diff --git a/packages/core/src/agent.ts b/packages/core/src/agent.ts
index 14732fdd752..dd799892326 100644
--- a/packages/core/src/agent.ts
+++ b/packages/core/src/agent.ts
@@ -50,6 +50,24 @@ const layer = Layer.effect(
   Service,
   Effect.gen(function* () {
     const bus = yield* Bus.Service
+    const selectable = (agent: Info | undefined) =>
+      agent && agent.mode !== "subagent" && !agent.hidden ? agent : undefined
+    const selectedDefault = (data: Data) => {
+      const configured = data.default ? selectable(data.agents.get(data.default)) : undefined
+      if (configured) return configured
+      const build = selectable(data.agents.get(ID.make("build")))
+      if (build) return build
+      for (const agent of data.agents.values()) {
+        const fallback = selectable(agent)
+        if (fallback) return fallback
+      }
+    }
+    const list = (data: Data) => {
+      const agents = Array.fromIterable(data.agents.values())
+      const selected = selectedDefault(data)
+      if (!selected) return agents
+      return [selected, ...agents.filter((agent) => agent.id !== selected.id)]
+    }
     const state = State.create<Data, Editor>({
       name: "agent",
       initial: () => ({ agents: new Map() }),
@@ -69,21 +87,8 @@ const layer = Layer.effect(
           editor.agents.delete(id)
         },
       }),
-      notify: () => bus.publish(Agent.Event.Updated, {}).pipe(Effect.asVoid),
+      notify: State.changes(list, () => bus.publish(Agent.Event.Updated, {}).pipe(Effect.asVoid)),
     })
-    const selectable = (agent: Info | undefined) =>
-      agent && agent.mode !== "subagent" && !agent.hidden ? agent : undefined
-    const selectedDefault = () => {
-      const data = state.get()
-      const configured = data.default ? selectable(data.agents.get(data.default)) : undefined
-      if (configured) return configured
-      const build = selectable(data.agents.get(ID.make("build")))
-      if (build) return build
-      for (const agent of data.agents.values()) {
-        const fallback = selectable(agent)
-        if (fallback) return fallback
-      }
-    }
 
     return Service.of({
       transform: state.transform,
@@ -93,21 +98,18 @@ const layer = Layer.effect(
       }),
       resolve: Effect.fnUntraced(function* (id) {
         if (id !== undefined) return state.get().agents.get(ID.make(id))
-        return selectedDefault()
+        return selectedDefault(state.get())
       }),
       select: Effect.fn("Agent.select")(function* (id) {
         if (id !== undefined) {
           const selected = ID.make(id)
           return { id: selected, info: state.get().agents.get(selected) }
         }
-        const info = selectedDefault()
+        const info = selectedDefault(state.get())
         return { id: info?.id ?? defaultID, info }
       }),
       list: Effect.fn("Agent.list")(function* () {
-        const agents = Array.fromIterable(state.get().agents.values())
-        const selected = selectedDefault()
-        if (!selected) return agents
-        return [selected, ...agents.filter((agent) => agent.id !== selected.id)]
+        return list(state.get())
       }),
     })
   }),
diff --git a/packages/core/src/command.ts b/packages/core/src/command.ts
index 8cf1b06bcfb..5678fafbe51 100644
--- a/packages/core/src/command.ts
+++ b/packages/core/src/command.ts
@@ -54,19 +54,22 @@ export const layer = Layer.effect(
   Service,
   Effect.gen(function* () {
     const bus = yield* Bus.Service
+    const info = (definition: Definition) =>
+      Info.make({
+        name: definition.name,
+        description: definition.description,
+      })
     const state = State.create<Map<string, Definition>, Editor>({
       name: "command",
       initial: () => new Map(),
       editor: (editor) => ({
         add: (definition) => editor.set(definition.name, definition),
       }),
-      notify: () => bus.publish(Command.Event.Updated, {}).pipe(Effect.asVoid),
+      notify: State.changes(
+        (commands) => Array.from(commands.values(), info),
+        () => bus.publish(Command.Event.Updated, {}).pipe(Effect.asVoid),
+      ),
     })
-    const info = (definition: Definition) =>
-      Info.make({
-        name: definition.name,
-        description: definition.description,
-      })
 
