docs: correct the plan's no-arg ipc open and the head pipe

Quickshell 0.3.1 IPC requires every declared argument, so the plan's
`ipc call drawer open` with no page fails; the page-less grid entry is
the zero-argument `toggle`. Also records that `... | head` races
timeout and kills the shell early, so verification uses a file redirect.

1 files changed, 20 insertions, 6 deletions

diff --git a/docs/superpowers/plans/2026-09-14-desktop-shell.md b/docs/superpowers/plans/2026-09-14-desktop-shell.md
index d067b15..3476db6 100644
--- a/docs/superpowers/plans/2026-09-14-desktop-shell.md
+++ b/docs/superpowers/plans/2026-09-14-desktop-shell.md
@@ -34,6 +34,16 @@ Verification in this plan is therefore: start the shell in the foreground with a
 timeout, read what it printed, and kill by exact name. Anything visual is for
 the user to look at, not for a screenshot.
 
+**Erratum (post-Task-4).** Two corrections found during execution, applying to
+every verification block below:
+
+- The `... 2>&1 | head -20` form races `timeout` and kills the shell early.
+  Use a file redirect instead: `timeout N qs -p desktop > /tmp/opencode/x.log
+  2>&1 &` then `sleep`, probe, `wait`, then read the log.
+- Quickshell 0.3.1 IPC requires every declared argument present, so
+  `ipc call drawer open` with no page name fails. The page-less grid entry is
+  the zero-argument `ipc call drawer toggle`; `open` always takes a page name.
+
 ## File structure
 
 ```
@@ -715,12 +725,16 @@ ShellRoot {
     }
 
     // The waybar launcher and the deep-link keybinds all reach this:
-    //   qs -p <this dir> ipc call drawer open        -> the grid
-    //   qs -p <this dir> ipc call drawer open mail   -> the mail page
+    //   qs -p <this dir> ipc call drawer toggle       -> the grid
+    //   qs -p <this dir> ipc call drawer open mail    -> the mail page
+    // Quickshell 0.3.1 IPC requires every declared argument to be present,
+    // and a parameter with a JS default registers as QVariant, which IPC
+    // rejects. So the page name cannot be optional: `open` always takes a
+    // page, and the page-less grid is `toggle`.
     IpcHandler {
         target: "drawer"
         function open(page: string) { drawer.show(page); }
-        function toggle(page: string) { drawer.toggle(page); }
+        function toggle() { drawer.toggle(""); }
         function close() { drawer.close(); }
     }
 }
@@ -731,7 +745,7 @@ ShellRoot {
 ```bash
 timeout 8 qs -p desktop 2>&1 | head -20 &
 sleep 3
-qs -p desktop ipc call drawer open
+qs -p desktop ipc call drawer toggle
 sleep 1
 qs -p desktop ipc call drawer close
 wait
@@ -836,7 +850,7 @@ and replace the `Drawer` block with:
 ```bash
 timeout 10 qs -p desktop 2>&1 | head -20 &
 sleep 3
-qs -p desktop ipc call drawer open
+qs -p desktop ipc call drawer toggle
 sleep 5
 wait
 pgrep -cx qs
@@ -2532,7 +2546,7 @@ Reached from a launcher at the left end of waybar.
 
     qs -p ./desktop
 
-    qs -p ./desktop ipc call drawer open        # the grid
+    qs -p ./desktop ipc call drawer toggle      # the grid
     qs -p ./desktop ipc call drawer open mail   # straight to a page
 
 ## The modules