diff --git a/frontend/src/components/Chat/ChatPanel.tsx b/frontend/src/components/Chat/ChatPanel.tsx
index bca0609..fcfe8ed 100644
--- a/frontend/src/components/Chat/ChatPanel.tsx
+++ b/frontend/src/components/Chat/ChatPanel.tsx
@@ -304,7 +304,7 @@ export function ChatPanel() {
   return (
     <SidePanel
       open={open}
-      label="Assistant"
+      label={controlling ? "Control" : "Assistant"}
       testId="chat-panel"
       bodyKey="chat"
       fixed
diff --git a/frontend/src/components/Common/DashboardMosaic.tsx b/frontend/src/components/Common/DashboardMosaic.tsx
index c3bd5bd..b536b1e 100644
--- a/frontend/src/components/Common/DashboardMosaic.tsx
+++ b/frontend/src/components/Common/DashboardMosaic.tsx
@@ -8,10 +8,14 @@ import { cn } from "@/lib/utils"
 /** Columns a dashboard is cut into when its document does not say. */
 const DEFAULT_COLUMNS = 12
 
-/** Widgets that draw a shape, and widgets that are controls. The rest read out. */
+/**
+ * Widgets that draw a shape, and widgets that are controls. The rest read out.
+ * `INPUT` mirrors `INPUT_WIDGETS`, copied so this list does not load every widget.
+ */
 const GRAPHIC = new Set(["chart", "forecast", "bar", "gauge"])
 const INPUT = new Set([
   "button",
+  "buttons",
   "switch",
   "slider",
   "input",
diff --git a/frontend/src/components/Common/UplotChart.tsx b/frontend/src/components/Common/UplotChart.tsx
index 044ed5d..74b334f 100644
--- a/frontend/src/components/Common/UplotChart.tsx
+++ b/frontend/src/components/Common/UplotChart.tsx
@@ -309,7 +309,7 @@ export function UplotChart({
   // while a new reading only sets its data. The unit, the fixed range and the
   // axis title are part of it — all are baked into the axes at build time —
   // and so are the line shape and the palette, which the series close over.
-  const key = `${labels.join(" ")}|${unit ?? ""}|${yRange?.join(",") ?? ""}|${yLabel ?? ""}|${smooth}|${palette?.join("") ?? ""}|${xTime}`
+  const key = `${JSON.stringify(labels)}|${unit ?? ""}|${yRange?.join(",") ?? ""}|${yLabel ?? ""}|${smooth}|${palette?.join("") ?? ""}|${xTime}`
   // uPlot leaves its axes half-initialised while the scales have no range, and
   // a resize in that window (a card still settling, say) draws them anyway and
   // throws. Waiting for the first reading avoids the state altogether.
diff --git a/frontend/src/components/Flow/NodePanel.tsx b/frontend/src/components/Flow/NodePanel.tsx
index e2147a4..7537ca4 100644
--- a/frontend/src/components/Flow/NodePanel.tsx
+++ b/frontend/src/components/Flow/NodePanel.tsx
@@ -1287,6 +1287,7 @@ function ParamsForm({
       description?: string
       default?: unknown
       enum?: unknown[]
+      anyOf?: { type?: string }[]
       "x-secret"?: boolean
     }
   >
@@ -1326,8 +1327,13 @@ function ParamsForm({
 
         const value = params[key] ?? property.default ?? ""
         const label = property.title ?? key
+        // An optional setting (`float | None`) has its type inside `anyOf`.
+        const options = property.anyOf?.map((option) => option.type) ?? []
+        const kind =
+          property.type ?? options.find((option) => option !== "null")
+        const nullable = options.includes("null")
 
-        if (property.type === "boolean") {
+        if (kind === "boolean") {
           return (
             <div key={key} className="flex items-center justify-between gap-2">
               <Label htmlFor={`param-${key}`} className="text-sm font-normal">
@@ -1384,8 +1390,8 @@ function ParamsForm({
         }
 
         if (
-          property.type === "object" ||
-          property.type === "array" ||
+          kind === "object" ||
+          kind === "array" ||
           (value !== null && typeof value === "object")
         ) {
           // An inject's per-port payloads are the fields drawn above.
@@ -1400,7 +1406,7 @@ function ParamsForm({
                 value={
                   params[key] ??
                   property.default ??
-                  (property.type === "array" ? [] : {})
+                  (kind === "array" ? [] : {})
                 }
                 label={label}
                 onChange={(next) => set(key, next)}
@@ -1440,8 +1446,7 @@ function ParamsForm({
           )
         }
 
-        const numeric =
-          property.type === "integer" || property.type === "number"
+        const numeric = kind === "integer" || kind === "number"
         return (
           <div key={key} className="grid gap-1.5">
             <FieldLabel htmlFor={`param-${key}`} help={property.description}>
@@ -1454,7 +1459,16 @@ function ParamsForm({
               value={String(value)}
               suggestions={suggestions[key] ?? []}
               empty="Nothing like that in use yet."
-              onChange={(next) => set(key, numeric ? Number(next) : next)}
+              onChange={(next) =>
+                set(
+                  key,
+                  nullable && next === ""
+                    ? null
+                    : numeric
+                      ? Number(next)
+                      : next,
+                )
+              }
             />
             {key === "cron" ? (
               <CronHelp
diff --git a/frontend/src/routes/_layout.tsx b/frontend/src/routes/_layout.tsx
index b911f5c..2bdec53 100644
--- a/frontend/src/routes/_layout.tsx
+++ b/frontend/src/routes/_layout.tsx
@@ -54,7 +54,7 @@ function Layout() {
             away rather than behind the sidebar sheet: Home's conversation
             with the house, the assistant anywhere else. */}
         <header className="sticky top-0 z-10 flex h-16 shrink-0 items-center gap-2 px-4 md:hidden">
-          <SidebarTrigger className="-ml-1 text-muted-foreground" />
+          <SidebarTrigger className="-ml-3 size-11 text-muted-foreground" />
           <div className="-mr-3 ml-auto flex items-center">
             <ChatTrigger tab={home ? "control" : "build"} />
           </div>
diff --git a/frontend/src/utils.ts b/frontend/src/utils.ts
index c203d04..d855b28 100644
--- a/frontend/src/utils.ts
+++ b/frontend/src/utils.ts
@@ -3,7 +3,7 @@ import type { ApiError } from "./client"
 import { offlineDetail } from "./lib/connectionStore"
 import { ago } from "./lib/utils"
 
-function extractErrorMessage(err: ApiError): string {
+export function extractErrorMessage(err: ApiError): string {
   // An unreachable instance is not a rejected action: say plainly that
   // nothing was delivered, so nobody is left wondering whether it half-landed.
   const offline = offlineDetail(err)
@@ -21,7 +21,9 @@ function extractErrorMessage(err: ApiError): string {
   if (Array.isArray(errDetail) && errDetail.length > 0) {
     return errDetail[0].msg
   }
-  return errDetail || "Something went wrong."
+  // A conflict carries `{message, current_version}` rather than a string.
+  if (typeof errDetail?.message === "string") return errDetail.message
+  return (typeof errDetail === "string" && errDetail) || "Something went wrong."
 }
 
 export const handleError = function (