diff --git a/.agents/docs/notifications.md b/.agents/docs/notifications.md
new file mode 100644
index 0000000..6777083
--- /dev/null
+++ b/.agents/docs/notifications.md
@@ -0,0 +1,27 @@
+# Operation notifications
+
+Provider requests use the Host `ctx.notifications.show()` service. Source icon/name,
+card interactions, queue, expiry and suppression rules belong to Host.
+Declare `notifications` in injection requirements. Field validation and persistent
+business state stay beside the relevant control or object. Do not introduce a
+custom Toast, page-wide operation error, or raw exception message.
+
+The [Host guide](https://github.com/cordisx/cordisx/blob/3cfe370eb7abf33e16686fbd82659cd441247fbd/.agents/docs/notifications.md)
+owns usage and interaction guidance; the
+[Protocol contract](https://github.com/cordisx/cordisx-protocol/blob/f46dd21e15a949a26f05f89bf11dea339fc60c02/.agents/docs/notifications-v1.md)
+owns the public API. Source merge and package publication are separate stages.
+
+## Development dependencies
+
+`package.json` and `package-lock.json` pin formally merged Host and Protocol
+commits. Install through the repository's normal dependency flow:
+
+```sh
+npm ci
+npm run check
+```
+
+Keep the shared Protocol override so public branded types resolve to one copy.
+A missing notification service requires a supported Host upgrade; do not recreate
+notification UI as an older-Host fallback. The former local candidate SDK archive
+is no longer an installation prerequisite.
diff --git a/.gitignore b/.gitignore
index 1eae0cf..edfe37a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,4 @@
 dist/
 node_modules/
+
+.cache/sdk/
diff --git a/AGENTS.md b/AGENTS.md
index c1cebed..a81460e 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -12,3 +12,16 @@
 - Read the organization
   [CSS ownership and maintenance rule](https://github.com/cordisx/cordisxmono/blob/main/.agents/rules/css.md)
   before changing CSS or a style-bearing DOM contract.
+
+## Operation notifications
+
+Use the public `ctx.notifications.show()` service for operation feedback and
+require `notifications` in plugin injection. Do not create a custom Toast,
+manually positioned alert, or page-wide success/error paragraph. Keep field
+validation and durable business state beside the relevant object. Use stable
+semantic `kind` values, localized safe text, and notification rules owned by Host;
+never expose raw exceptions or notify on every polling attempt.
+See the [Host notification guide](https://github.com/cordisx/cordisx/blob/3cfe370eb7abf33e16686fbd82659cd441247fbd/.agents/docs/notifications.md)
+for the interaction contract and older-Host capability boundary.
+
+Dependency setup: [notification migration](./.agents/docs/notifications.md).
diff --git a/README.md b/README.md
index 1d1f93e..1cb4517 100644
--- a/README.md
+++ b/README.md
@@ -39,3 +39,7 @@ Desktop. The package remains `private`; use the explicit local source distributi
 [HISTORY.md](HISTORY.md) records the filtered owner history from the original
 Host-owned implementation. This repository is licensed under
 [AGPL-3.0-or-later](LICENSE).
+
+## Notification feedback
+
+See [operation notifications and development dependencies](./.agents/docs/notifications.md).
