diff --git a/src/renderer/src/runtime/structured-agent-session-host-capability-scaling.test.tsx b/src/renderer/src/runtime/structured-agent-session-host-capability-scaling.test.tsx
index a41dd2bdd0f..ae75125406b 100644
--- a/src/renderer/src/runtime/structured-agent-session-host-capability-scaling.test.tsx
+++ b/src/renderer/src/runtime/structured-agent-session-host-capability-scaling.test.tsx
@@ -25,6 +25,7 @@ import { AGENT_SESSION_PERMISSION_OWN_RUNTIME_CAPABILITY } from '../../../shared
 import { createCompatibleRuntimeStatusResponse } from './runtime-compatibility-test-fixture'
 import { clearRuntimeCompatibilityCacheForTests } from './runtime-rpc-client'
 import { RuntimeHostStatusOwner } from '../../../shared/runtime-host-status-owner'
+import type { RuntimeEnvironmentStatus } from '../../../shared/runtime-host-status'
 import { useStructuredAgentSessionOwnPermissionState } from './structured-agent-session-host-capability'
 
 const owners: RuntimeHostStatusOwner[] = []
@@ -145,3 +146,53 @@ it.each([10, 100])(
     expect(call).not.toHaveBeenCalled()
   }
 )
+
+it('does not rerender local or other-host consumers when an unrelated host status changes', () => {
+  const unrelated = createCompatibleRuntimeStatusResponse('other')
+  const own = createCompatibleRuntimeStatusResponse('host')
+  if (!unrelated.ok || !own.ok) {
+    throw new Error('expected successful fixture')
+  }
+  const statuses = (otherStatus: typeof unrelated.result | null) =>
+    new Map<string, RuntimeEnvironmentStatus>([
+      ['host', { status: own.result, checkedAt: 1 }],
+      ['other', { status: otherStatus, checkedAt: 1 }]
+    ])
+  useAppStore.setState({ runtimeStatusByEnvironmentId: statuses(null) })
+  let renders = 0
+  const targets = [{ kind: 'local' }, { kind: 'environment', environmentId: 'host' }] as const
+  const views = targets.map((target) =>
+    renderHook(() => {
+      renders += 1
+      return useStructuredAgentSessionOwnPermissionState(target)
+    })
+  )
+  const before = renders
+  for (let flip = 0; flip < 10; flip += 1) {
+    act(() =>
+      useAppStore.setState({
+        runtimeStatusByEnvironmentId: statuses(flip % 2 === 0 ? unrelated.result : null)
+      })
+    )
+  }
+  expect(renders - before).toBe(0)
+  const hostState = views[1].result.current
+  act(() =>
+    useAppStore.setState({
+      runtimeStatusByEnvironmentId: new Map<string, RuntimeEnvironmentStatus>([
+        [
+          'host',
+          {
+            status: {
+              ...own.result,
+              capabilities:
+                hostState === 'supported' ? [] : [AGENT_SESSION_PERMISSION_OWN_RUNTIME_CAPABILITY]
+            },
+            checkedAt: 2
+          }
+        ]
+      ])
+    })
+  )
+  expect(views[1].result.current).toBe(hostState === 'supported' ? 'unsupported' : 'supported')
+})
diff --git a/src/renderer/src/runtime/structured-agent-session-host-capability.ts b/src/renderer/src/runtime/structured-agent-session-host-capability.ts
index 4107600a8e8..99592766aa5 100644
--- a/src/renderer/src/runtime/structured-agent-session-host-capability.ts
+++ b/src/renderer/src/runtime/structured-agent-session-host-capability.ts
@@ -1,5 +1,5 @@
 import { AGENT_SESSION_PERMISSION_OWN_RUNTIME_CAPABILITY } from '../../../shared/agent-session-permission-modes-capability'
-import { useEffect, useMemo, useState, useSyncExternalStore } from 'react'
+import { useEffect, useState, useSyncExternalStore } from 'react'
 import { useAppStore } from '@/store'
 import {
   AGENT_SESSION_CONVERSATION_STOP_RUNTIME_CAPABILITY,
@@ -37,19 +37,19 @@ export function useStructuredAgentSessionOwnPermissionState(
 ): StructuredAgentSessionHostCapabilityState {
   const capability = AGENT_SESSION_PERMISSION_OWN_RUNTIME_CAPABILITY
   const environmentId = target?.kind === 'environment' ? target.environmentId : null
-  const statuses = useAppStore((state) => state.runtimeStatusByEnvironmentId)
-  const remote = useMemo((): StructuredAgentSessionHostCapabilityState => {
+  // Select the verdict, not the map: unrelated host flips must not rerender every chat.
+  const remote = useAppStore((state): StructuredAgentSessionHostCapabilityState => {
     if (environmentId === null) {
       return 'unknown'
     }
-    const entry = statuses.get(environmentId)
+    const entry = state.runtimeStatusByEnvironmentId.get(environmentId)
     const status = isRuntimeHostContactRevoked(entry) ? null : lastVerifiedRuntimeStatus(entry)
     return status
       ? status.capabilities?.includes(capability)
         ? 'supported'
         : 'unsupported'
       : 'unknown'
-  }, [statuses, environmentId, capability])
+  })
   const local = useSyncExternalStore(
     subscribeLocalRuntimeCapabilityObservation,
     () => localCapabilityState(capability),