     return Service.of({
       reload: state.reload,
diff --git a/packages/core/src/integration.ts b/packages/core/src/integration.ts
index 8480e463245..b4ef28467ef 100644
--- a/packages/core/src/integration.ts
+++ b/packages/core/src/integration.ts
@@ -379,7 +379,13 @@ const layer = Layer.effect(
           },
         },
       }),
-      notify: () => bus.publish(Integration.Event.Updated, {}).pipe(Effect.asVoid),
+      notify: State.changes(
+        (data) =>
+          Array.from(data.integrations.values(), (entry) => project(entry, resolveConnections(entry, []))).toSorted(
+            (a, b) => a.name.localeCompare(b.name),
+          ),
+        () => bus.publish(Integration.Event.Updated, {}).pipe(Effect.asVoid),
+      ),
     })
 
     const createCredential = Effect.fnUntraced(function* (input: Parameters<Credential.Interface["create"]>[0]) {
diff --git a/packages/core/src/plugin.ts b/packages/core/src/plugin.ts
index 8ade6826585..e423d11eb2f 100644
--- a/packages/core/src/plugin.ts
+++ b/packages/core/src/plugin.ts
@@ -40,6 +40,10 @@ const layer = Layer.effect(
     const pendingFailures = yield* Queue.unbounded<PendingFailure>()
     let discovered: readonly Failure[] = []
     let inventory: Plugin.Info[] = []
+    const publish = State.changes(
+      (items: readonly Plugin.Info[]) => items,
+      () => bus.publish(Plugin.Event.Updated, {}).pipe(Effect.asVoid),
+    )
     const list = Effect.fn("Plugin.list")(function* () {
       return inventory
     })
@@ -115,10 +119,8 @@ const layer = Layer.effect(
                 if (entry) active.set(definition.id, { ...entry, plugin: definition })
               }
               if (prefix === definitions.length && active.size === definitions.length) {
-                const nextInventory = [...Array.from(active.values()).map(slotInfo), ...failures]
-                if (JSON.stringify(inventory) === JSON.stringify(nextInventory)) return
-                inventory = nextInventory
-                yield* bus.publish(Plugin.Event.Updated, {})
+                inventory = [...Array.from(active.values()).map(slotInfo), ...failures]
+                yield* publish(inventory)
                 return
               }
 
@@ -172,7 +174,7 @@ const layer = Layer.effect(
                   inventory = [...Array.from(active.values()).map(slotInfo), ...failures]
                 }),
               )
-              yield* bus.publish(Plugin.Event.Updated, {})
+              yield* publish(inventory)
             }),
           ),
         (release) => release,
@@ -195,7 +197,7 @@ const layer = Layer.effect(
               // cannot disable a replacement and teardown need not wait for this worker.
               inventory = [...Array.from(active.values()).map(slotInfo), ...discovered]
               const refreshed = yield* State.batch(item.refresh).pipe(Effect.exit)
-              yield* bus.publish(Plugin.Event.Updated, {})
+              yield* publish(inventory)
               if (Exit.isFailure(refreshed))
                 yield* Effect.logWarning("failed to refresh state after disabling plugin", {
                   "plugin.id": item.plugin.id,
diff --git a/packages/core/src/reference.ts b/packages/core/src/reference.ts
index d567abd5f5d..c1bdcb376ef 100644
--- a/packages/core/src/reference.ts
+++ b/packages/core/src/reference.ts
@@ -48,8 +48,8 @@ const layer = Layer.effect(
     const bus = yield* Bus.Service
     const cache = yield* RepositoryCache.Service
     const scope = yield* Scope.Scope
-    const list = (): Info[] =>
-      Array.from(state.get().sources).flatMap(([name, source]) => {
+    const list = (data: Data = state.get()): Info[] =>
+      Array.from(data.sources).flatMap(([name, source]) => {
         const info = {
           name,
           source,
@@ -101,11 +101,12 @@ const layer = Layer.effect(
         list: () => Array.from(editor.sources),
         get: (name) => editor.sources.get(name),
       }),
-      notify: () =>
+      notify: State.changes(list, () =>
         Effect.gen(function* () {
           yield* refresh().pipe(Effect.forkIn(scope))
           yield* bus.publish(Reference.Event.Updated, {})
         }),
+      ),
     })
 
     // Check independently of session activity; the shared cache throttles Git work daily.
diff --git a/packages/core/src/skill.ts b/packages/core/src/skill.ts
index 51cf0bc170a..aedb75d8b70 100644
--- a/packages/core/src/skill.ts
+++ b/packages/core/src/skill.ts
@@ -116,7 +116,10 @@ const layer = Layer.effect(
           editor.skills.delete(ID.make(id))
         },
       }),
-      notify: () => bus.publish(Skill.Event.Updated, {}).pipe(Effect.asVoid),
+      notify: State.changes(
+        (data) => Array.from(data.skills.values()),
+        () => bus.publish(Skill.Event.Updated, {}).pipe(Effect.asVoid),
+      ),
     })
 
     return Service.of({
diff --git a/packages/core/src/state.ts b/packages/core/src/state.ts
index eafee2696e5..2d1690ecec4 100644
--- a/packages/core/src/state.ts
+++ b/packages/core/src/state.ts
@@ -126,6 +126,25 @@ export function reconcile(
   })
 }
 