diff --git a/package-lock.json b/package-lock.json
index a296010..4a2def6 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -10,7 +10,7 @@
       "license": "AGPL-3.0-or-later",
       "devDependencies": {
         "@cordisx/eslint-config": "github:cordisx/cordisxmono#c63c2e8c2ba7e11502934a52ad2ce3734e804cdc",
-        "@cordisx/protocol": "github:cordisx/cordisx-protocol#c2f6f8e4bf4a638bf4627c9c567792f2fedbcfd6",
+        "@cordisx/protocol": "github:cordisx/cordisx-protocol#f46dd21e15a949a26f05f89bf11dea339fc60c02",
         "@deepseek-ai/cordis": "4.0.1",
         "@deepseek-ai/schemastery": "3.18.1",
         "@projectwallace/stylelint-plugin": "0.7.0",
@@ -18,7 +18,7 @@
         "@vitejs/plugin-react": "6.1.0",
         "ajv": "8.20.0",
         "ajv-formats": "3.0.1",
-        "cordisx": "github:cordisx/cordisx#152d55aa26527b23c5e70a752fb3f6562e944afc",
+        "cordisx": "github:cordisx/cordisx#3cfe370eb7abf33e16686fbd82659cd441247fbd",
         "dprint": "0.57.1",
         "esbuild": "0.28.2",
         "eslint": "9.39.4",
@@ -129,16 +129,6 @@
         "@keyv/serialize": "^1.1.1"
       }
     },
-    "node_modules/@cordisx/channel": {
-      "version": "0.1.0",
-      "resolved": "git+ssh://git@github.com/cordisx/plugin-channel.git#4cee12e3a92eeed557bc9de8cc4792710918327a",
-      "integrity": "sha512-uErxyAHsoKSQKASW8DZM/V6cQt6rPZ8jjE4vzQ8H1rFGIhuB8mE4Qy8PAnw7Y1sFafMsB+ENVqJDrLD5CwiGTA==",
-      "dev": true,
-      "license": "AGPL-3.0-or-later",
-      "engines": {
-        "node": ">=22.19"
-      }
-    },
     "node_modules/@cordisx/eslint-config": {
       "version": "0.1.0",
       "resolved": "git+ssh://git@github.com/cordisx/cordisxmono.git#c63c2e8c2ba7e11502934a52ad2ce3734e804cdc",
@@ -153,8 +143,8 @@
     },
     "node_modules/@cordisx/protocol": {
       "version": "0.1.0-alpha.0",
-      "resolved": "git+ssh://git@github.com/cordisx/cordisx-protocol.git#c2f6f8e4bf4a638bf4627c9c567792f2fedbcfd6",
-      "integrity": "sha512-m+/bdnP/tx0RbzISwUOfOcRVbjuarHTyNdHuX+IsrAETRmTwBTAhJI8S5Irx/2H+YZUrsU23JcUxMZCfcjFwxQ==",
+      "resolved": "git+ssh://git@github.com/cordisx/cordisx-protocol.git#f46dd21e15a949a26f05f89bf11dea339fc60c02",
+      "integrity": "sha512-o/YzvFs5gkrYsK0vijubLN/go2/oL04sixPz/Ks7N0eMLEHUL7qxD56Yf1ltW5dN9qfBIpgkHuiXgkSgOjj1bw==",
       "dev": true,
       "license": "AGPL-3.0-or-later",
       "engines": {
@@ -2708,10 +2698,12 @@
     "node_modules/cordisx": {
       "name": "cordisx-monorepo",
       "version": "0.1.0-beta.2",
-      "resolved": "git+ssh://git@github.com/cordisx/cordisx.git#152d55aa26527b23c5e70a752fb3f6562e944afc",
-      "integrity": "sha512-xMLYyYDpH1nN22T7jLllh83s+hbvFpfv3h2aR8R2p2DG9+bKCnA1RFfw0W6c/h5QztGWQuIRrx0bg+gadcIbYg==",
+      "resolved": "git+ssh://git@github.com/cordisx/cordisx.git#3cfe370eb7abf33e16686fbd82659cd441247fbd",
+      "integrity": "sha512-k6IhNsliOoWBDU0PuaQJUWO/llUdJAlrcdV9ErjyjSK+kYK0MJzO9UWWSnTc3bJGwLJ/Osv1cNo+tGV7BPwhcA==",
       "bundleDependencies": [
-        "@cordisx/schemastery-ui"
+        "@cordisx/schemastery-ui",
+        "@cordisx/channel",
+        "@cordisx/plugin-cli-proxy-api"
       ],
       "dev": true,
       "license": "AGPL-3.0-or-later",
@@ -2720,7 +2712,8 @@
       ],
       "dependencies": {
         "@cordisx/channel": "github:cordisx/plugin-channel#4cee12e3a92eeed557bc9de8cc4792710918327a",
