From c415cb8b987a8e99c951630308116f16733724a1 Mon Sep 17 00:00:00 2001
From: Ed Burns <edburns@microsoft.com>
Date: Thu, 28 May 2026 15:34:24 -0700
Subject: [PATCH 1/3] backport https://github.com/github/copilot-sdk/pull/1483

---
 .github/actions/test-report/action.yml        |  10 +-
 .github/workflows/build-test.yml              |  82 +++++---
 README.md                                     |  80 +++----
 jbang-example.java                            |   2 +-
 pom.xml                                       | 129 +++++++++++-
 scripts/compare-standalone-to-monorepo.sh     |  52 ++++-
 .../com/github/copilot/CopilotClient.java     | 197 +++++++++++++-----
 .../com/github/copilot/CopilotSession.java    |  39 +++-
 .../copilot/InternalExecutorProvider.java     |  60 ++++++
 .../github/copilot/SessionRequestBuilder.java |  18 +-
 .../copilot/rpc/CopilotClientOptions.java     |  21 +-
 .../copilot/rpc/CreateSessionRequest.java     |  88 +++++++-
 .../copilot/rpc/LargeToolOutputConfig.java    |  91 ++++++++
 .../github/copilot/rpc/MessageOptions.java    |  26 +++
 .../copilot/rpc/ResumeSessionConfig.java      | 144 ++++++++++++-
 .../copilot/rpc/ResumeSessionRequest.java     |  88 +++++++-
 .../copilot/rpc/SendMessageRequest.java       |  18 ++
 .../com/github/copilot/rpc/SessionConfig.java | 162 +++++++++++++-
 .../copilot/rpc/SessionUiCapabilities.java    |  40 ++++
 .../copilot/InternalExecutorProvider.java     |  65 ++++++
 .../com/github/copilot/ConfigCloneTest.java   |  19 +-
 .../github/copilot/CopilotSessionTest.java    |   2 +-
 .../copilot/CreateSessionReKeyEntryTest.java  |  44 ++--
 .../copilot/InternalExecutorProviderIT.java   | 108 ++++++++++
 .../InternalExecutorProviderProbe.java        |  74 +++++++
 .../copilot/InternalExecutorProviderTest.java |  55 +++++
 .../copilot/SessionRequestBuilderTest.java    |  75 +++++++
 27 files changed, 1587 insertions(+), 202 deletions(-)
 create mode 100644 src/main/java/com/github/copilot/InternalExecutorProvider.java
 create mode 100644 src/main/java/com/github/copilot/rpc/LargeToolOutputConfig.java
 create mode 100644 src/main/java25/com/github/copilot/InternalExecutorProvider.java
 create mode 100644 src/test/java/com/github/copilot/InternalExecutorProviderIT.java
 create mode 100644 src/test/java/com/github/copilot/InternalExecutorProviderProbe.java
 create mode 100644 src/test/java/com/github/copilot/InternalExecutorProviderTest.java

diff --git a/.github/actions/test-report/action.yml b/.github/actions/test-report/action.yml
index 52a093a68d..6ac1fcbc76 100644
--- a/.github/actions/test-report/action.yml
+++ b/.github/actions/test-report/action.yml
@@ -4,7 +4,7 @@ inputs:
   report-path:
     description: "Path to the test report XML files (glob pattern)"
     required: false
-    default: "target/surefire-reports*/TEST-*.xml"
+    default: "target/{surefire-reports*,failsafe-reports}/TEST-*.xml"
   jacoco-path:
     description: "Path to the JaCoCo XML report"
     required: false
@@ -17,13 +17,17 @@ inputs:
     description: "Name for the check run"
     required: false
     default: "Java SDK Test Results"
+  title:
+    description: "Title for the test report summary"
+    required: false
+    default: "Copilot Java SDK :: Test Results"
 runs:
   using: "composite"
   steps:
     - name: Generate Test Summary
       shell: bash
       run: |
-        echo "## 🧪 Copilot Java SDK :: Test Results" >> $GITHUB_STEP_SUMMARY
+        echo "## 🧪 ${{ inputs.title }}" >> $GITHUB_STEP_SUMMARY
         echo "" >> $GITHUB_STEP_SUMMARY
 
         if ls ${{ inputs.report-path }} 1>/dev/null 2>&1; then
@@ -148,7 +152,7 @@ runs:
           if [ -f "$JACOCO_CSV" ]; then
             extract_instruction_scope() {
               local scope=$1
-              awk -F',' -v scope="$scope" -v generated_prefix="com.github.copilot.sdk.generated" '
+              awk -F',' -v scope="$scope" -v generated_prefix="com.github.copilot.generated" '
                 NR > 1 {
                   is_generated = index($2, generated_prefix) == 1
                   if ((scope == "generated" && is_generated) ||
diff --git a/.github/workflows/build-test.yml b/.github/workflows/build-test.yml
index 29fd1fd119..dbc7406993 100644
--- a/.github/workflows/build-test.yml
+++ b/.github/workflows/build-test.yml
@@ -30,7 +30,7 @@ jobs:
       COPILOT_GITHUB_TOKEN: ${{ secrets.COPILOT_GITHUB_TOKEN }}
 
   java-sdk:
-    name: "Java SDK Tests"
+    name: "Java SDK Tests (JDK ${{ matrix.test-jdk }})"
     needs: smoke-test
     if: ${{ always() && needs.smoke-test.result != 'failure' }}
     permissions:
@@ -39,6 +39,10 @@ jobs:
       pull-requests: write
 
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        test-jdk: ["25", "17"]
     defaults:
       run:
         shell: bash
@@ -46,16 +50,29 @@ jobs:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           persist-credentials: false
-      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6
-        with:
-          node-version: 22
+
       - uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # v5
         with:
-          java-version: "17"
+          java-version: "25"
           distribution: "microsoft"
           cache: "maven"
 
+      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6
+        with:
+          node-version: 22
+
+      - name: Build SDK and set up test harness
+        run: mvn test-compile jar:jar
+
+      - name: Verify Javadoc generation
+        if: matrix.test-jdk == '25'
+        run: mvn javadoc:javadoc -q
+
+      - name: Verify CLI works
+        run: node target/copilot-sdk/nodejs/node_modules/@github/copilot/index.js --version
+
       - name: Run spotless check
+        if: matrix.test-jdk == '25'
         run: |
           mvn spotless:check
           if [ $? -ne 0 ]; then
@@ -64,30 +81,27 @@ jobs:
           fi
           echo "✅ spotless:check passed"
 
-      - name: Build SDK and clone test harness
-        run: mvn test-compile
-
-      - name: Verify Javadoc generation
-        run: mvn javadoc:javadoc -q
-
-      - name: Install Copilot CLI from cloned SDK
-        id: setup-copilot
-        run: |
-          # Install dependencies in the cloned SDK's nodejs directory
-          # This ensures we use the same CLI version as the test harness expects
-          cd target/copilot-sdk/nodejs
-          npm ci --ignore-scripts
-          echo "path=$(pwd)/node_modules/@github/copilot/index.js" >> $GITHUB_OUTPUT
+      - name: Run Java SDK tests (JDK 25)
+        if: matrix.test-jdk == '25'
+        env:
+          CI: "true"
+        run: mvn verify -Dskip.test.harness=true
 
-      - name: Verify CLI works
-        run: node ${{ steps.setup-copilot.outputs.path }} --version
+      - name: Switch to JDK 17
+        if: matrix.test-jdk == '17'
+        uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # v5
+        with:
+          java-version: "17"
+          distribution: "microsoft"
 
-      - name: Run Java SDK tests
+      - name: Run Java SDK tests (JDK 17, no recompilation)
+        if: matrix.test-jdk == '17'
         env:
           CI: "true"
-          COPILOT_GITHUB_TOKEN: ${{ secrets.COPILOT_GITHUB_TOKEN }}
-          COPILOT_CLI_PATH: ${{ steps.setup-copilot.outputs.path }}
-        run: mvn verify
+        run: |
+          echo "Running tests against JDK 25-built classes using JDK 17 runtime..."
+          java -version
+          mvn jacoco:prepare-agent@wire-up-coverage-instrumentation antrun:run@print-test-jdk-banner surefire:test failsafe:integration-test failsafe:verify jacoco:report@build-coverage-report-from-tests -Denforcer.skip=true
 
       - name: Validate reference-impl-sync completeness
         if: >-
@@ -123,7 +137,7 @@ jobs:
           fi
 
       - name: Upload test results for site generation
-        if: success() && github.ref == 'refs/heads/main'
+        if: success() && github.ref == 'refs/heads/main' && matrix.test-jdk == '25'
         uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7
         with:
           name: test-results-for-site
@@ -134,11 +148,11 @@ jobs:
           retention-days: 1
 
       - name: Generate JaCoCo badge
-        if: success() && github.ref == 'refs/heads/main'
+        if: success() && github.ref == 'refs/heads/main' && matrix.test-jdk == '25'
         run: .github/scripts/generate-coverage-badge.sh
 
