diff --git a/app/components/settings/llm-configurations-panel.tsx b/app/components/settings/llm-configurations-panel.tsx
index cc85200..1e35ae5 100644
--- a/app/components/settings/llm-configurations-panel.tsx
+++ b/app/components/settings/llm-configurations-panel.tsx
@@ -52,6 +52,7 @@ import {
   getUsageSummary,
   listConfigurations,
   REASONING_EFFORTS,
+  saveActiveReasoning,
   updateConfiguration,
   type CatalogEntry,
   type LlmConfiguration,
@@ -134,6 +135,10 @@ export function LlmConfigurationsPanel() {
       baseURL: c.base_url || undefined,
       secretName: c.secret_name || undefined,
     })
+    // Inherit this config's reasoning default. The /ai composer chip
+    // listens for this and updates live; if the operator already
+    // override it via the chip, the next save propagates here.
+    saveActiveReasoning(c.reasoning_effort ?? "off")
     setActive(loadActiveSettings())
   }
 
diff --git a/app/lib/arcadia/llm-configs.ts b/app/lib/arcadia/llm-configs.ts
index 9fd8e14..ac51d1c 100644
--- a/app/lib/arcadia/llm-configs.ts
+++ b/app/lib/arcadia/llm-configs.ts
@@ -198,3 +198,49 @@ export function findSpend(
 ): UsageByModelRow | undefined {
   return rows.find((r) => r.provider === config.provider && r.model === config.model)
 }
+
+// ---------------------------------------------------------------------------
+// Active reasoning_effort (shared between settings panel and /ai composer)
+//
+// Stored under crema.ai.reasoning. Written when the operator stars a config
+// in the settings panel (so the chip on /ai inherits that config's default
+// on next mount) and when the operator cycles the THINK chip on /ai (per-
+// conversation override). Wiped on Clear conversation.
+// ---------------------------------------------------------------------------
+
+const ACTIVE_REASONING_KEY = "crema.ai.reasoning"
+const ACTIVE_REASONING_EVENT = "crema:ai-reasoning-change"
+
+export function loadActiveReasoning(): ReasoningEffort {
+  if (typeof window === "undefined") return "off"
+  const v = localStorage.getItem(ACTIVE_REASONING_KEY) as ReasoningEffort | null
+  return v && REASONING_EFFORTS.includes(v) ? v : "off"
+}
+
+export function saveActiveReasoning(v: ReasoningEffort): void {
+  if (typeof window === "undefined") return
+  if (v === "off") localStorage.removeItem(ACTIVE_REASONING_KEY)
+  else localStorage.setItem(ACTIVE_REASONING_KEY, v)
+  window.dispatchEvent(new CustomEvent(ACTIVE_REASONING_EVENT, { detail: v }))
+}
+
+export function subscribeActiveReasoning(
+  listener: (v: ReasoningEffort) => void,
+): () => void {
+  if (typeof window === "undefined") return () => {}
+  const onChange = (e: Event) => {
+    const detail = (e as CustomEvent<ReasoningEffort>).detail
+    if (detail) listener(detail)
+    else listener(loadActiveReasoning())
+  }
+  // Same-tab via the custom event; cross-tab via the storage event.
+  const onStorage = (e: StorageEvent) => {
+    if (e.key === ACTIVE_REASONING_KEY) listener(loadActiveReasoning())
+  }
+  window.addEventListener(ACTIVE_REASONING_EVENT, onChange)
+  window.addEventListener("storage", onStorage)
+  return () => {
+    window.removeEventListener(ACTIVE_REASONING_EVENT, onChange)
+    window.removeEventListener("storage", onStorage)
+  }
+}
diff --git a/app/routes/ai.tsx b/app/routes/ai.tsx
index 7965a22..4fcc21b 100644
--- a/app/routes/ai.tsx
+++ b/app/routes/ai.tsx
@@ -79,6 +79,12 @@ import {
   runLLMToolCalls,
 } from "~/lib/admin-tools"
 import { ARCADIA_KNOWLEDGE } from "~/lib/arcadia-knowledge"
+import {
+  loadActiveReasoning,
+  saveActiveReasoning,
+  subscribeActiveReasoning,
+  type ReasoningEffort,
+} from "~/lib/arcadia/llm-configs"
 import { formatAdminContextForPrompt } from "~/lib/admin-context"
 import { ConfirmCard } from "~/components/assistant/confirm-card"
 import { renderToolResult } from "~/components/assistant/tool-result-renderers"
@@ -181,21 +187,11 @@ function clearLive() {
 }
 
 /* Per-conversation reasoning override. Cycle order matters — the composer
- * chip walks this array. */
-type ReasoningEffort = "off" | "low" | "medium" | "high" | "max"
+ * chip walks this array. Storage helpers (load/save/subscribe) live in
+ * lib/arcadia/llm-configs.ts so the settings panel and the /ai composer
+ * coordinate via the same crema.ai.reasoning key. */
 const REASONING_LEVELS: ReasoningEffort[] = ["off", "low", "medium", "high", "max"]
-const REASONING_KEY = "crema.ai.reasoning"
 
-function loadReasoning(): ReasoningEffort {
-  if (typeof window === "undefined") return "off"
-  const v = localStorage.getItem(REASONING_KEY) as ReasoningEffort | null
-  return v && REASONING_LEVELS.includes(v) ? v : "off"
-}
-function saveReasoning(v: ReasoningEffort) {
-  if (typeof window === "undefined") return
-  if (v === "off") localStorage.removeItem(REASONING_KEY)
-  else localStorage.setItem(REASONING_KEY, v)
-}
 function withReasoning<T extends Record<string, unknown>>(
   extras: T,
   effort: ReasoningEffort,
@@ -537,7 +533,9 @@ function ChatSurface({
     setMessages([])
     setAgentHistory(new Map())
     setMessageAgents(new Map())
-    setReasoningEffort("off")
+    // Keep reasoningEffort as-is. It's bound to the active config's
+    // default (set when the operator stars a config in Settings) and
+    // resetting it would silently undo their intent on every clear.
   }, [setMessages])
 
   // Auto tool-loop using native function calls. Reads run automatically;
@@ -873,13 +871,23 @@ function ChatSurface({
   // Per-conversation reasoning override. Persists across page reloads via
   // localStorage so the operator's chosen level survives a refresh, but
   // resets when they clear the conversation. "off" = pass nothing through.
+  // Initialize from the shared key (settings panel writes this when the
+  // operator stars a config), persist on change, and live-subscribe so a
+  // star action in another tab/route updates the chip without a refresh.
   const [reasoningEffort, setReasoningEffort] = useState<ReasoningEffort>(
-    () => loadReasoning(),
+    () => loadActiveReasoning(),
   )
   useEffect(() => {
-    saveReasoning(reasoningEffort)
+    saveActiveReasoning(reasoningEffort)
     reasoningEffortRef.current = reasoningEffort
   }, [reasoningEffort])
+  useEffect(() => {
+    return subscribeActiveReasoning((next) => {
+      // Don't loop on our own writes — we already wrote `reasoningEffort`
+      // when it changed. Only pick up writes that disagree with state.
+      setReasoningEffort((cur) => (cur === next ? cur : next))
+    })
+  }, [])
 
   const cycleReasoning = useCallback(() => {
     setReasoningEffort((cur) => {