-        "@cordisx/protocol": "github:cordisx/cordisx-protocol#c2f6f8e4bf4a638bf4627c9c567792f2fedbcfd6",
+        "@cordisx/plugin-cli-proxy-api": "github:cordisx/plugin-cli-proxy-api#1428ee205aab31df2779398cc8491879b303d1d0",
+        "@cordisx/protocol": "github:cordisx/cordisx-protocol#f46dd21e15a949a26f05f89bf11dea339fc60c02",
         "@cordisx/schemastery-ui": "0.1.0-beta.2",
         "@deepseek-ai/cordis": "4.0.1",
         "@deepseek-ai/schemastery": "^3.18.1",
@@ -2774,13 +2767,16 @@
       "name": "cordisx",
       "version": "0.1.0-beta.2",
       "bundleDependencies": [
-        "@cordisx/schemastery-ui"
+        "@cordisx/schemastery-ui",
+        "@cordisx/channel",
+        "@cordisx/plugin-cli-proxy-api"
       ],
       "extraneous": true,
       "license": "AGPL-3.0-or-later",
       "dependencies": {
-        "@cordisx/channel": "github:cordisx/plugin-channel#4cee12e3a92eeed557bc9de8cc4792710918327a",
-        "@cordisx/protocol": "github:cordisx/cordisx-protocol#c2f6f8e4bf4a638bf4627c9c567792f2fedbcfd6",
+        "@cordisx/channel": "0.1.0",
+        "@cordisx/plugin-cli-proxy-api": "0.1.0",
+        "@cordisx/protocol": "github:cordisx/cordisx-protocol#f46dd21e15a949a26f05f89bf11dea339fc60c02",
         "@cordisx/schemastery-ui": "0.1.0-beta.2",
         "@deepseek-ai/cordis": "4.0.1",
         "@deepseek-ai/schemastery": "^3.18.1",
@@ -2821,7 +2817,6 @@
       },
       "devDependencies": {
         "@cordisx/channel-runtime": "file:../channel-runtime",
-        "@cordisx/protocol": "github:cordisx/cordisx-protocol#c2f6f8e4bf4a638bf4627c9c567792f2fedbcfd6",
         "@types/node": "^22.18.1",
         "@types/react": "19.2.18",
         "@types/react-dom": "19.2.5",
diff --git a/package.json b/package.json
index 7aec840..828c822 100644
--- a/package.json
+++ b/package.json
@@ -38,13 +38,13 @@
   },
   "devDependencies": {
     "@cordisx/eslint-config": "github:cordisx/cordisxmono#c63c2e8c2ba7e11502934a52ad2ce3734e804cdc",
-    "@cordisx/protocol": "github:cordisx/cordisx-protocol#c2f6f8e4bf4a638bf4627c9c567792f2fedbcfd6",
+    "@cordisx/protocol": "github:cordisx/cordisx-protocol#f46dd21e15a949a26f05f89bf11dea339fc60c02",
     "@deepseek-ai/cordis": "4.0.1",
     "@deepseek-ai/schemastery": "3.18.1",
     "@projectwallace/stylelint-plugin": "0.7.0",
     "@typescript-eslint/parser": "8.69.0",
     "@vitejs/plugin-react": "6.1.0",
-    "cordisx": "github:cordisx/cordisx#152d55aa26527b23c5e70a752fb3f6562e944afc",
+    "cordisx": "github:cordisx/cordisx#3cfe370eb7abf33e16686fbd82659cd441247fbd",
     "dprint": "0.57.1",
     "eslint": "9.39.4",
     "stylelint": "17.15.0",
@@ -64,5 +64,8 @@
   "bugs": {
     "url": "https://github.com/cordisx/plugin-cli-proxy-api/issues"
   },
-  "homepage": "https://github.com/cordisx/plugin-cli-proxy-api#readme"
+  "homepage": "https://github.com/cordisx/plugin-cli-proxy-api#readme",
+  "overrides": {
+    "@cordisx/protocol": "$@cordisx/protocol"
+  }
 }
diff --git a/src/index.ts b/src/index.ts
index 6569d2c..e48642e 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -16,7 +16,7 @@ import { createProviderFleetPage } from './provider-fleet-page.js'
 import { CLI_PROXY_ICON } from './icon.js'
 
 export const name = 'cli-proxy-api'