       - name: Create PR for JaCoCo badge update
-        if: success() && github.ref == 'refs/heads/main'
+        if: success() && github.ref == 'refs/heads/main' && matrix.test-jdk == '25'
         uses: peter-evans/create-pull-request@5f6978faf089d4d20b00c7766989d076bb2fc7f1 # v7
         with:
           commit-message: "Update JaCoCo coverage badge"
@@ -151,3 +165,15 @@ jobs:
       - name: Generate Test Report Summary
         if: always()
         uses: ./.github/actions/test-report
+        with:
+          title: "Copilot Java SDK :: Test Results JDK ${{ matrix.test-jdk }}"
+
+      - name: Upload test results on failure
+        if: failure()
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7
+        with:
+          name: test-results-jdk-${{ matrix.test-jdk }}
+          path: |
+            target/surefire-reports/
+            target/surefire-reports-isolated/
+          retention-days: 7
diff --git a/README.md b/README.md
index 22b2f29cfc..46c01635ad 100644
--- a/README.md
+++ b/README.md
@@ -1,18 +1,14 @@
 # GitHub Copilot SDK for Java
 
-[![Build](https://github.com/github/copilot-sdk-java/actions/workflows/build-test.yml/badge.svg)](https://github.com/github/copilot-sdk-java/actions/workflows/build-test.yml)
-[![Site](https://github.com/github/copilot-sdk-java/actions/workflows/deploy-site.yml/badge.svg)](https://github.com/github/copilot-sdk-java/actions/workflows/deploy-site.yml)
-[![Handwritten Coverage](.github/badges/jacoco-handwritten.svg)](https://github.github.io/copilot-sdk-java/snapshot/jacoco/index.html)
-[![Generated Coverage](.github/badges/jacoco-generated.svg)](https://github.github.io/copilot-sdk-java/snapshot/jacoco/index.html)
-[![Documentation](https://img.shields.io/badge/docs-online-brightgreen)](https://github.github.io/copilot-sdk-java/)
+[![Build](https://github.com/github/copilot-sdk/actions/workflows/java-sdk-tests.yml/badge.svg)](https://github.com/github/copilot-sdk/actions/workflows/java-sdk-tests.yml)
 [![Java 17+](https://img.shields.io/badge/Java-17%2B-blue?logo=openjdk&logoColor=white)](https://openjdk.org/)
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
 
 #### Latest release
-[![GitHub Release Date](https://img.shields.io/github/release-date/github/copilot-sdk-java)](https://github.com/github/copilot-sdk-java/releases)
-[![GitHub Release](https://img.shields.io/github/v/release/github/copilot-sdk-java)](https://github.com/github/copilot-sdk-java/releases)
+
+[![GitHub Release Date](https://img.shields.io/github/release-date/github/copilot-sdk)](https://github.com/github/copilot-sdk/releases)
+[![GitHub Release](https://img.shields.io/github/v/release/github/copilot-sdk)](https://github.com/github/copilot-sdk/releases)
 [![Maven Central](https://img.shields.io/maven-central/v/com.github/copilot-sdk-java)](https://central.sonatype.com/artifact/com.github/copilot-sdk-java)
-[![Documentation](https://img.shields.io/badge/docs-latest-brightgreen)](https://github.github.io/copilot-sdk-java/latest/)
 [![Javadoc](https://javadoc.io/badge2/com.github/copilot-sdk-java/javadoc.svg?q=1)](https://javadoc.io/doc/com.github/copilot-sdk-java/latest/index.html)
 
 ## Background
@@ -23,10 +19,10 @@ Java SDK for programmatic control of GitHub Copilot CLI, enabling you to build A
 
 ## Installation
 
-### Requirements
+### Runtime requirements
 
-- Java 17 or later. **JDK 25 recommended**. Selecting JDK 25 enables the use of virtual threads, as shown in the [Quick Start](#quick-start).
-- GitHub Copilot CLI 1.0.17 or later installed and in `PATH` (or provide custom `cliPath`)
+- Java 17 or later. **JDK 25 recommended**. The distributed jar is a multi-release jar (MR-JAR) and is compiled on JDK 25 with `maven.compiler.release` set to 17. This means, when run on JDK 25 and later, the SDK automatically uses virtual threads for its default internal executor.
+- GitHub Copilot CLI 1.0.55-5. or later installed and in `PATH` (or provide custom `cliPath`)
 
 ### Maven
 
@@ -34,10 +30,16 @@ Java SDK for programmatic control of GitHub Copilot CLI, enabling you to build A
 <dependency>
     <groupId>com.github</groupId>
     <artifactId>copilot-sdk-java</artifactId>
-    <version>1.0.0-beta-8-java.0</version>
+    <version>1.0.0-beta-10-java.0</version>
 </dependency>
 ```
 
+### Gradle
+
+```groovy
+implementation 'com.github:copilot-sdk-java:1.0.0-beta-10-java.0'
+
+
 #### Snapshot Builds
 
 Snapshot builds of the next development version are published to Maven Central Snapshots. To use them, add the repository and update the dependency version in your `pom.xml`:
@@ -54,14 +56,14 @@ Snapshot builds of the next development version are published to Maven Central S
 <dependency>
     <groupId>com.github</groupId>
     <artifactId>copilot-sdk-java</artifactId>
-    <version>1.0.0-beta-8-java.1-SNAPSHOT</version>
+    <version>1.0.0-beta-10-java.0-SNAPSHOT</version>
 </dependency>
 ```
 
 ### Gradle
 
 ```groovy
-implementation 'com.github:copilot-sdk-java:1.0.0-beta-8-java.0'
+implementation 'com.github:copilot-sdk-java:1.0.0-beta-10-java.0-SNAPSHOT'
 ```
 
 ## Quick Start
@@ -70,23 +72,16 @@ implementation 'com.github:copilot-sdk-java:1.0.0-beta-8-java.0'
 import com.github.copilot.CopilotClient;
 import com.github.copilot.generated.AssistantMessageEvent;
 import com.github.copilot.generated.SessionUsageInfoEvent;
-import com.github.copilot.rpc.CopilotClientOptions;
 import com.github.copilot.rpc.MessageOptions;
 import com.github.copilot.rpc.PermissionHandler;
 import com.github.copilot.rpc.SessionConfig;
 
-import java.util.concurrent.Executors;
-
 public class CopilotSDK {
     public static void main(String[] args) throws Exception {
         var lastMessage = new String[]{null};
 
         // Create and start client
-        try (var client = new CopilotClient()) {  // JDK 25+: comment out this line
-        // JDK 25+: uncomment the following 3 lines for virtual thread support
-        // var options = new CopilotClientOptions()
-        //     .setExecutor(Executors.newVirtualThreadPerTaskExecutor());
-        // try (var client = new CopilotClient(options)) {
+        try (var client = new CopilotClient()) {
             client.start().get();
 
             // Create a session
@@ -130,31 +125,20 @@ See the full source of [`jbang-example.java`](jbang-example.java) for a complete
 Or run it directly from the repository:
 
 ```bash
-jbang https://github.com/github/copilot-sdk-java/blob/latest/jbang-example.java
+jbang https://github.com/github/copilot-sdk/blob/main/java/jbang-example.java
 ```
 
-## Documentation
-
-📚 **[Full Documentation](https://github.github.io/copilot-sdk-java/)** — Complete API reference, advanced usage examples, and guides.
-
-### Quick Links
-
-- [Getting Started](https://github.github.io/copilot-sdk-java/latest/documentation.html)
-- [Javadoc API Reference](https://github.github.io/copilot-sdk-java/latest/apidocs/)
-- [MCP Servers Integration](https://github.github.io/copilot-sdk-java/latest/mcp.html)
-- [Cookbook](src/site/markdown/cookbook/) — Practical recipes for common use cases
-
 ## Projects Using This SDK
 
-| Project | Description |
-|---------|-------------|
+| Project                                                                       | Description                                |
+| ----------------------------------------------------------------------------- | ------------------------------------------ |
 | [JMeter Copilot Plugin](https://github.com/brunoborges/jmeter-copilot-plugin) | JMeter plugin for AI-assisted load testing |
 
 > Want to add your project? Open a PR!
 
 ## CI/CD Workflows
 
-This project uses several GitHub Actions workflows for building, testing, releasing, and syncing with the reference implementation SDK. 
+This project uses several GitHub Actions workflows for building, testing, releasing, and syncing with the reference implementation SDK.
 
 See [WORKFLOWS.md](docs/WORKFLOWS.md) for a full overview and details on each workflow.
 
@@ -169,21 +153,28 @@ This SDK tracks the official [Copilot SDK](https://github.com/github/copilot-sdk
 **Automated sync** — A [scheduled GitHub Actions workflow](.github/workflows/reference-impl-sync.yml) runs on the schedule specified in that file. It checks for new reference implementation commits since the last merge (tracked in [`.lastmerge`](.lastmerge)), and if changes are found, creates an issue labeled `reference-impl-sync` and assigns it to the GitHub Copilot coding agent. Any previously open `reference-impl-sync` issues are automatically closed. The sync also updates the `@github/copilot` version in both `pom.xml` and `scripts/codegen/package.json` to keep schemas and test CLI in lockstep.
 
