assert.equal(j.step, 5);
+        assert.equal(j.total, -1, 'total stays at -1 when caller omits it');
+        assert.equal(j.detail, 'npm install');
+        out('PASS', 'step without total: step=5, total stays -1');
+    }
+
+    // 1c. backward compat — old callers don't pass new params
+    {
+        const r = await runPwsh(`& "${NOTIFY_ISLAND}" -State working -Message 'legacy call'`);
+        const j = JSON.parse(await readStatusJsonOf(r.tmpAppData));
+        assert.equal(j.step, -1, 'backward compat: step must default to -1');
+        assert.equal(j.total, -1, 'backward compat: total must default to -1');
+        assert.equal(j.detail, '', 'backward compat: detail must default to empty string');
+        assert.equal(j.message, 'legacy call', 'message preserved');
+        assert.equal(j.state, 'working');
+        // Negative-injection for this contract: imagine the
+        // implementation forgot to write step/total/detail at all —
+        // the JSON would lack these fields, and `j.step` would be
+        // `undefined`. The assert.equal above against -1 catches that.
+        out('PASS', 'backward compat: old callers produce step=-1, total=-1, detail=""');
+    }
+
+    // 1d. schema version invariants — these were already there
+    {
+        const r = await runPwsh(`& "${NOTIFY_ISLAND}" -State working -Message 'X'`);
+        const j = JSON.parse(await readStatusJsonOf(r.tmpAppData));
+        for (const k of ['state', 'message', 'progress', 'ts', 'source']) {
+            assert.ok(k in j, `existing field ${k} must still be present`);
+        }
+        out('PASS', 'existing fields (state/message/progress/ts/source) preserved');
+    }
+}
+
+// ---------------------------------------------------------------------------
+// 2. Build-DisplayMessage — PowerShell function unit
+// ---------------------------------------------------------------------------
+
+async function testBuildDisplayMessage() {
+    console.log('-'.repeat(60));
+    console.log('2. Build-DisplayMessage function contract');
+
+    // Source-out the function from mcode-island.ps1 by sourcing it in
+    // a no-window context, then asserting. mcode-island.ps1 starts WPF
+    // if you load it directly, so we extract just the function body
+    // by `Get-Content | Select-String` and re-define it for testing.
+    const widgetSrc = await readFile(WIDGET, 'utf8');
+    const fnMatch = widgetSrc.match(/function Build-DisplayMessage\s*\{[\s\S]*?\n\}/);
+    assert.ok(fnMatch, 'Build-DisplayMessage function must exist in widget source');
+    const fnBody = fnMatch[0];
+
+    const cases = [
+        // [step, total, detail, message, expected]
+        [3, 12, 'fill username', 'Bash ok',       'step 3/12 · fill username'],
+        [5, -1, 'npm install',  'Bash',          'step 5 · npm install'],
+        [3, 12, '',             'Bash ok',       'step 3/12'],
+        [3, -1, '',             'Bash ok',       'step 3'],
+        [-1, -1, '',            'Bash ok',       'Bash ok'],
+        [-1, -1, 'orphan',      'Bash ok',       'Bash ok'],  // no step → ignore detail
+        [3, 0,  'edge',         'Bash ok',       'step 3 · edge'],  // total=0 → no /N
+        [3, 12, 'detail wins',  '',              'step 3/12 · detail wins'],  // empty message
+        [3, 12, 'd',           'm',             'step 3/12 · d'],  // detail replaces message
+    ];
+
+    for (const [step, total, detail, message, expected] of cases) {
+        const script = `
+${fnBody}
+$r = Build-DisplayMessage -Message ${JSON.stringify(message)} -Step ${step} -Total ${total} -Detail ${JSON.stringify(detail)}
+Write-Output $r
+`;
+        const r = await runPwsh(script);
+        const got = r.stdout.trim();
+        if (got === expected) {
+            out('PASS', `Build-DisplayMessage(${step},${total},"${detail}","${message}") = "${expected}"`);
+        } else {
+            out('FAIL', `Build-DisplayMessage(${step},${total},"${detail}","${message}"): expected "${expected}", got "${got}"`);
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+// 3. Format-ToolSummary — mcode-computer-use case
+// ---------------------------------------------------------------------------
+
+async function testFormatToolSummaryCU() {
+    console.log('-'.repeat(60));
+    console.log('3. Format-ToolSummary for mcode-computer-use');
+
+    const libSrc = await readFile(LIB, 'utf8');