+/**
+ * Runs `notify` only when the serialized projection of `project(state)` differs from the last
+ * notified value. The first notification always runs so a freshly booted Location announces its
+ * current catalog even when empty.
+ */
+export function changes<State>(
+  project: (state: State) => unknown,
+  notify: (state: State) => Effect.Effect<void>,
+): (state: State) => Effect.Effect<void> {
+  let published: string | undefined
+  return (state) =>
+    Effect.suspend(() => {
+      const next = JSON.stringify(project(state)) ?? ""
+      if (next === published) return Effect.void
+      published = next
+      return notify(state)
+    })
+}
+
 export const inherit = Effect.fnUntraced(function* () {
   const batch = yield* CurrentBatch
   return <A, E, R>(effect: Effect.Effect<A, E, R>) => Effect.provideService(effect, CurrentBatch, batch)
diff --git a/packages/core/src/websearch.ts b/packages/core/src/websearch.ts
index dc37dd45c05..f8f8dd3073b 100644
--- a/packages/core/src/websearch.ts
+++ b/packages/core/src/websearch.ts
@@ -99,6 +99,12 @@ const layer = Layer.effect(
       ),
       Effect.forkScoped({ startImmediately: true }),
     )
+    const providers = (data: Data) =>
+      Array.from(data.providers.values(), (provider) => ({
+        id: provider.id,
+        name: provider.name,
+      })).toSorted((a, b) => a.name.localeCompare(b.name))
+
     const state = State.create<Data, Editor>({
       initial: () => ({ providers: new Map() }),
       editor: (editor) => ({
@@ -108,7 +114,7 @@ const layer = Layer.effect(
           set: (selection) => (editor.selection = selection),
         },
       }),
-      notify: () => bus.publish(WebSearch.Event.Updated, {}).pipe(Effect.asVoid),
+      notify: State.changes(providers, () => bus.publish(WebSearch.Event.Updated, {}).pipe(Effect.asVoid)),
     })
 