 **Reusable prompt** — The merge workflow is defined in [`agentic-merge-reference-impl.prompt.md`](.github/prompts/agentic-merge-reference-impl.prompt.md). It can be triggered manually from:
+
 - **VS Code Copilot Chat** — type `/agentic-merge-reference-impl`
 - **GitHub Copilot CLI** — use `copilot` CLI with the same skill reference
 
 ### Development Setup
 
+Requires JDK 25 or later for development.
+
 ```bash
 # Clone the repository
-git clone https://github.com/github/copilot-sdk-java.git
-cd copilot-sdk-java
+git clone https://github.com/github/copilot-sdk.git
+cd copilot-sdk/java
 
 # Enable git hooks for code formatting
 git config core.hooksPath .githooks
 
-# Build and test
+# Build and test with JDK 25
 mvn clean verify
+
+# Set your paths for JDK 17
+# Run the JDK 25 built jar with JDK 17 JVM for tests. Do not re-compile the jar.
+mvn jacoco:prepare-agent@wire-up-coverage-instrumentation antrun:run@print-test-jdk-banner surefire:test failsafe:integration-test failsafe:verify jacoco:report@build-coverage-report-from-tests -Denforcer.skip=true
 ```
 
 The tests require the official [copilot-sdk](https://github.com/github/copilot-sdk) test harness, which is automatically cloned during build.
@@ -204,12 +195,3 @@ See [SECURITY.md](SECURITY.md) for reporting security vulnerabilities.
 
 MIT — see [LICENSE](LICENSE) for details.
 
-## Acknowledgement
-
-- Initially developed with Copilot and [Bruno Borges](https://www.linkedin.com/in/brunocborges/).
-
-## Star History
-
-[![Star History Chart](https://api.star-history.com/svg?repos=github/copilot-sdk-java&type=Date)](https://www.star-history.com/#github/copilot-sdk-java&Date)
-
-⭐ Drop a star if you find this useful!
diff --git a/jbang-example.java b/jbang-example.java
index 7482eee3df..a3616e2636 100644
--- a/jbang-example.java
+++ b/jbang-example.java
@@ -1,5 +1,5 @@
 ///usr/bin/env jbang "$0" "$@" ; exit $?
-//DEPS com.github:copilot-sdk-java:1.0.0-beta-8-java.0
+//DEPS com.github:copilot-sdk-java:1.0.0-beta-java.4
 import com.github.copilot.CopilotClient;
 import com.github.copilot.generated.AssistantMessageEvent;
 import com.github.copilot.generated.SessionUsageInfoEvent;
diff --git a/pom.xml b/pom.xml
index bd6425a1b7..fe267e2361 100644
--- a/pom.xml
+++ b/pom.xml
@@ -7,7 +7,7 @@
 
     <groupId>com.github</groupId>
     <artifactId>copilot-sdk-java</artifactId>
-    <version>1.0.0-beta-8-java.1-SNAPSHOT</version>
+    <version>1.0.0-beta-10-java.0-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <name>GitHub Copilot SDK :: Java</name>
@@ -245,6 +245,18 @@
                             </target>
                         </configuration>
                     </execution>
+                    <execution>
+                        <id>print-test-jdk-banner</id>
+                        <phase>process-test-classes</phase>
+                        <goals>
+                            <goal>run</goal>
+                        </goals>
+                        <configuration>
+                            <target>
+                                <echo level="warning" message="⚠⚠⚠ Using Java ${java.version} (${java.vendor}) to run tests." />
+                            </target>
+                        </configuration>
+                    </execution>
                 </executions>
                 <dependencies>
                     <!-- Required for if:set and unless:set -->
@@ -307,6 +319,33 @@
                     </execution>
                 </executions>
             </plugin>
+            <!--
+                Failsafe runs integration tests against the actually packaged
+                JAR (after the package phase). Used to validate multi-release
+                JAR behaviour end-to-end without reflecting on private fields
+                or hand-rolling a synthetic JAR. See
+                src/test/java/com/github/copilot/InternalExecutorProviderIT.java.
+            -->
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-failsafe-plugin</artifactId>
+                <version>3.5.5</version>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>integration-test</goal>
+                            <goal>verify</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                    <systemPropertyVariables>
+                        <project.build.directory>${project.build.directory}</project.build.directory>
+                        <project.build.finalName>${project.build.finalName}</project.build.finalName>
+                        <project.build.testOutputDirectory>${project.build.testOutputDirectory}</project.build.testOutputDirectory>
+                    </systemPropertyVariables>
+                </configuration>
+            </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
@@ -321,7 +360,7 @@
                         CompactionTest) where snapshot matching can be sensitive
                         to non-deterministic compaction behaviour.
                         Revisit this once this issue is successfully resolved.
-                        https://github.com/github/copilot-sdk/issues/1227 
+                        https://github.com/github/copilot-sdk/issues/1227
                     -->
                     <rerunFailingTestsCount>2</rerunFailingTestsCount>
                     <systemPropertyVariables>
@@ -447,6 +486,10 @@
                         <configuration>
                             <dataFile>${project.build.directory}/jacoco-test-results/sdk-tests.exec</dataFile>
                             <outputDirectory>${project.reporting.outputDirectory}/jacoco-coverage</outputDirectory>
+                            <excludes>
+                                <!-- Exclude multi-release classes to avoid duplicate class analysis. -->
+                                <exclude>META-INF/versions/**/*.class</exclude>
+                            </excludes>
                         </configuration>
                     </execution>
                 </executions>
@@ -693,6 +736,88 @@
                 <surefire.jvm.args>-XX:+EnableDynamicAgentLoading</surefire.jvm.args>
             </properties>
         </profile>
+        <profile>
+            <id>java25-multi-release</id>
+            <activation>
+                <jdk>[25,)</jdk>
+            </activation>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-compiler-plugin</artifactId>
+                        <executions>
+                            <execution>
+                                <id>compile-java25</id>
+                                <phase>compile</phase>
+                                <goals>
+                                    <goal>compile</goal>
+                                </goals>
+                                <configuration>
+                                    <release>25</release>
+                                    <useIncrementalCompilation>false</useIncrementalCompilation>
+                                    <compileSourceRoots>
+                                        <compileSourceRoot>${project.basedir}/src/main/java25</compileSourceRoot>
+                                    </compileSourceRoots>
+                                    <multiReleaseOutput>true</multiReleaseOutput>
+                                </configuration>
+                            </execution>
+                        </executions>
+                    </plugin>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-jar-plugin</artifactId>
+                        <configuration>
+                            <archive>
+                                <manifestEntries>
+                                    <Multi-Release>true</Multi-Release>
+                                </manifestEntries>
+                            </archive>
+                        </configuration>
+                    </plugin>
+                    <!--
+                        Structural guard: when this profile is active (JDK 25+
+                        builds), assert that the packaged JAR contains the
+                        JDK 25 multi-release overlay class. Catches accidental
+                        profile-disable / classifier / shading regressions
+                        before the failsafe IT runs.
+                    -->
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-antrun-plugin</artifactId>
+                        <executions>
+                            <execution>
+                                <id>verify-java25-overlay</id>
+                                <phase>package</phase>
+                                <goals>
+                                    <goal>run</goal>
+                                </goals>
+                                <configuration>
+                                    <target>
+                                        <condition property="java25.overlay.present">
+                                            <resourceexists>
+                                                <zipentry zipfile="${project.build.directory}/${project.build.finalName}.jar"
+                                                          name="META-INF/versions/25/com/github/copilot/InternalExecutorProvider.class"/>
+                                            </resourceexists>
+                                        </condition>
+                                        <fail unless="java25.overlay.present">
+JDK 25 multi-release overlay class is missing from the packaged JAR.
+Expected entry: META-INF/versions/25/com/github/copilot/InternalExecutorProvider.class
+JAR: ${project.build.directory}/${project.build.finalName}.jar
+
+This usually means the 'java25-multi-release' Maven profile did not activate
+(e.g. the build is running on a JDK older than 25) or maven-compiler-plugin
+did not produce the multi-release output. Re-build on JDK 25+ and verify the
+'compile-java25' execution ran during the 'compile' phase.
+                                        </fail>
+                                    </target>
+                                </configuration>
+                            </execution>
+                        </executions>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
         <!-- Skip git-clone + npm install of the copilot-sdk test harness -->
         <profile>
             <id>skip-test-harness</id>
diff --git a/scripts/compare-standalone-to-monorepo.sh b/scripts/compare-standalone-to-monorepo.sh
index ad329fdb1f..34ac23ec65 100755
--- a/scripts/compare-standalone-to-monorepo.sh
+++ b/scripts/compare-standalone-to-monorepo.sh
@@ -176,6 +176,35 @@ else
     LASTMERGE_STATUS="missing-both"
 fi
 
+# ── Compare README.md (standalone README.md ↔ monorepo java/README.md) ────────
+README_STATUS=""
+STANDALONE_README="${STANDALONE}/README.md"
+MONO_README="${MONO_JAVA}/README.md"
+
+if [ -f "$STANDALONE_README" ] && [ -f "$MONO_README" ]; then
+    if diff -q "$STANDALONE_README" "$MONO_README" >/dev/null 2>&1; then
+        README_STATUS="identical"
+        SAME_COUNT=$((SAME_COUNT + 1))
+    else
+        README_STATUS="differ"
+        DIFFER_COUNT=$((DIFFER_COUNT + 1))
+        DIFFER_LIST="${DIFFER_LIST}README.md
+"
+    fi
+elif [ -f "$STANDALONE_README" ] && [ ! -f "$MONO_README" ]; then
+    README_STATUS="only-standalone"
+    MISSING_FROM_MONO_COUNT=$((MISSING_FROM_MONO_COUNT + 1))
+    MISSING_FROM_MONO_LIST="${MISSING_FROM_MONO_LIST}README.md
+"
+elif [ ! -f "$STANDALONE_README" ] && [ -f "$MONO_README" ]; then
+    README_STATUS="only-monorepo"
+    MISSING_FROM_STANDALONE_COUNT=$((MISSING_FROM_STANDALONE_COUNT + 1))
+    MISSING_FROM_STANDALONE_LIST="${MISSING_FROM_STANDALONE_LIST}README.md
+"
+else
+    README_STATUS="missing-both"
+fi
+
 STANDALONE_TOTAL=$(wc -l < "$TMPFILE_STANDALONE" | tr -d ' ')
 MONO_TOTAL=$(wc -l < "$TMPFILE_MONO" | tr -d ' ')
 