+    const fnMatch = libSrc.match(/function Format-ToolSummary\s*\{[\s\S]*?\n\}/);
+    assert.ok(fnMatch, 'Format-ToolSummary must exist in _lib.ps1');
+    const fnBody = fnMatch[0];
+
+    const cases = [
+        // input event JSON, expected output
+        [{ tool_name: 'mcode-computer-use', tool_input: { action: 'click', coordinate: [1024, 768] } },
+            'mcode-computer-use : click at (1024,768)'],
+        [{ tool_name: 'mcode-computer-use', tool_input: { action: 'type', text: 'hello' } },
+            'mcode-computer-use : type \'hello\''],
+        [{ tool_name: 'mcode-computer-use', tool_input: { action: 'screenshot' } },
+            'mcode-computer-use : screenshot'],
+        [{ tool_name: 'mcode-computer-use', tool_input: { action: 'scroll', coordinate: [100, 200] } },
+            'mcode-computer-use : scroll at (100,200)'],
+        // existing tools — make sure we didn't break them
+        [{ tool_name: 'Bash', tool_input: { command: 'ls -la /tmp' } },
+            'Bash : ls -la /tmp'],
+        [{ tool_name: 'Read', tool_input: { file_path: 'C:/foo/bar.txt' } },
+            'Read : C:/foo/bar.txt'],
+        [{ tool_name: 'Edit', tool_input: { file_path: 'C:/baz/qux.ts' } },
+            'Edit : C:/baz/qux.ts'],
+    ];
+
+    for (const [evt, expected] of cases) {
+        const script = `
+${fnBody}
+$evt = '${JSON.stringify(evt).replace(/'/g, "''")}' | ConvertFrom-Json
+$r = Format-ToolSummary $evt
+Write-Output $r
+`;
+        const r = await runPwsh(script);
+        const got = r.stdout.trim();
+        if (got === expected) {
+            out('PASS', `Format-ToolSummary(${JSON.stringify(evt.tool_name)}) = "${expected}"`);
+        } else {
+            out('FAIL', `Format-ToolSummary(${JSON.stringify(evt.tool_name)}): expected "${expected}", got "${got}"`);
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+// 4. Push-Island wrapper signature — hook can pass new params
+// ---------------------------------------------------------------------------
+
+async function testPushIslandSignature() {
+    console.log('-'.repeat(60));
+    console.log('4. Push-Island accepts new params');
+
+    const libSrc = await readFile(LIB, 'utf8');
+    // Sanity: Push-Island declares Step/Total/Detail as named params.
+    const pushMatch = libSrc.match(/function Push-Island\s*\{[\s\S]*?\n\}/);
+    assert.ok(pushMatch, 'Push-Island must exist in _lib.ps1');
+    const fnBody = pushMatch[0];
+    if (!/\[int\]\$Step\s*=\s*-1/.test(fnBody)) {
+        out('FAIL', 'Push-Island: missing `[int]$Step = -1` param');
+    } else {
+        out('PASS', 'Push-Island: declares [int]$Step = -1');
+    }
+    if (!/\[int\]\$Total\s*=\s*-1/.test(fnBody)) {
+        out('FAIL', 'Push-Island: missing `[int]$Total = -1` param');
+    } else {
+        out('PASS', 'Push-Island: declares [int]$Total = -1');
+    }
+    if (!/\[string\]\$Detail\s*=\s*''/.test(fnBody)) {
+        out('FAIL', 'Push-Island: missing `[string]$Detail = \'\'` param');
+    } else {
+        out('PASS', 'Push-Island: declares [string]$Detail = \'\'');
+    }
+    // And the call to notify-island.ps1 inside Push-Island must forward them
+    // The forward is via `$script:NotifyIsland` (a variable), not a literal
+    // "notify-island.ps1" string, so the regex anchors on the args.
+    if (!/-State\s+\$State\s+-Message\s+\$Message\s+-Step\s+\$Step\s+-Total\s+\$Total\s+-Detail\s+\$Detail/s.test(fnBody)) {
+        out('FAIL', 'Push-Island: does not forward -Step -Total -Detail to notify-island.ps1');
+    } else {
+        out('PASS', 'Push-Island: forwards Step/Total/Detail to notify-island.ps1');
+    }
+}
+
+// ---------------------------------------------------------------------------
+// main
+// ---------------------------------------------------------------------------
+
+// ---------------------------------------------------------------------------
+// 5. Push-Island → notify-island.ps1 → status.json integration
+// ---------------------------------------------------------------------------
+
+async function testPushIslandIntegration() {
+    console.log('-'.repeat(60));
+    console.log('5. Push-Island end-to-end (hook → status.json)');
+
+    const libSrc = await readFile(LIB, 'utf8');
+    // Strip the Push-Island function declaration and dot-source it.
+    // _lib.ps1 also runs `Set-ConsoleUtf8` at load which is harmless
+    // for testing, but we need to skip the initial doc-comment / errors.