     const requireProvider = (providers: Map<ID, ProviderImplementation>, providerID: ID) => {
@@ -162,10 +168,7 @@ const layer = Layer.effect(
       transform: state.transform,
       reload: state.reload,
       providers: Effect.fn("WebSearch.providers")(function* () {
-        return Array.from(state.get().providers.values(), (provider) => ({
-          id: provider.id,
-          name: provider.name,
-        })).toSorted((a, b) => a.name.localeCompare(b.name))
+        return providers(state.get())
       }),
       default: Effect.fn("WebSearch.defaultInfo")(function* () {
         const provider = yield* defaultProvider(yield* selection())
diff --git a/packages/core/test/config/reload.test.ts b/packages/core/test/config/reload.test.ts
index f6acae19fc7..7fd0de8abca 100644
--- a/packages/core/test/config/reload.test.ts
+++ b/packages/core/test/config/reload.test.ts
@@ -8,10 +8,12 @@ import { Command } from "@opencode/core/command"
 import { Config } from "@opencode/core/config"
 import { ConfigAgentPlugin } from "@opencode/core/config/plugin/agent"
 import { ConfigCommandPlugin } from "@opencode/core/config/plugin/command"
+import { ConfigPolicyPlugin } from "@opencode/core/config/plugin/policy"
 import { ConfigProviderPlugin } from "@opencode/core/config/plugin/provider"
 import { ConfigReferencePlugin } from "@opencode/core/config/plugin/reference"
 import { ConfigCompatibilityPlugin } from "@opencode/core/config/plugin/compatibility"
 import { ConfigSkillPlugin } from "@opencode/core/config/plugin/skill"
+import { ConfigWebSearchPlugin } from "@opencode/core/config/plugin/websearch"
 import { Bus } from "@opencode/core/bus"
 import { Integration } from "@opencode/core/integration"
 import { Plugin } from "@opencode/core/plugin"
@@ -20,6 +22,8 @@ import { AppNodeBuilder } from "@opencode/core/effect/app-node-builder"
 import { Provider } from "@opencode/core/provider"
 import { Reference } from "@opencode/core/reference"
 import { Skill } from "@opencode/core/skill"
+import { State } from "@opencode/core/state"
+import { WebSearch } from "@opencode/core/websearch"
 import { ShellSelect } from "@opencode/core/shell/select"
 import { Job } from "@opencode/core/job"
 import { SubagentJob } from "@opencode/core/session/subagent-job"
@@ -323,6 +327,161 @@ describe("config plugin reloads", () => {
       Effect.provideService(Global.Service, Global.Service.of(Global.make())),
     ),
   )
+
+  it.live("publishes catalog updates on boot and real changes but skips unchanged reloads", () =>
+    Effect.gen(function* () {
+      const bus = yield* Bus.Service
+      const integrations = yield* Integration.Service
+      const plugins = yield* Plugin.Service
+      const websearch = yield* WebSearch.Service
+      const baseHost = yield* PluginHost.make(plugins)
+      const test = yield* Config.Test
+      const tracked = new Set<string>([
+        Agent.Event.Updated.type,
+        Command.Event.Updated.type,
+        Skill.Event.Updated.type,
+        Reference.Event.Updated.type,
+        WebSearch.Event.Updated.type,
+        Integration.Event.Updated.type,
+        Credential.Event.Updated.type,
+        Credential.Event.Switched.type,
+      ])
+      const counts = new Map<string, number>()
+      const reloads = { agent: 0, command: 0, skill: 0, reference: 0, websearch: 0, integration: 0 }
+      const count = (type: string) => counts.get(type) ?? 0
+      yield* Effect.acquireRelease(
+        bus.listen((event) =>
+          Effect.sync(() => {
+            if (!tracked.has(event.type)) return
+            counts.set(event.type, count(event.type) + 1)
+          }),
+        ),
+        (unsubscribe) => unsubscribe,
+      )
+      const host: typeof baseHost = {
+        ...baseHost,
+        agent: {
+          ...baseHost.agent,
+          reload: () => baseHost.agent.reload().pipe(Effect.tap(() => Effect.sync(() => void reloads.agent++))),
+        },
+        command: {
+          ...baseHost.command,
+          reload: () => baseHost.command.reload().pipe(Effect.tap(() => Effect.sync(() => void reloads.command++))),
+        },
+        skill: {
+          ...baseHost.skill,
+          reload: () => baseHost.skill.reload().pipe(Effect.tap(() => Effect.sync(() => void reloads.skill++))),
+        },
+        reference: {
+          ...baseHost.reference,
+          reload: () => baseHost.reference.reload().pipe(Effect.tap(() => Effect.sync(() => void reloads.reference++))),
+        },
+        websearch: {
+          ...baseHost.websearch,
+          reload: () => baseHost.websearch.reload().pipe(Effect.tap(() => Effect.sync(() => void reloads.websearch++))),
+        },
+        integration: {
+          ...baseHost.integration,
+          reload: () =>
+            baseHost.integration.reload().pipe(Effect.tap(() => Effect.sync(() => void reloads.integration++))),
+        },
+      }
+
+      let providerName = "First search"
+      yield* State.batch(
+        Effect.gen(function* () {
+          yield* websearch.transform((editor) =>
+            editor.add({ id: WebSearch.ID.make("search"), name: providerName, execute: () => Effect.succeed([]) }),
+          )
+          yield* ConfigAgentPlugin.Plugin.effect(host)
+          yield* ConfigCommandPlugin.Plugin.effect(host)
+          yield* ConfigSkillPlugin.Plugin.effect(host)
+          yield* ConfigPolicyPlugin.Plugin.effect(host)
+          yield* ConfigReferencePlugin.Plugin.effect(host)
+          yield* ConfigWebSearchPlugin.Plugin.effect(host)
+          yield* ConfigProviderPlugin.Plugin.effect(host)
+        }),
+      )
+      expect(Object.fromEntries(counts)).toEqual({
+        [Agent.Event.Updated.type]: 1,
+        [Command.Event.Updated.type]: 1,
+        [Skill.Event.Updated.type]: 1,
+        [Reference.Event.Updated.type]: 1,
+        [WebSearch.Event.Updated.type]: 1,
+        [Integration.Event.Updated.type]: 1,
+      })
+
+      counts.clear()
+      yield* Effect.yieldNow
+      yield* bus.publish(Event.Updated, {})
+      yield* waitUntil(
+        Effect.sync(
+          () =>
+            reloads.agent === 1 &&
+            reloads.command === 1 &&
+            reloads.skill === 2 &&
+            reloads.reference === 1 &&
+            reloads.websearch === 1 &&
+            reloads.integration === 1,
+        ),
+      )
+      expect(Object.fromEntries(counts)).toEqual({})
+
+      yield* integrations.connection.key({
+        integrationID: Integration.ID.make("first"),
+        key: "sk-test",
+        label: "Work",
+      })
+      const connected = yield* integrations.get(Integration.ID.make("first"))
+      expect(connected?.connections).toMatchObject([{ type: "credential", label: "Work", method: "key" }])
+      expect(Object.fromEntries(counts)).toEqual({
+        [Credential.Event.Updated.type]: 1,
+        [Credential.Event.Switched.type]: 1,
+      })
+
+      counts.clear()
+      yield* bus.publish(Event.Updated, {})
+      yield* waitUntil(
+        Effect.sync(
+          () =>
+            reloads.agent === 2 &&
+            reloads.command === 2 &&
+            reloads.skill === 4 &&
+            reloads.reference === 2 &&
+            reloads.websearch === 2 &&
+            reloads.integration === 2,
+        ),
+      )
+      expect(Object.fromEntries(counts)).toEqual({})
+
+      yield* test.setEntries([config("second")])
+      providerName = "Second search"
+      yield* host.websearch.reload()
+      yield* bus.publish(Event.Updated, {})
+      yield* waitUntil(
+        Effect.sync(
+          () =>
+            reloads.agent === 3 &&
+            reloads.command === 3 &&
+            reloads.skill === 6 &&
+            reloads.reference === 3 &&
+            reloads.websearch === 4 &&
+            reloads.integration === 3,
+        ),
+      )
+      expect(Object.fromEntries(counts)).toEqual({
+        [Agent.Event.Updated.type]: 1,
+        [Command.Event.Updated.type]: 1,
+        [Skill.Event.Updated.type]: 1,
+        [Reference.Event.Updated.type]: 1,
+        [WebSearch.Event.Updated.type]: 1,
+        [Integration.Event.Updated.type]: 1,
+      })
+    }).pipe(
+      Effect.provide(Config.testLayer([config("first")])),
+      Effect.provideService(Global.Service, Global.Service.of(Global.make())),
+    ),
+  )
 })
 