@@ -202,6 +231,19 @@ else
     echo ".lastmerge: not found in either location"
 fi
 
+# README.md status
+if [ "$README_STATUS" = "identical" ]; then
+    echo "README.md: identical"
+elif [ "$README_STATUS" = "differ" ]; then
+    echo "README.md: DIFFERS"
+elif [ "$README_STATUS" = "only-standalone" ]; then
+    echo "README.md: only in standalone"
+elif [ "$README_STATUS" = "only-monorepo" ]; then
+    echo "README.md: only in monorepo"
+else
+    echo "README.md: not found in either location"
+fi
+
 # scripts/codegen/java.ts status
 if [ "$JAVATS_STATUS" = "identical" ]; then
     echo "scripts/codegen/java.ts: identical"
@@ -253,7 +295,7 @@ if [ "$SHOW_DIFF" = true ] && [ "$DIFFER_COUNT" -gt 0 ]; then
     echo "Unified diffs for differing files:"
     echo "================================================================================"
     printf '%s' "$DIFFER_LIST" | while IFS= read -r f; do
-        if [ -n "$f" ] && [ "$f" != ".lastmerge" ]; then
+        if [ -n "$f" ] && [ "$f" != ".lastmerge" ] && [ "$f" != "README.md" ]; then
             echo ""
             echo "--- standalone/$f"
             echo "+++ monorepo/java/$f"
@@ -262,6 +304,14 @@ if [ "$SHOW_DIFF" = true ] && [ "$DIFFER_COUNT" -gt 0 ]; then
     done
 fi
 
+# ── Optional README.md diff (paths differ between repos) ─────────────
+if [ "$SHOW_DIFF" = true ] && [ "$README_STATUS" = "differ" ]; then
+    echo ""
+    echo "--- standalone/README.md"
+    echo "+++ monorepo/java/README.md"
+    diff -u "${STANDALONE}/README.md" "${MONO_JAVA}/README.md" || true
+fi
+
 # ── Optional .lastmerge commit log comparison ────────────────────────
 if [ "$SHOW_DIFF" = true ] && [ "$LASTMERGE_STATUS" = "differ" ]; then
     STANDALONE_HASH=$(cat "$STANDALONE_LASTMERGE" | tr -d '[:space:]')
diff --git a/src/main/java/com/github/copilot/CopilotClient.java b/src/main/java/com/github/copilot/CopilotClient.java
index 662b66c7b4..36a3c78d1b 100644
--- a/src/main/java/com/github/copilot/CopilotClient.java
+++ b/src/main/java/com/github/copilot/CopilotClient.java
@@ -14,6 +14,7 @@
 import java.util.concurrent.CompletionException;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.Executor;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.RejectedExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.logging.Level;
@@ -80,7 +81,24 @@ public final class CopilotClient implements AutoCloseable {
      */
     public static final int AUTOCLOSEABLE_TIMEOUT_SECONDS = 10;
     private static final int FORCE_KILL_TIMEOUT_SECONDS = 10;
+
+    /**
+     * One-shot dispatcher used to run the owned-executor shutdown off any caller
+     * thread that might itself belong to that executor (e.g. the
+     * {@link #forceStop()} continuation, which is chained off async work scheduled
+     * on the internal executor). Spawning a fresh daemon thread guarantees
+     * {@link java.util.concurrent.ExecutorService#awaitTermination(long, TimeUnit)}
+     * is never called from inside the very executor it is waiting on.
+     */
+    private static final Executor SHUTDOWN_DISPATCHER = runnable -> {
+        Thread t = new Thread(runnable, "copilot-client-shutdown");
+        t.setDaemon(true);
+        t.start();
+    };
+
     private final CopilotClientOptions options;
+    private final Executor executor;
+    private final boolean executorCanBeShutdown;
     private final CliServerManager serverManager;
     private final LifecycleEventManager lifecycleManager = new LifecycleEventManager();
     private final Map<String, CopilotSession> sessions = new ConcurrentHashMap<>();
@@ -168,6 +186,10 @@ public CopilotClient(CopilotClientOptions options) {
             this.optionsPort = null;
         }
 
+        InternalExecutorProvider executorProvider = new InternalExecutorProvider(this.options.getExecutor());
+        this.executor = executorProvider.get();
+        this.executorCanBeShutdown = executorProvider.canBeShutdown();
+
         this.serverManager = new CliServerManager(this.options);
         this.serverManager.setConnectionToken(this.effectiveConnectionToken);
     }
@@ -191,11 +213,8 @@ public CompletableFuture<Void> start() {
     private CompletableFuture<Connection> startCore() {
         LOG.fine("Starting Copilot client");
 
-        Executor exec = options.getExecutor();
         try {
-            return exec != null
-                    ? CompletableFuture.supplyAsync(this::startCoreBody, exec)
-                    : CompletableFuture.supplyAsync(this::startCoreBody);
+            return CompletableFuture.supplyAsync(this::startCoreBody, executor);
         } catch (RejectedExecutionException e) {
             return CompletableFuture.failedFuture(e);
         }
@@ -224,8 +243,7 @@ private Connection startCoreBody() {
             Connection connection = new Connection(rpc, process, new ServerRpc(rpc::invoke));
 
             // Register handlers for server-to-client calls
-            RpcHandlerDispatcher dispatcher = new RpcHandlerDispatcher(sessions, lifecycleManager::dispatch,
-                    options.getExecutor());
+            RpcHandlerDispatcher dispatcher = new RpcHandlerDispatcher(sessions, lifecycleManager::dispatch, executor);
             dispatcher.registerHandlers(rpc);
 
             // Verify protocol version
@@ -323,7 +341,6 @@ private static boolean isUnsupportedConnectMethod(JsonRpcException ex) {
      */
     public CompletableFuture<Void> stop() {
         var closeFutures = new ArrayList<CompletableFuture<Void>>();
-        Executor exec = options.getExecutor();
 
         for (CopilotSession session : new ArrayList<>(sessions.values())) {
             Runnable closeTask = () -> {
@@ -335,9 +352,7 @@ public CompletableFuture<Void> stop() {
             };
             CompletableFuture<Void> future;
             try {
-                future = exec != null
-                        ? CompletableFuture.runAsync(closeTask, exec)
-                        : CompletableFuture.runAsync(closeTask);
+                future = CompletableFuture.runAsync(closeTask, executor);
             } catch (RejectedExecutionException e) {
                 LOG.log(Level.WARNING, "Executor rejected session close task; closing inline", e);
                 closeTask.run();
@@ -359,7 +374,12 @@ public CompletableFuture<Void> stop() {
     public CompletableFuture<Void> forceStop() {
         disposed = true;
         sessions.clear();
-        return cleanupConnection();
+        // Dispatch the blocking shutdownOwnedExecutor() on a dedicated thread:
+        // cleanupConnection() is chained off async work running on the owned
+        // executor, so a plain whenComplete(...) here could land the awaitTermination
+        // call on one of the very threads it is waiting to drain, forcing the full
+        // AUTOCLOSEABLE_TIMEOUT_SECONDS timeout followed by shutdownNow().
+        return cleanupConnection().whenCompleteAsync((ignored, error) -> shutdownOwnedExecutor(), SHUTDOWN_DISPATCHER);
     }
 
     private CompletableFuture<Void> cleanupConnection() {
@@ -443,33 +463,57 @@ public CompletableFuture<CopilotSession> createSession(SessionConfig config) {
         }
         return ensureConnected().thenCompose(connection -> {
             long totalNanos = System.nanoTime();
-            // Pre-generate session ID so the session can be registered before the RPC call,
-            // ensuring no events emitted by the CLI during creation are lost.
-            String sessionId = config.getSessionId() != null
-                    ? config.getSessionId()
-                    : java.util.UUID.randomUUID().toString();
+            // For cloud sessions, let the CLI/server assign the session id
+            // and register the session lazily once the response arrives. For
+            // non-cloud sessions we generate the id client-side (when the
+            // caller didn't supply one) so the session can be registered
+            // BEFORE the RPC — the CLI may issue session-scoped requests
+            // (e.g. sessionFs.writeFile for workspace metadata) during
+            // session.create processing, before it has sent the response.
+            String callerSessionId = config.getSessionId();
+            boolean useServerGeneratedId = config.getCloud() != null
+                    && (callerSessionId == null || callerSessionId.isEmpty());
+            String localSessionId = useServerGeneratedId
+                    ? null
+                    : (callerSessionId != null && !callerSessionId.isEmpty()
+                            ? callerSessionId
+                            : java.util.UUID.randomUUID().toString());
+
+            // Extract transform callbacks from the system message config. Callbacks
+            // are registered with the session; a wire-safe copy of the system
+            // message (with transform sections replaced by action="transform") is
+            // used in the RPC request.
+            var extracted = SessionRequestBuilder.extractTransformCallbacks(config.getSystemMessage());
 
