Add Kotlin language support to ADK docs

.github/workflows/kotlin-snippets-pr-check.yaml

@@ -0,0 +1,72 @@
+# Copyright 2026 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: Kotlin Snippets Build on PR
+
+on:
+  # Run on pull requests targeting the main branch.
+  pull_request:
+    branches: [ "main" ]
+
+jobs:
+  # This job builds the Kotlin snippets.
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v6
+      with:
+        # Fetch the entire history to compare branches in the PR.
+        fetch-depth: 0
+
+    - name: Set up JDK 17
+      uses: actions/setup-java@v4
+      with:
+        java-version: '17'
+        distribution: 'temurin'
+
+    - name: Setup Gradle
+      uses: gradle/actions/setup-gradle@v4
+
+    # --- PR-Specific Checks ---
+    # These steps only run for pull request events.
+
+    - name: Find new, un-tested Kotlin files (PR only)
+      if: github.event_name == 'pull_request'
+      run: |
+        echo "Checking for any new Kotlin files that are not in the build script..."
+        ./tools/kotlin-snippets/check_kotlin_snippets.sh
+
+    - name: Get changed Kotlin snippet files (PR only)
+      if: github.event_name == 'pull_request'
+      id: changed-files
+      run: |
+        # This command gets the list of changed .kt files in the snippets directory
+        # between the PR's head and the base branch.
+        CHANGED_FILES=$(git diff --name-only ${{ github.event.pull_request.base.sha }} ${{ github.event.pull_request.head.sha }} -- 'examples/kotlin/snippets/**/*.kt' | xargs)
+        echo "changed_files=${CHANGED_FILES}" >> $GITHUB_OUTPUT
+        echo "Detected changes in: ${CHANGED_FILES}"
+
+    - name: Build changed Kotlin snippets (PR only)
+      if: github.event_name == 'pull_request' && steps.changed-files.outputs.changed_files != ''
+      run: |
+        echo "Building only the changed Kotlin files..."
+        ./tools/kotlin-snippets/runner.sh build ${{ steps.changed-files.outputs.changed_files }}
+
+    - name: Lint changed Kotlin snippets (PR only)
+      if: github.event_name == 'pull_request' && steps.changed-files.outputs.changed_files != ''
+      run: |
+        echo "Linting only the changed Kotlin files..."
+        ./tools/kotlin-snippets/runner.sh lint ${{ steps.changed-files.outputs.changed_files }}

.lycheeignore

@@ -2,6 +2,11 @@
 # Add regular expressions (one per line) for URLs to exclude from checking.
 # See: https://github.com/lycheeverse/lychee-action
 
+# Rate limits automated requests
+^https://www\.gnu\.org/
+^https://www\.markifact\.com
+^https?://x\.com/
+
 # Google Cloud Console (requires authentication, returns HTTP/2 errors)
 ^https://console\.(cloud\.google|developers\.google)\.com
 
@@ -10,7 +15,3 @@
 
 # Requires authentication
 ^https://postman\.postman\.co/settings/me/
-
-# Rate limits automated requests
-^https://www\.gnu\.org/
-^https://www\.markifact\.com

README.md

@@ -4,7 +4,8 @@
 [![PyPI](https://img.shields.io/pypi/v/google-adk)](https://pypi.org/project/google-adk/)
 [![NPM Version](https://img.shields.io/npm/v/@google/adk)](https://www.npmjs.com/package/@google/adk)
 [![Go Doc](https://img.shields.io/badge/Go%20Package-Doc-blue.svg)](https://pkg.go.dev/google.golang.org/adk)
-[![Maven Central](https://img.shields.io/maven-central/v/com.google.adk/google-adk)](https://search.maven.org/artifact/com.google.adk/google-adk)
+[![Maven Central Java](https://img.shields.io/maven-central/v/com.google.adk/google-adk)](https://search.maven.org/artifact/com.google.adk/google-adk)
+[![Maven Central Kotlin](https://img.shields.io/maven-central/v/com.google.adk/google-adk-kotlin-core)](https://search.maven.org/artifact/com.google.adk/google-adk-kotlin-core)
 
 <html>
   <h2 align="center">
@@ -55,6 +56,8 @@ You can use Agent Development Kit (ADK) with your preferred language:
 
 - **[Get started with ADK Java](https://adk.dev/get-started/java/)**
 
+- **[Get started with ADK Kotlin](https://adk.dev/get-started/kotlin/)**
+
 ## 📚 Documentation
 