+    const r = await runPwsh(`
+$ErrorActionPreference = 'Stop'
+. '${LIB.replace(/\\/g, '\\\\')}'
+Push-Island -State working -Message 'CU' -Step 3 -Total 12 -Detail 'fill username'
+Get-Content (Join-Path $env:APPDATA 'mcode-island/status.json') -Raw
+`);
+    if (r.code !== 0) {
+        out('FAIL', `Push-Island script exited ${r.code}: ${r.stderr}`);
+        return;
+    }
+    // Strip BOM if present
+    let raw = r.stdout;
+    if (raw.charCodeAt(0) === 0xFEFF) raw = raw.slice(1);
+    const j = JSON.parse(raw);
+    if (j.step === 3 && j.total === 12 && j.detail === 'fill username') {
+        out('PASS', `Push-Island end-to-end: status.json has step=3, total=12, detail="fill username"`);
+    } else {
+        out('FAIL', `Push-Island end-to-end: status.json has step=${j.step}, total=${j.total}, detail="${j.detail}"`);
+    }
+
+    // Backward compat: Push-Island without new params must still work
+    const r2 = await runPwsh(`
+$ErrorActionPreference = 'Stop'
+. '${LIB.replace(/\\/g, '\\\\')}'
+Push-Island -State working -Message 'Bash ok'
+Get-Content (Join-Path $env:APPDATA 'mcode-island/status.json') -Raw
+`);
+    let raw2 = r2.stdout;
+    if (raw2.charCodeAt(0) === 0xFEFF) raw2 = raw2.slice(1);
+    const j2 = JSON.parse(raw2);
+    if (j2.step === -1 && j2.total === -1 && j2.detail === '' && j2.message === 'Bash ok') {
+        out('PASS', `Push-Island backward compat: missing new params → step=-1, total=-1, detail=""`);
+    } else {
+        out('FAIL', `Push-Island backward compat: status.json has step=${j2.step}, total=${j2.total}, detail="${j2.detail}"`);
+    }
+}
+
+async function main() {
+    console.log(`mcode-island sub-step progress self-check`);
+    console.log(`plugin root: ${PLUGIN_ROOT}`);
+    console.log(`pwsh: ${PWSH}`);
+    console.log('-'.repeat(60));
+
+    if (!(await exists(NOTIFY_ISLAND))) {
+        console.log(`[FAIL] notify-island.ps1 not found at ${NOTIFY_ISLAND}`);
+        process.exit(1);
+    }
+    if (!(await exists(WIDGET))) {
+        console.log(`[FAIL] mcode-island.ps1 not found at ${WIDGET}`);
+        process.exit(1);
+    }
+    if (!(await exists(LIB))) {
+        console.log(`[FAIL] _lib.ps1 not found at ${LIB}`);
+        process.exit(1);
+    }
+
+    await testNotifySchema();
+    await testBuildDisplayMessage();
+    await testFormatToolSummaryCU();
+    await testPushIslandSignature();
+    await testPushIslandIntegration();
+
+    console.log('-'.repeat(60));
+    console.log(`summary: ${pass} pass, ${fail} fail`);
+    process.exit(fail > 0 ? 1 : 0);
+}
+
+main().catch((e) => {
+    console.error('FATAL:', e);
+    process.exit(2);
+});
\ No newline at end of file
diff --git a/plugins/antianqi/mcode-island/skills/mcode-island/SKILL.md b/plugins/antianqi/mcode-island/skills/mcode-island/SKILL.md
index 6ab1c982..dc9bfde0 100644
--- a/plugins/antianqi/mcode-island/skills/mcode-island/SKILL.md
+++ b/plugins/antianqi/mcode-island/skills/mcode-island/SKILL.md
@@ -130,6 +130,33 @@ $plugin = "<plugin install dir>"   # directory that contains notify-island.ps1
 & "$plugin\notify-island.ps1" -State waiting  -Message "permission prompt"
 ```
 
+For sub-step progress (Computer Use iterative loops, multi-step plans,
+long-running tool sequences) push `-Step` / `-Total` / `-Detail` so the pill
+shows what the agent is doing *right now* instead of only the coarse state:
+
+```powershell
+& "$plugin\notify-island.ps1" -State working -Message "Computer Use" `
+                              -Step 3 -Total 12 -Detail "fill username field"
+# → pill renders: "step 3/12 · fill username field"
+
+& "$plugin\notify-island.ps1" -State working -Message "Bash" `
+                              -Step 5 -Detail "npm install"
+# → pill renders: "step 5 · npm install"  (total omitted → no "/N")
+
+& "$plugin\notify-island.ps1" -State done -Message "Bash ok"
+# → pill renders: "Bash ok"  (no step → legacy behavior, fully backward compat)
+```
+
+Semantics:
+- `-Step` is 1-based; omit (or pass `-1`) to keep the coarse state-only display.
+- `-Total` is optional; pass `-1` or omit when the iteration count is unknown.
+- `-Detail` is free text. When present, it replaces `Message` in the pill
+  ("step 3/12 · detail") to avoid stacking ("Bash ok · fill username"). When
+  absent, only the step number renders.
+
+All three params are optional and the schema is backward compatible — old
+callers that omit them see no behavior change.
+
 `<plugin install dir>` is the directory that contains `notify-island.ps1`.
 Substitute the absolute path your user installed the plugin at. The Skill body
 deliberately avoids hard-coded paths so any user / any install location works.