-            long setupNanos = System.nanoTime();
-            var session = new CopilotSession(sessionId, connection.rpc);
-            if (options.getExecutor() != null) {
-                session.setExecutor(options.getExecutor());
-            }
-            SessionRequestBuilder.configureSession(session, config);
-            sessions.put(sessionId, session);
-            LoggingHelpers.logTiming(LOG, Level.FINE,
-                    "CopilotClient.createSession local setup complete. Elapsed={Elapsed}, SessionId=" + sessionId,
-                    setupNanos);
+            // Creates the session, wires up handlers, and registers it in the
+            // sessions map.
+            java.util.function.Function<String, CopilotSession> initializeSession = sid -> {
+                long setupNanos = System.nanoTime();
+                var s = new CopilotSession(sid, connection.rpc);
+                s.setExecutor(executor);
+                SessionRequestBuilder.configureSession(s, config);
+                if (extracted.transformCallbacks() != null) {
+                    s.registerTransformCallbacks(extracted.transformCallbacks());
+                }
+                sessions.put(sid, s);
+                LoggingHelpers.logTiming(LOG, Level.FINE,
+                        "CopilotClient.createSession local setup complete. Elapsed={Elapsed}, SessionId=" + sid,
+                        setupNanos);
+                return s;
+            };
 
-            // Extract transform callbacks from the system message config.
-            // Callbacks are registered with the session; a wire-safe copy of the
-            // system message (with transform sections replaced by action="transform")
-            // is used in the RPC request.
-            var extracted = SessionRequestBuilder.extractTransformCallbacks(config.getSystemMessage());
-            if (extracted.transformCallbacks() != null) {
-                session.registerTransformCallbacks(extracted.transformCallbacks());
+            String[] registeredIdHolder = new String[1];
+            CopilotSession[] preRegisteredSessionHolder = new CopilotSession[1];
+
+            // Pre-register non-cloud sessions BEFORE issuing the RPC so any
+            // session-scoped requests the CLI emits during session.create
+            // processing can be routed to the correct handlers.
+            if (localSessionId != null) {
+                preRegisteredSessionHolder[0] = initializeSession.apply(localSessionId);
+                registeredIdHolder[0] = localSessionId;
             }
 
-            var request = SessionRequestBuilder.buildCreateRequest(config, sessionId);
+            var request = SessionRequestBuilder.buildCreateRequest(config, localSessionId);
             if (extracted.wireSystemMessage() != config.getSystemMessage()) {
                 request.setSystemMessage(extracted.wireSystemMessage());
             }
@@ -477,31 +521,41 @@ public CompletableFuture<CopilotSession> createSession(SessionConfig config) {
             // Empty mode: validate availableTools and set toolFilterPrecedence
             if (options.getMode() == CopilotClientMode.EMPTY) {
                 if (config.getAvailableTools() == null) {
+                    if (registeredIdHolder[0] != null) {
+                        sessions.remove(registeredIdHolder[0]);
+                    }
                     throw new IllegalArgumentException(
                             "CopilotClient is in Mode = EMPTY but the session config did not specify "
                                     + "availableTools. Empty mode requires every session to explicitly opt into "
                                     + "the tools it wants — e.g. setAvailableTools(new ToolSet().addBuiltIn(BuiltInTools.ISOLATED)).");
                 }
                 request.setToolFilterPrecedence("excluded");
+                if (request.getMcpOAuthTokenStorage() == null) {
+                    request.setMcpOAuthTokenStorage("in-memory");
+                }
             }
 
             long rpcNanos = System.nanoTime();
             return connection.rpc.invoke("session.create", request, CreateSessionResponse.class)
                     .thenCompose(response -> {
+                        String returnedId = response.sessionId();
                         LoggingHelpers.logTiming(LOG, Level.FINE,
                                 "CopilotClient.createSession session creation request completed. Elapsed={Elapsed}, SessionId="
-                                        + sessionId,
+                                        + (returnedId != null ? returnedId : localSessionId),
                                 rpcNanos);
+                        if (returnedId == null || returnedId.isEmpty()) {
+                            throw new RuntimeException("session.create response did not include a sessionId");
+                        }
+                        if (localSessionId != null && !localSessionId.equals(returnedId)) {
+                            throw new RuntimeException("session.create returned sessionId " + returnedId
+                                    + " but the caller requested " + localSessionId);
+                        }
+                        CopilotSession session = preRegisteredSessionHolder[0] != null
+                                ? preRegisteredSessionHolder[0]
+                                : initializeSession.apply(returnedId);
+                        registeredIdHolder[0] = returnedId;
                         session.setWorkspacePath(response.workspacePath());
                         session.setCapabilities(response.capabilities());
-                        // If the server returned a different sessionId (e.g. a v2 CLI that ignores
-                        // the client-supplied ID), re-key the sessions map.
-                        String returnedId = response.sessionId();
-                        if (returnedId != null && !returnedId.equals(sessionId)) {
-                            sessions.remove(sessionId);
-                            session.setActiveSessionId(returnedId);
-                            sessions.put(returnedId, session);
-                        }
 
                         return updateSessionOptionsForMode(session, config.getSkipCustomInstructions().orElse(null),
                                 config.getCustomAgentsLocalOnly().orElse(null),
@@ -509,19 +563,17 @@ public CompletableFuture<CopilotSession> createSession(SessionConfig config) {
                                 config.getManageScheduleEnabled().orElse(null)).thenApply(v -> {
                                     LoggingHelpers.logTiming(LOG, Level.FINE,
                                             "CopilotClient.createSession complete. Elapsed={Elapsed}, SessionId="
-                                                    + sessionId,
+                                                    + session.getSessionId(),
                                             totalNanos);
                                     return session;
                                 });
                     }).exceptionally(ex -> {
-                        sessions.remove(sessionId);
-                        // Also remove the re-keyed entry if the server returned a different ID
-                        String activeId = session.getSessionId();
-                        if (!sessionId.equals(activeId)) {
-                            sessions.remove(activeId);
+                        if (registeredIdHolder[0] != null) {
+                            sessions.remove(registeredIdHolder[0]);
                         }
                         LoggingHelpers.logTiming(LOG, Level.WARNING, ex,
-                                "CopilotClient.createSession failed. Elapsed={Elapsed}, SessionId=" + sessionId,
+                                "CopilotClient.createSession failed. Elapsed={Elapsed}, SessionId="
+                                        + (registeredIdHolder[0] != null ? registeredIdHolder[0] : "<unassigned>"),
                                 totalNanos);
                         throw ex instanceof RuntimeException re ? re : new RuntimeException(ex);
                     });
@@ -565,9 +617,7 @@ public CompletableFuture<CopilotSession> resumeSession(String sessionId, ResumeS
             // Register the session before the RPC call to avoid missing early events.
             long setupNanos = System.nanoTime();
             var session = new CopilotSession(sessionId, connection.rpc);
-            if (options.getExecutor() != null) {
-                session.setExecutor(options.getExecutor());
-            }
+            session.setExecutor(executor);
             SessionRequestBuilder.configureSession(session, config);
             sessions.put(sessionId, session);
             LoggingHelpers.logTiming(LOG, Level.FINE,
@@ -595,6 +645,9 @@ public CompletableFuture<CopilotSession> resumeSession(String sessionId, ResumeS
                                     + "the tools it wants — e.g. setAvailableTools(new ToolSet().addBuiltIn(BuiltInTools.ISOLATED)).");
                 }
                 request.setToolFilterPrecedence("excluded");
+                if (request.getMcpOAuthTokenStorage() == null) {
+                    request.setMcpOAuthTokenStorage("in-memory");
+                }
             }
 
             long rpcNanos = System.nanoTime();
@@ -1111,6 +1164,44 @@ public void close() {
             stop().get(AUTOCLOSEABLE_TIMEOUT_SECONDS, TimeUnit.SECONDS);
         } catch (Exception e) {
             LOG.log(Level.FINE, "Error during close", e);
+        } finally {
+            shutdownOwnedExecutor();
+        }
+    }
+
+    private void shutdownOwnedExecutor() {
+        if (!executorCanBeShutdown) {
+            return;
+        }
+
+        ExecutorService serviceToShutdown = executor instanceof ExecutorService es ? es : null;
+        if (serviceToShutdown == null) {
+            LOG.log(Level.FINE, "Executor is not an ExecutorService; skipping shutdown");
+            return;
+        }
+
+        // Short-circuit when the owned executor is already shut down. close() and
+        // forceStop() can each call this method (e.g. forceStop() invoked before a
+        // subsequent close() in user code), and re-entering shutdown() +
+        // awaitTermination()
+        // is redundant. Logging at FINE aids diagnostics without spamming normal
+        // output.
+        if (serviceToShutdown.isShutdown()) {
+            LOG.log(Level.FINE, "Owned executor was already shut down; skipping redundant shutdown call.");
+            return;
+        }
+
+        serviceToShutdown.shutdown();
+        try {
+            if (!serviceToShutdown.awaitTermination(AUTOCLOSEABLE_TIMEOUT_SECONDS, TimeUnit.SECONDS)) {
+                LOG.log(Level.FINE, "Owned executor did not terminate within {0} seconds; forcing shutdown.",
+                        AUTOCLOSEABLE_TIMEOUT_SECONDS);
+                serviceToShutdown.shutdownNow();
+            }
+        } catch (InterruptedException e) {
+            serviceToShutdown.shutdownNow();
+            Thread.currentThread().interrupt();
+            LOG.log(Level.FINE, "Interrupted while waiting for owned executor to terminate", e);
         }
     }
 