 Explore the full documentation for detailed guides on building, evaluating, and

docs/_includes/homepage/_hero.md

@@ -2,7 +2,7 @@
 <div class="hero-grid">
   <div class="hero-content">
     <h1>Build production agents, <span class="hero-punchline">not prototypes.</span></h1>
-    <p>ADK is the open-source agent development framework that lets you build, debug, and deploy reliable AI agents at enterprise scale. Available in Python, TypeScript, Go, and Java.</p>
+    <p>ADK is the open-source agent development framework that lets you build, debug, and deploy reliable AI agents at enterprise scale. Available in Python, TypeScript, Go, Java, and Kotlin.</p>
     <div class="hero-actions">
       <a href="get-started/" class="btn btn-primary">Start building</a>
       <!-- <a href="skills/" class="btn btn-accent">Agent skills</a> -->
@@ -17,6 +17,7 @@
           <div class="iterm-tab" data-lang="typescript">TypeScript</div>
           <div class="iterm-tab" data-lang="go">Go</div>
           <div class="iterm-tab" data-lang="java">Java</div>
+          <div class="iterm-tab" data-lang="kotlin">Kotlin</div>
         </div>
 <div class="code-content" id="code-python"><pre><span class="kw">from</span> google.adk <span class="kw">import</span> <span class="fn">Agent</span>
 <span class="kw">from</span> google.adk.tools <span class="kw">import</span> google_search
@@ -39,16 +40,15 @@ agent = <span class="fn">Agent</span>(
 
 </pre></div>
 
-<div class="code-content" id="code-go" style="display:none"><pre><span class="kw">import</span> <span class="str">"google.golang.org/adk/agent"</span>
+<div class="code-content" id="code-go" style="display:none"><pre><span class="kw">import</span> <span class="str">"google.golang.org/adk/agent/llmagent"</span>
 
-a := agent.<span class="fn">New</span>(<span class="str">"researcher"</span>,
-    agent.<span class="fn">WithModel</span>(<span class="str">"gemini-flash-latest"</span>),
-    agent.<span class="fn">WithInstruction</span>(<span class="str">"You help users research topics thoroughly."</span>),
-    agent.<span class="fn">WithTools</span>(googleSearch),
-)
-
-
-</pre></div>
+model, _ := gemini.<span class="fn">NewModel</span>(context.<span class="fn">Background</span>(), <span class="str">"gemini-flash-latest"</span>, <span class="kw">nil</span>)
+a, _ := llmagent.<span class="fn">New</span>(llmagent.<span class="fn">Config</span>{
+    Name:        <span class="str">"researcher"</span>,
+    Model:       model,
+    Instruction: <span class="str">"You help users research topics thoroughly."</span>,
+    Tools:       []tool.Tool{geminitool.<span class="fn">GoogleSearch</span>{}},
+})</pre></div>
 
 <div class="code-content" id="code-java" style="display:none"><pre><span class="kw">import</span> com.google.adk.agents.<span class="fn">LlmAgent</span>;
 <span class="kw">import</span> com.google.adk.tools.<span class="fn">GoogleSearchTool</span>;
@@ -60,6 +60,16 @@ a := agent.<span class="fn">New</span>(<span class="str">"researcher"</span>,
     .tools(<span class="kw">new</span> <span class="fn">GoogleSearchTool()</span>)
     .build();</pre></div>
 
+<div class="code-content" id="code-kotlin" style="display:none"><pre><span class="kw">import</span> com.google.adk.kt.agents.<span class="fn">LlmAgent</span>
+<span class="kw">import</span> com.google.adk.kt.tools.<span class="fn">GoogleSearchTool</span>
+
+<span class="kw">val</span> agent = <span class="fn">LlmAgent</span>(
+    name = <span class="str">"researcher"</span>,
+    model = <span class="fn">Gemini</span>(name = <span class="str">"gemini-flash-latest"</span>),
+    instruction = <span class="fn">Instruction</span>(<span class="str">"You help users research topics thoroughly."</span>),
+    tools = listOf(<span class="fn">GoogleSearchTool</span>()),
+)</pre></div>
+
 </div>
       <!-- Install info synced with tabs -->
       <div class="install-info" id="install-python">
@@ -86,6 +96,12 @@ a := agent.<span class="fn">New</span>(<span class="str">"researcher"</span>,
           <button class="copy-btn" data-copy="com.google.adk:google-adk" title="Copy to clipboard">📋</button>
         </div>
       </div>
+      <div class="install-info" id="install-kotlin" style="display:none">
+        <div class="install-cmd">
+          <code>com.google.adk:google-adk-kotlin-core</code>
+          <button class="copy-btn" data-copy="com.google.adk:google-adk-kotlin-core" title="Copy to clipboard">📋</button>
+        </div>
+      </div>
     </div>
   </div>
 </div>

docs/a2a/a2a-extension.md

@@ -1,7 +1,7 @@
 # A2A extension for improved reliability
 
 <div class="language-support-tag">
-  <span class="lst-supported">Supported in ADK</span><span class="lst-python">Python 1.27.0</span>
+  <span class="lst-supported">Supported in ADK</span><span class="lst-python">Python v1.27.0</span>
 </div>
 
