Update skills (2026-09-07 11:38)

.claude-plugin/marketplace.json

@@ -17,6 +17,7 @@
         "./build-system/agp/agp-9-upgrade",
         "./camera/camerax",
         "./device-ai/appfunctions",
+        "./device-ai/ml-kit-genai-prompt-api",
         "./devtools/android-cli",
         "./identity/restore-credentials",
         "./identity/verified-email",
@@ -25,6 +26,7 @@
         "./jetpack-compose/theming/styles",
         "./media/media3-cast-integration",
         "./navigation/navigation-3",
+        "./navigation/navigation-event",
         "./performance/r8-analyzer",
         "./play/engage-sdk-integration",
         "./play/play-billing-library-version-upgrade",

.codex-plugin/plugin.json

@@ -30,6 +30,11 @@
         "path": "./device-ai/appfunctions"
       }
     },
+    {
+      "source": {
+        "path": "./device-ai/ml-kit-genai-prompt-api"
+      }
+    },
     {
       "source": {
         "path": "./devtools/android-cli"
@@ -70,6 +75,11 @@
         "path": "./navigation/navigation-3"
       }
     },
+    {
+      "source": {
+        "path": "./navigation/navigation-event"
+      }
+    },
     {
       "source": {
         "path": "./performance/r8-analyzer"

device-ai/ml-kit-genai-prompt-api/SKILL.md

@@ -0,0 +1,121 @@
+---
+name: ml-kit-genai-prompt-api
+description: Analyzes Android codebases to implement ML Kit GenAI Prompt API. Use
+  this skill to send natural language requests on-device to Gemini Nano, use structured
+  output with Prompt API, implement prefix caching, optimize the current prompt, or
+  apply best practices."
+license: Complete terms in LICENSE.txt
+metadata:
+  author: Google LLC
+  last-updated: '2026-09-03'
+  keywords:
+  - ML Kit
+  - Prompt API
+  - Structured Output
+  - Prefix Caching
+  - Gemini Nano
+---
+
+This skill provides step-by-step guidance for integrating and optimizing the ML
+Kit GenAI Prompt API in Android apps.
+
+## Prerequisites
+
+- Android API level must be 26 or higher. If `minSdk` is below 26, update it to 26.
+- Add the ML Kit GenAI Prompt API dependency (`com.google.mlkit:genai-prompt`) to the app-level `build.gradle` file, with version at least `1.0.0-beta4`.
+- If `com.google.mlkit:genai-schema-compiler` dependency is used and KSP plugin version is below 2.3.6, update it to 2.3.6.
+
+## Detailed steps
+
+### 1. Prompt optimization
+
+To optimize prompts for use with the ML Kit Prompt API, follow the
+[prompt optimization guide](https://developer.android.com/agents/skills/device-ai/prompt-api/references/prompt-optimization).
+
+### 2. Prefix caching optimization
+
+If the prompt is more than 200 words, implement the [prefix caching API](https://developer.android.com/agents/skills/device-ai/prompt-api/references/prefix-caching).
+
+### 3. Lifecycle and best practices
+
+- The model must be fully downloaded and available before calling the first inference. Follow the guide on [implementing a generative model](https://developer.android.com/agents/skills/device-ai/prompt-api/references/get-started) to check that the `FeatureStatus` of a model is `AVAILABLE` before making an inference.
+- Release ML Kit instances by calling `close()` when an `Activity`,
+  `Fragment`, or `ViewModel` is destroyed. Example:
+
+
+  ```kotlin
+  // Instantiating model in activity, fragment, or ViewModel
+      val generativeModel = Generation.getClient()
+
+  // When activity, fragment, or ViewModel is destroyed
+      generativeModel.close()
+  ```
+
+  <br />
+
+### 4. Structured output
+
+When implementing or refactoring a prompt to use structured output, follow
+these rules:
+
+1. **Check for API availability:** Verify Structured Output feature is available on the device with `isStructuredOutputFeatureAvailable()` before using it. Refer to the [Structured Output API guide](https://developer.android.com/agents/skills/device-ai/prompt-api/references/structured-output) for full instructions.
+2. **Return type:** Return the `@Generable` typed object from the function
+   signature instead of a `String` or JSON string.
+
+   For example:
+
+       fun parseEmail(email: String): String {
+           ... 
+       }
+
+   should be refactored to:
+
+       fun parseEmail(email: String): ParsedEmail? {
+           ...
+       }
+
+3. **Example:**
+
+   This is the example code before refactoring:
+
+
+   ```kotlin
+   suspend fun parseEmail(email: String): String {
+       val parseEmailPrompt = "Parse this email and return the sender, title, and short summary of the email less than 10 words: "
+
+       val parsedEmail = generativeModel.generateContent(parseEmailPrompt + email)
+
+       return parsedEmail.candidates[0].text
+   }
+   ```
+
+   <br />
+
+   This is the example code after using Structured Output API:
+
+
+   ```kotlin
+   @Generable
+   data class ParsedEmail(
+       @Guide(description = "Sender of the email")
+       var sender: String = "",
+
+       @Guide(description = "Title of the email")
+       var title: String = "",
+
+       @Guide(description = "Summary of the email less than 10 words")
+       var summary: String = ""
+   )
+
+   suspend fun parseEmail(email: String): ParsedEmail? {
+       val parseEmailPrompt =
+           "Parse this email: $email"
+
+       val baseRequest = GenerateContentRequest.Builder(TextPart(parseEmailPrompt)).build()
+       val typedRequest = generateTypedContentRequest(baseRequest, ParsedEmail::class)
+       val typedResponse = generativeModel.generateContent(typedRequest)
+       return typedResponse.candidates[0].response
+   }
+   ```
+
+   <br />