diff --git a/src/main/java/com/github/copilot/CopilotSession.java b/src/main/java/com/github/copilot/CopilotSession.java
index 2651edb0b7..64c02d8b8f 100644
--- a/src/main/java/com/github/copilot/CopilotSession.java
+++ b/src/main/java/com/github/copilot/CopilotSession.java
@@ -478,6 +478,7 @@ public CompletableFuture<String> send(MessageOptions options) {
         request.setMode(options.getMode());
         request.setAgentMode(options.getAgentMode());
         request.setRequestHeaders(options.getRequestHeaders());
+        request.setDisplayPrompt(options.getDisplayPrompt());
 
         return rpc.invoke("session.send", request, SendMessageResponse.class).thenApply(SendMessageResponse::messageId);
     }
@@ -1728,6 +1729,35 @@ public CompletableFuture<Void> setModel(String model, String reasoningEffort) {
      */
     public CompletableFuture<Void> setModel(String model, String reasoningEffort,
             com.github.copilot.rpc.ModelCapabilitiesOverride modelCapabilities) {
+        return setModel(model, reasoningEffort, null, modelCapabilities);
+    }
+
+    /**
+     * Changes the model for this session with optional reasoning effort, reasoning
+     * summary mode, and capability overrides.
+     * <p>
+     * The new model takes effect for the next message. Conversation history is
+     * preserved.
+     *
+     * @param model
+     *            the model ID to switch to (e.g., {@code "gpt-4.1"})
+     * @param reasoningEffort
+     *            reasoning effort level; {@code null} to use default
+     * @param reasoningSummary
+     *            reasoning summary mode ({@code "none"}, {@code "concise"}, or
+     *            {@code "detailed"}); {@code null} to use default. Use
+     *            {@code "none"} to suppress summary output regardless of whether
+     *            reasoning is enabled.
+     * @param modelCapabilities
+     *            per-property overrides for model capabilities; {@code null} to use
+     *            runtime defaults
+     * @return a future that completes when the model switch is acknowledged
+     * @throws IllegalStateException
+     *             if this session has been terminated
+     * @since 1.3.0
+     */
+    public CompletableFuture<Void> setModel(String model, String reasoningEffort, String reasoningSummary,
+            com.github.copilot.rpc.ModelCapabilitiesOverride modelCapabilities) {
         ensureNotTerminated();
         ModelCapabilitiesOverride generatedCapabilities = null;
         if (modelCapabilities != null) {
@@ -1744,10 +1774,11 @@ public CompletableFuture<Void> setModel(String model, String reasoningEffort,
             }
             generatedCapabilities = new ModelCapabilitiesOverride(supports, limits);
         }
-        return getRpc().model
-                .switchTo(
-                        new SessionModelSwitchToParams(sessionId, model, reasoningEffort, null, generatedCapabilities))
-                .thenApply(r -> null);
+        var generatedReasoningSummary = reasoningSummary == null
+                ? null
+                : com.github.copilot.generated.rpc.ReasoningSummary.fromValue(reasoningSummary);
+        return getRpc().model.switchTo(new SessionModelSwitchToParams(sessionId, model, reasoningEffort,
+                generatedReasoningSummary, generatedCapabilities)).thenApply(r -> null);
     }
 
     /**
diff --git a/src/main/java/com/github/copilot/InternalExecutorProvider.java b/src/main/java/com/github/copilot/InternalExecutorProvider.java
new file mode 100644
index 0000000000..284965513a
--- /dev/null
+++ b/src/main/java/com/github/copilot/InternalExecutorProvider.java
@@ -0,0 +1,60 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *--------------------------------------------------------------------------------------------*/
+
+package com.github.copilot;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.ForkJoinPool;
+
+/**
+ * Resolves the {@link Executor} used by {@link CopilotClient} for internal
+ * asynchronous work.
+ *
+ * <p>
+ * This is the <strong>baseline (JDK 17+) implementation</strong>. When no
+ * user-provided executor is supplied, it falls back to
+ * {@link ForkJoinPool#commonPool()}, which is shared with the rest of the JVM
+ * and therefore never owned by the SDK.
+ *
+ * <p>
+ * <strong>Multi-release JAR contract.</strong> This class has a sibling variant
+ * at {@code src/main/java25/com/github/copilot/InternalExecutorProvider.java}
+ * that is compiled with {@code --release 25} into {@code META-INF/versions/25/}
+ * and selected automatically by the JVM on JDK 25+. Any change to the
+ * package-private surface of this class
+ * ({@link #InternalExecutorProvider(Executor) constructor}, {@link #get()},
+ * {@link #canBeShutdown()}) <strong>must be mirrored in both source
+ * trees</strong>. The two implementations must remain behaviourally
+ * interchangeable from the caller's perspective; only the default-executor
+ * strategy and ownership semantics differ.
+ *
+ * @implNote Maintainers: when editing this file, also edit
+ *           {@code src/main/java25/com/github/copilot/InternalExecutorProvider.java}.
+ *           The packaged JAR is verified at build time (see the
+ *           {@code java25-multi-release} profile in {@code pom.xml}) to ensure
+ *           the JDK 25 overlay is present.
+ */
+final class InternalExecutorProvider {
+
+    private final Executor executor;
+
+    InternalExecutorProvider(Executor userProvided) {
+        if (userProvided != null) {
+            this.executor = userProvided;
+        } else {
+            this.executor = ForkJoinPool.commonPool();
+        }
+    }
+
+    Executor get() {
+        return executor;
+    }
+
+    boolean canBeShutdown() {
+        // Since we are using ForkJoinPool.commonPool() or user provided only,
+        // we should not attempt to shut it down
+        return false;
+    }
+
+}
diff --git a/src/main/java/com/github/copilot/SessionRequestBuilder.java b/src/main/java/com/github/copilot/SessionRequestBuilder.java
index d9ad69282d..52f4e21797 100644
--- a/src/main/java/com/github/copilot/SessionRequestBuilder.java
+++ b/src/main/java/com/github/copilot/SessionRequestBuilder.java
@@ -106,6 +106,7 @@ static CreateSessionRequest buildCreateRequest(SessionConfig config, String sess
         request.setModel(config.getModel());
         request.setClientName(config.getClientName());
         request.setReasoningEffort(config.getReasoningEffort());
+        request.setReasoningSummary(config.getReasoningSummary());
         request.setTools(config.getTools());
         request.setSystemMessage(config.getSystemMessage());
         request.setAvailableTools(config.getAvailableTools());
@@ -124,14 +125,17 @@ static CreateSessionRequest buildCreateRequest(SessionConfig config, String sess
         }
         config.getIncludeSubAgentStreamingEvents().ifPresent(request::setIncludeSubAgentStreamingEvents);
         request.setMcpServers(config.getMcpServers());
+        request.setMcpOAuthTokenStorage(config.getMcpOAuthTokenStorage());
         request.setCustomAgents(config.getCustomAgents());
         request.setDefaultAgent(config.getDefaultAgent());
         request.setAgent(config.getAgent());
         request.setInfiniteSessions(config.getInfiniteSessions());
         request.setSkillDirectories(config.getSkillDirectories());
         request.setInstructionDirectories(config.getInstructionDirectories());
+        request.setPluginDirectories(config.getPluginDirectories());
+        request.setLargeOutput(config.getLargeOutput());
         request.setDisabledSkills(config.getDisabledSkills());
-        request.setConfigDir(config.getConfigDir());
+        request.setConfigDirectory(config.getConfigDirectory());
         config.getEnableConfigDiscovery().ifPresent(request::setEnableConfigDiscovery);
         request.setModelCapabilities(config.getModelCapabilities());
 
@@ -144,6 +148,9 @@ static CreateSessionRequest buildCreateRequest(SessionConfig config, String sess
         if (config.getOnElicitationRequest() != null) {
             request.setRequestElicitation(true);
         }
+        if (config.isEnableMcpApps()) {
+            request.setRequestMcpApps(true);
+        }
         if (config.getOnExitPlanMode() != null) {
             request.setRequestExitPlanMode(true);
         }
@@ -197,6 +204,7 @@ static ResumeSessionRequest buildResumeRequest(String sessionId, ResumeSessionCo
         request.setModel(config.getModel());
         request.setClientName(config.getClientName());
         request.setReasoningEffort(config.getReasoningEffort());
+        request.setReasoningSummary(config.getReasoningSummary());
         request.setTools(config.getTools());
         request.setSystemMessage(config.getSystemMessage());
         request.setAvailableTools(config.getAvailableTools());
@@ -210,7 +218,7 @@ static ResumeSessionRequest buildResumeRequest(String sessionId, ResumeSessionCo
             request.setHooks(true);
         }
         request.setWorkingDirectory(config.getWorkingDirectory());
-        request.setConfigDir(config.getConfigDir());
+        request.setConfigDirectory(config.getConfigDirectory());
         config.getEnableConfigDiscovery().ifPresent(request::setEnableConfigDiscovery);
         if (config.isDisableResume()) {
             request.setDisableResume(true);
@@ -220,11 +228,14 @@ static ResumeSessionRequest buildResumeRequest(String sessionId, ResumeSessionCo
         }
         config.getIncludeSubAgentStreamingEvents().ifPresent(request::setIncludeSubAgentStreamingEvents);
         request.setMcpServers(config.getMcpServers());
+        request.setMcpOAuthTokenStorage(config.getMcpOAuthTokenStorage());
         request.setCustomAgents(config.getCustomAgents());
         request.setDefaultAgent(config.getDefaultAgent());
         request.setAgent(config.getAgent());
         request.setSkillDirectories(config.getSkillDirectories());
         request.setInstructionDirectories(config.getInstructionDirectories());
+        request.setPluginDirectories(config.getPluginDirectories());
+        request.setLargeOutput(config.getLargeOutput());
         request.setDisabledSkills(config.getDisabledSkills());
         request.setInfiniteSessions(config.getInfiniteSessions());
         request.setModelCapabilities(config.getModelCapabilities());
@@ -238,6 +249,9 @@ static ResumeSessionRequest buildResumeRequest(String sessionId, ResumeSessionCo
         if (config.getOnElicitationRequest() != null) {
             request.setRequestElicitation(true);
         }
+        if (config.isEnableMcpApps()) {
+            request.setRequestMcpApps(true);
+        }
         if (config.getOnExitPlanMode() != null) {
             request.setRequestExitPlanMode(true);
         }
diff --git a/src/main/java/com/github/copilot/rpc/CopilotClientOptions.java b/src/main/java/com/github/copilot/rpc/CopilotClientOptions.java
index 69464aa724..9414670597 100644
--- a/src/main/java/com/github/copilot/rpc/CopilotClientOptions.java
+++ b/src/main/java/com/github/copilot/rpc/CopilotClientOptions.java
@@ -288,9 +288,11 @@ public CopilotClientOptions setEnvironment(Map<String, String> environment) {
 