 ADK provides an extension for Agent2Agent (A2A) support to improved message and data handling as part of

docs/agents/llm-agents.md

@@ -1,11 +1,7 @@
 # LLM Agent
 
 <div class="language-support-tag">
-  <span class="lst-supported">Supported in ADK</span>
-  <span class="lst-python">Python v0.1.0</span>
-  <span class="lst-typescript">Typescript v0.2.0</span>
-  <span class="lst-go">Go v0.1.0</span>
-  <span class="lst-java">Java v0.1.0</span>
+  <span class="lst-supported">Supported in ADK</span><span class="lst-python">Python v0.1.0</span><span class="lst-typescript">Typescript v0.2.0</span><span class="lst-go">Go v0.1.0</span><span class="lst-java">Java v0.1.0</span><span class="lst-kotlin">Kotlin v0.1.0</span>
 </div>
 
 The `LlmAgent` (often aliased simply as `Agent`) is a core component in ADK,
@@ -88,6 +84,12 @@ First, you need to establish what the agent *is* and what it's *for*.
             .build();
     ```
 
+=== "Kotlin"
+
+    ```kotlin
+    --8<-- "examples/kotlin/snippets/agents/llm-agent/CapitalAgent.kt:identity"
+    ```
+
 ## Guiding the Agent: Instructions (`instruction`)
 
 The `instruction` parameter is arguably the most critical for shaping an
@@ -183,6 +185,12 @@ tells the agent:
             .build();
     ```
 
+=== "Kotlin"
+
+    ```kotlin
+    --8<-- "examples/kotlin/snippets/agents/llm-agent/CapitalAgent.kt:instruction"
+    ```
+
 *(Note: For instructions that apply to *all* agents in a system, consider using
 `global_instruction` on the root agent, detailed further in the
 [Multi-Agents](multi-agents.md) section.)*
@@ -194,7 +202,7 @@ reasoning. They allow the agent to interact with the outside world, perform
 calculations, fetch real-time data, or execute specific actions.
 
 * **`tools` (Optional):** Provide a list of tools the agent can use. Each item in the list can be:
-    * A native function or method (wrapped as a `FunctionTool`). Python ADK automatically wraps the native function into a `FunctionTool` whereas, you must explicitly wrap your Java methods using `FunctionTool.create(...)`
+    * A native function or method (wrapped as a `FunctionTool`). Python ADK automatically wraps the native function into a `FunctionTool` whereas, you must explicitly wrap your Java methods using `FunctionTool.create(...)`. In Kotlin, you can use the `@Tool` annotation to automatically generate a `FunctionTool` at compile-time.
     * An instance of a class inheriting from `BaseTool`.
     * An instance of another agent (`AgentTool`, enabling agent-to-agent delegation - see [Multi-Agents](multi-agents.md)).
 
@@ -302,6 +310,15 @@ on the conversation and its instructions.
             .build();
     ```
 
+=== "Kotlin"
+
+    ```kotlin
+    --8<-- "examples/kotlin/snippets/agents/llm-agent/CapitalAgent.kt:tool_definition"
+
+    // Add the tool to the agent
+    --8<-- "examples/kotlin/snippets/agents/llm-agent/CapitalAgent.kt:tool_usage"
+    ```
+
 Learn more about Tools in [Custom Tools](/tools-custom/).
 
 ## Advanced Configuration & Control
@@ -373,6 +390,12 @@ You can adjust how the underlying LLM generates responses using `generate_conten
             .build();
     ```
 
+=== "Kotlin"
+
+    ```kotlin
+    --8<-- "examples/kotlin/snippets/agents/llm-agent/CapitalAgent.kt:gen_config"
+    ```
+
 ### Structuring Data (`input_schema`, `output_schema`, `output_key`)
 
 For scenarios requiring structured data exchange with an `LLM Agent`, the ADK provides mechanisms to define expected input and desired output formats using schema definitions.
@@ -753,6 +776,12 @@ call_agent("If it's raining in New York right now, what is the current temperatu
         --8<-- "examples/java/snippets/src/main/java/agents/LlmAgentExample.java:full_code"
         ```
 
+    === "Kotlin"
+
+        ```kotlin
+        --8<-- "examples/kotlin/snippets/agents/llm-agent/CapitalAgent.kt:full_example"
+        ```
+
 _(This example demonstrates the core concepts. More complex agents might incorporate schemas, context control, planning, etc.)_
 
 ## Related Concepts (Deferred Topics)