 function liveConfig(directory: string, native?: Watcher.NativeInterface, options: Config.Options = { global: false }) {
diff --git a/packages/core/test/config/skill.test.ts b/packages/core/test/config/skill.test.ts
index 6d0882f0caf..66d0ef6c16e 100644
--- a/packages/core/test/config/skill.test.ts
+++ b/packages/core/test/config/skill.test.ts
@@ -416,7 +416,8 @@ describe("ConfigSkillPlugin.Plugin", () => {
           expect(yield* watcher.subscriptions()).toEqual([{ path: path.join(tmp.path, "generated"), type: "file" }])
 
           yield* Effect.promise(() => fs.mkdir(path.join(tmp.path, "generated")))
-          yield* emitAndWait({ type: "create", path: path.join(tmp.path, "generated") })
+          yield* watcher.emit({ type: "create", path: path.join(tmp.path, "generated") })
+          while ((yield* watcher.subscriptions()).at(-1)?.path !== source) yield* Effect.sleep("10 millis")
           yield* Effect.promise(async () => {
             await fs.mkdir(path.join(source, "deploy"), { recursive: true })
             await write(source, "deploy", "Deploy")
diff --git a/packages/core/test/state.test.ts b/packages/core/test/state.test.ts
index 1a73acf2891..0fc0f325c63 100644
--- a/packages/core/test/state.test.ts
+++ b/packages/core/test/state.test.ts
@@ -202,6 +202,37 @@ describe("State", () => {
       expect(finalized).toBe(2)
     }),
   )
+
+  it.effect("publishes the initial projection and skips unchanged reloads", () =>
+    Effect.gen(function* () {
+      let notifications = 0
+      let label = "first"
+      const state = State.create({
+        initial: () => ({ items: [] as { name: string; execute: () => void }[] }),
+        editor: (editor) => ({
+          add: (name: string) => editor.items.push({ name, execute: () => {} }),
+        }),
+        notify: State.changes(
+          (data) => data.items.map((item) => ({ name: item.name })),
+          () => Effect.sync(() => void notifications++),
+        ),
+      })
+
+      yield* state.transform(() => {})
+      expect(notifications).toBe(1)
+      yield* state.reload()
+      expect(notifications).toBe(1)
+
+      yield* state.transform((editor) => editor.add(label))
+      expect(notifications).toBe(2)
+      yield* state.reload()
+      expect(notifications).toBe(2)
+
+      label = "second"
+      yield* state.reload()
+      expect(notifications).toBe(3)
+    }),
+  )
 })
 
 describe("State rebuild", () => {