     /**
      * Gets the executor used for internal asynchronous operations.
+     * <p>
+     * Returns {@code null} if no executor has been explicitly set, indicating that
+     * the SDK should use its default executor strategy.
      *
-     * @return the executor, or {@code null} to use the default
-     *         {@code ForkJoinPool.commonPool()}
+     * @return the executor, or {@code null} if using SDK defaults
      */
     public Executor getExecutor() {
         return executor;
@@ -300,15 +302,18 @@ public Executor getExecutor() {
      * Sets the executor used for internal asynchronous operations.
      * <p>
      * When provided, the SDK uses this executor for all internal
-     * {@code CompletableFuture} combinators instead of the default
-     * {@code ForkJoinPool.commonPool()}. This allows callers to isolate SDK work
-     * onto a dedicated thread pool or integrate with container-managed threading.
+     * {@code CompletableFuture} combinators. This allows callers to isolate SDK
+     * work onto a dedicated thread pool or integrate with container-managed
+     * threading.
      * <p>
-     * Passing {@code null} reverts to the default {@code ForkJoinPool.commonPool()}
-     * behavior.
+     * The SDK will not shut down a user-provided executor. If you pass a custom
+     * {@code ExecutorService}, you remain responsible for shutting it down.
+     * <p>
+     * If not set (or set to {@code null}), the SDK uses its default executor:
+     * virtual threads on JDK 25+, {@code ForkJoinPool.commonPool()} on older JDKs.
      *
      * @param executor
-     *            the executor to use, or {@code null} for the default
+     *            the executor to use, or {@code null} for SDK defaults
      * @return this options instance for fluent chaining
      */
     public CopilotClientOptions setExecutor(Executor executor) {
diff --git a/src/main/java/com/github/copilot/rpc/CreateSessionRequest.java b/src/main/java/com/github/copilot/rpc/CreateSessionRequest.java
index 1354e8c336..b8dddbec77 100644
--- a/src/main/java/com/github/copilot/rpc/CreateSessionRequest.java
+++ b/src/main/java/com/github/copilot/rpc/CreateSessionRequest.java
@@ -36,6 +36,9 @@ public final class CreateSessionRequest {
     @JsonProperty("reasoningEffort")
     private String reasoningEffort;
 
+    @JsonProperty("reasoningSummary")
+    private String reasoningSummary;
+
     @JsonProperty("tools")
     private List<ToolDefinition> tools;
 
@@ -78,6 +81,9 @@ public final class CreateSessionRequest {
     @JsonProperty("mcpServers")
     private Map<String, McpServerConfig> mcpServers;
 
+    @JsonProperty("mcpOAuthTokenStorage")
+    private String mcpOAuthTokenStorage;
+
     @JsonProperty("envValueMode")
     private String envValueMode;
 
@@ -99,11 +105,17 @@ public final class CreateSessionRequest {
     @JsonProperty("instructionDirectories")
     private List<String> instructionDirectories;
 
+    @JsonProperty("pluginDirectories")
+    private List<String> pluginDirectories;
+
+    @JsonProperty("largeOutput")
+    private LargeToolOutputConfig largeOutput;
+
     @JsonProperty("disabledSkills")
     private List<String> disabledSkills;
 
     @JsonProperty("configDir")
-    private String configDir;
+    private String configDirectory;
 
     @JsonProperty("enableConfigDiscovery")
     private Boolean enableConfigDiscovery;
@@ -114,6 +126,9 @@ public final class CreateSessionRequest {
     @JsonProperty("requestElicitation")
     private Boolean requestElicitation;
 
+    @JsonProperty("requestMcpApps")
+    private Boolean requestMcpApps;
+
     @JsonProperty("requestExitPlanMode")
     private Boolean requestExitPlanMode;
 
@@ -174,6 +189,19 @@ public void setReasoningEffort(String reasoningEffort) {
         this.reasoningEffort = reasoningEffort;
     }
 
+    /** Gets the reasoning summary mode. @return the reasoning summary mode */
+    public String getReasoningSummary() {
+        return reasoningSummary;
+    }
+
+    /**
+     * Sets the reasoning summary mode. @param reasoningSummary the reasoning
+     * summary mode
+     */
+    public void setReasoningSummary(String reasoningSummary) {
+        this.reasoningSummary = reasoningSummary;
+    }
+
     /** Gets the tools. @return the tool definitions */
     public List<ToolDefinition> getTools() {
         return tools == null ? null : Collections.unmodifiableList(tools);
@@ -344,6 +372,19 @@ public void setMcpServers(Map<String, McpServerConfig> mcpServers) {
         this.mcpServers = mcpServers;
     }
 
+    /** Gets MCP OAuth token storage mode. @return the storage mode */
+    public String getMcpOAuthTokenStorage() {
+        return mcpOAuthTokenStorage;
+    }
+
+    /**
+     * Sets MCP OAuth token storage mode. @param mcpOAuthTokenStorage the storage
+     * mode
+     */
+    public void setMcpOAuthTokenStorage(String mcpOAuthTokenStorage) {
+        this.mcpOAuthTokenStorage = mcpOAuthTokenStorage;
+    }
+
     /** Gets MCP environment variable value mode. @return the mode */
     public String getEnvValueMode() {
         return envValueMode;
@@ -418,6 +459,26 @@ public void setInstructionDirectories(List<String> instructionDirectories) {
         this.instructionDirectories = instructionDirectories;
     }
 
+    /** Gets plugin directories. @return the plugin directories */
+    public List<String> getPluginDirectories() {
+        return pluginDirectories == null ? null : Collections.unmodifiableList(pluginDirectories);
+    }
+
+    /** Sets plugin directories. @param pluginDirectories the directories */
+    public void setPluginDirectories(List<String> pluginDirectories) {
+        this.pluginDirectories = pluginDirectories;
+    }
+
+    /** Gets large output config. @return the large output config */
+    public LargeToolOutputConfig getLargeOutput() {
+        return largeOutput;
+    }
+
+    /** Sets large output config. @param largeOutput the large output config */
+    public void setLargeOutput(LargeToolOutputConfig largeOutput) {
+        this.largeOutput = largeOutput;
+    }
+
     /** Gets disabled skills. @return the disabled skill names */
     public List<String> getDisabledSkills() {
         return disabledSkills == null ? null : Collections.unmodifiableList(disabledSkills);
@@ -429,13 +490,13 @@ public void setDisabledSkills(List<String> disabledSkills) {
     }
 
     /** Gets config directory. @return the config directory path */
-    public String getConfigDir() {
-        return configDir;
+    public String getConfigDirectory() {
+        return configDirectory;
     }
 
-    /** Sets config directory. @param configDir the config directory path */
-    public void setConfigDir(String configDir) {
-        this.configDir = configDir;
+    /** Sets config directory. @param configDirectory the config directory path */
+    public void setConfigDirectory(String configDirectory) {
+        this.configDirectory = configDirectory;
     }
 
     /** Gets enable config discovery flag. @return the flag */
@@ -503,6 +564,21 @@ public void clearRequestElicitation() {
         this.requestElicitation = null;
     }
 