-export const inject = ['i18n', 'slots', 'pages', 'routes', 'platform']
+export const inject = ['i18n', 'slots', 'pages', 'routes', 'platform', 'notifications']
 export const icon = CLI_PROXY_ICON
 
 const capabilities = [
@@ -76,7 +76,7 @@ interface Messages {
   'state.empty': undefined
   'state.no-models': undefined
   'state.select-session': undefined
-  'state.error': { readonly message: string }
+  'state.error': undefined
   'session.provider': { readonly provider: string }
   'session.model': { readonly model: string }
   'permission.models.read': undefined
@@ -185,7 +185,7 @@ export function apply(ctx: Context, config: Config = Config({})): void {
       'state.empty': 'No matching sessions.',
       'state.no-models': 'No provider models are available.',
       'state.select-session': 'Select a provider session to inspect its content.',
-      'state.error': 'Provider request failed: {message}',
+      'state.error': 'Provider request failed. Check the connection and try again.',
       'session.provider': 'Provider {provider}',
       'session.model': 'Model {model}',
       'permission.models.read': 'List models from configured external providers',
@@ -230,7 +230,7 @@ export function apply(ctx: Context, config: Config = Config({})): void {
       'state.empty': '没有匹配的会话。',
       'state.no-models': '没有可用的 Provider 模型。',
       'state.select-session': '选择一个 Provider 会话以查看内容。',
-      'state.error': 'Provider 请求失败：{message}',
+      'state.error': 'Provider 请求失败，请检查连接后重试',
       'session.provider': 'Provider {provider}',
       'session.model': '模型 {model}',
       'permission.models.read': '读取已配置外部 Provider 的模型',
diff --git a/src/provider-fleet-page.tsx b/src/provider-fleet-page.tsx
index 5b0137a..a708607 100644
--- a/src/provider-fleet-page.tsx
+++ b/src/provider-fleet-page.tsx
@@ -37,7 +37,7 @@ interface Messages {
   'state.empty': undefined
   'state.no-models': undefined
   'state.select-session': undefined
-  'state.error': { readonly message: string }
+  'state.error': undefined
   'session.provider': { readonly provider: string }
   'session.model': { readonly model: string }
 }
@@ -78,8 +78,10 @@ export function createProviderFleetPage(ctx: Context, config: Config) {
     const [steer, setSteer] = useState('')
     const [status, setStatus] = useState('')
 
-    const showError = (error: { readonly message: string }) =>
-      setStatus(props.t('state.error', { message: error.message }))
+    const showError = (_error: { readonly message: string }) => {
+      setStatus('')
+      ctx.notifications.show({ kind: 'provider.request-failed', type: 'error', message: props.t('state.error') })
+    }
     const providerIds = provider === ''
       ? configuredProviders ?? [...new Set(models.map(item => item.ref.providerId))].sort()
       : [provider]
diff --git a/test/manifest.mjs b/test/manifest.mjs
index 5d20a80..d2f37d8 100644
--- a/test/manifest.mjs
+++ b/test/manifest.mjs
@@ -42,7 +42,7 @@ test('exports the CLIProxy renderer manifest through public Host contracts', ()
       'turns.control',
     ],
   )
-  assert.deepEqual(plugin.inject, ['i18n', 'slots', 'pages', 'routes', 'platform'])
+  assert.deepEqual(plugin.inject, ['i18n', 'slots', 'pages', 'routes', 'platform', 'notifications'])
 })
 
 test('registers one public page, route, and navigation contribution', () => {