+    /** Gets the requestMcpApps flag. @return the flag */
+    public Boolean getRequestMcpApps() {
+        return requestMcpApps;
+    }
+
+    /** Sets the requestMcpApps flag. @param requestMcpApps the flag */
+    public void setRequestMcpApps(boolean requestMcpApps) {
+        this.requestMcpApps = requestMcpApps;
+    }
+
+    /** Clears the requestMcpApps setting, reverting to the default behavior. */
+    public void clearRequestMcpApps() {
+        this.requestMcpApps = null;
+    }
+
     /** Gets the requestExitPlanMode flag. @return the flag */
     public Boolean getRequestExitPlanMode() {
         return requestExitPlanMode;
diff --git a/src/main/java/com/github/copilot/rpc/LargeToolOutputConfig.java b/src/main/java/com/github/copilot/rpc/LargeToolOutputConfig.java
new file mode 100644
index 0000000000..1694761e2b
--- /dev/null
+++ b/src/main/java/com/github/copilot/rpc/LargeToolOutputConfig.java
@@ -0,0 +1,91 @@
+package com.github.copilot.rpc;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+/**
+ * Configuration for large tool output handling.
+ * <p>
+ * When a tool produces output exceeding {@link #getMaxSizeBytes()}, the SDK
+ * writes the full output to a file in {@link #getOutputDirectory()} and returns
+ * a truncated preview to the model.
+ *
+ * @since 1.3.0
+ */
+@JsonInclude(JsonInclude.Include.NON_NULL)
+public class LargeToolOutputConfig {
+
+    @JsonProperty("enabled")
+    private Boolean enabled;
+
+    @JsonProperty("maxSizeBytes")
+    private Long maxSizeBytes;
+
+    @JsonProperty("outputDir")
+    private String outputDirectory;
+
+    /**
+     * Gets whether large tool output handling is enabled.
+     *
+     * @return {@code true} if enabled, {@code false} if disabled, {@code null} for
+     *         default
+     */
+    public Boolean getEnabled() {
+        return enabled;
+    }
+
+    /**
+     * Sets whether large tool output handling is enabled. Defaults to {@code true}
+     * when unset.
+     *
+     * @param enabled
+     *            {@code true} to enable, {@code false} to disable
+     * @return this config for method chaining
+     */
+    public LargeToolOutputConfig setEnabled(Boolean enabled) {
+        this.enabled = enabled;
+        return this;
+    }
+
+    /**
+     * Gets the maximum tool output size in bytes before it is redirected to a file.
+     *
+     * @return the maximum size in bytes, or {@code null} for default
+     */
+    public Long getMaxSizeBytes() {
+        return maxSizeBytes;
+    }
+
+    /**
+     * Sets the maximum tool output size in bytes before it is redirected to a file.
+     *
+     * @param maxSizeBytes
+     *            the maximum size in bytes
+     * @return this config for method chaining
+     */
+    public LargeToolOutputConfig setMaxSizeBytes(Long maxSizeBytes) {
+        this.maxSizeBytes = maxSizeBytes;
+        return this;
+    }
+
+    /**
+     * Gets the directory where large tool output files are written.
+     *
+     * @return the output directory path, or {@code null} for default
+     */
+    public String getOutputDirectory() {
+        return outputDirectory;
+    }
+
+    /**
+     * Sets the directory where large tool output files are written.
+     *
+     * @param outputDirectory
+     *            the output directory path
+     * @return this config for method chaining
+     */
+    public LargeToolOutputConfig setOutputDirectory(String outputDirectory) {
+        this.outputDirectory = outputDirectory;
+        return this;
+    }
+}
diff --git a/src/main/java/com/github/copilot/rpc/MessageOptions.java b/src/main/java/com/github/copilot/rpc/MessageOptions.java
index a6cd02b0a7..c781011ff8 100644
--- a/src/main/java/com/github/copilot/rpc/MessageOptions.java
+++ b/src/main/java/com/github/copilot/rpc/MessageOptions.java
@@ -47,6 +47,7 @@ public class MessageOptions {
     private String mode;
     private AgentMode agentMode;
     private Map<String, String> requestHeaders;
+    private String displayPrompt;
 
     /**
      * Gets the message prompt.
@@ -176,6 +177,30 @@ public MessageOptions setRequestHeaders(Map<String, String> requestHeaders) {
         return this;
     }
 
+    /**
+     * Gets the display prompt shown in the timeline instead of the prompt.
+     *
+     * @return the display prompt, or {@code null} if not set
+     */
+    public String getDisplayPrompt() {
+        return displayPrompt;
+    }
+
+    /**
+     * Sets the display prompt shown in the timeline instead of the prompt.
+     * <p>
+     * If provided, this text is displayed in the conversation timeline UI instead
+     * of the actual prompt text.
+     *
+     * @param displayPrompt
+     *            the display prompt text
+     * @return this options instance for method chaining
+     */
+    public MessageOptions setDisplayPrompt(String displayPrompt) {
+        this.displayPrompt = displayPrompt;
+        return this;
+    }
+
     /**
      * Creates a shallow clone of this {@code MessageOptions} instance.
      * <p>
@@ -194,6 +219,7 @@ public MessageOptions clone() {
         copy.mode = this.mode;
         copy.agentMode = this.agentMode;
         copy.requestHeaders = this.requestHeaders != null ? new HashMap<>(this.requestHeaders) : null;
+        copy.displayPrompt = this.displayPrompt;
         return copy;
     }
 
diff --git a/src/main/java/com/github/copilot/rpc/ResumeSessionConfig.java b/src/main/java/com/github/copilot/rpc/ResumeSessionConfig.java
index fa28258b37..3cdf191826 100644
--- a/src/main/java/com/github/copilot/rpc/ResumeSessionConfig.java
+++ b/src/main/java/com/github/copilot/rpc/ResumeSessionConfig.java
@@ -51,22 +51,26 @@ public class ResumeSessionConfig {
     private Boolean coauthorEnabled;
     private Boolean manageScheduleEnabled;
     private String reasoningEffort;
+    private String reasoningSummary;
     private ModelCapabilitiesOverride modelCapabilities;
     private PermissionHandler onPermissionRequest;
     private UserInputHandler onUserInputRequest;
     private SessionHooks hooks;
     private String workingDirectory;
-    private String configDir;
+    private String configDirectory;
     private Boolean enableConfigDiscovery;
     private boolean disableResume;
     private boolean streaming;
     private Boolean includeSubAgentStreamingEvents;
     private Map<String, McpServerConfig> mcpServers;
+    private String mcpOAuthTokenStorage;
     private List<CustomAgentConfig> customAgents;
     private DefaultAgentConfig defaultAgent;
     private String agent;
     private List<String> skillDirectories;
     private List<String> instructionDirectories;
+    private List<String> pluginDirectories;
+    private LargeToolOutputConfig largeOutput;
     private List<String> disabledSkills;
     private InfiniteSessionConfig infiniteSessions;
     private Consumer<SessionEvent> onEvent;
@@ -74,6 +78,7 @@ public class ResumeSessionConfig {
     private ElicitationHandler onElicitationRequest;
     private ExitPlanModeHandler onExitPlanMode;
     private AutoModeSwitchHandler onAutoModeSwitch;
+    private boolean enableMcpApps;
     private String gitHubToken;
     private String remoteSession;
 
@@ -468,6 +473,29 @@ public ResumeSessionConfig setReasoningEffort(String reasoningEffort) {
         return this;
     }
 
+    /**
+     * Gets the reasoning summary mode.
+     *
+     * @return the reasoning summary mode ("none", "concise", or "detailed")
+     */
+    public String getReasoningSummary() {
+        return reasoningSummary;
+    }
+
+    /**
+     * Sets the reasoning summary mode for models that support configurable
+     * reasoning summaries. Use {@code "none"} to suppress summary output regardless
+     * of whether reasoning is enabled.
+     *
+     * @param reasoningSummary
+     *            the reasoning summary mode
+     * @return this config for method chaining
+     */
+    public ResumeSessionConfig setReasoningSummary(String reasoningSummary) {
+        this.reasoningSummary = reasoningSummary;
+        return this;
+    }
+
     /**
      * Gets the permission request handler.
      *
@@ -560,8 +588,8 @@ public ResumeSessionConfig setWorkingDirectory(String workingDirectory) {
      *
      * @return the configuration directory path
      */
-    public String getConfigDir() {
-        return configDir;
+    public String getConfigDirectory() {
+        return configDirectory;
     }
 
     /**
@@ -569,12 +597,12 @@ public String getConfigDir() {
      * <p>
      * Override the default configuration directory location.
      *
-     * @param configDir
+     * @param configDirectory
      *            the configuration directory path
      * @return this config for method chaining
      */
-    public ResumeSessionConfig setConfigDir(String configDir) {
-        this.configDir = configDir;
+    public ResumeSessionConfig setConfigDirectory(String configDirectory) {
+        this.configDirectory = configDirectory;
         return this;
     }
 
@@ -740,6 +768,37 @@ public ResumeSessionConfig setMcpServers(Map<String, McpServerConfig> mcpServers
         return this;
     }
 
+    /**
+     * Gets the MCP OAuth token storage mode.
+     *
+     * @return the storage mode, or {@code null} if not set
+     */
+    public String getMcpOAuthTokenStorage() {
+        return mcpOAuthTokenStorage;
+    }
+
+    /**
+     * Sets the MCP OAuth token storage mode.
+     * <p>
+     * Controls how MCP OAuth tokens are stored for this session:
+     * <ul>
+     * <li>{@code "persistent"} — tokens are stored in the OS keychain (shared
+     * across sessions)</li>
+     * <li>{@code "in-memory"} — tokens are stored in memory and discarded when the
+     * session ends</li>
+     * </ul>
+     * If not set, the SDK defaults to {@code "in-memory"} for safe multitenant
+     * behavior.
+     *
+     * @param mcpOAuthTokenStorage
+     *            the storage mode
+     * @return this config for method chaining
+     */
+    public ResumeSessionConfig setMcpOAuthTokenStorage(String mcpOAuthTokenStorage) {
+        this.mcpOAuthTokenStorage = mcpOAuthTokenStorage;
+        return this;
+    }
+
     /**
      * Gets the custom agent configurations.
      *
@@ -852,6 +911,48 @@ public ResumeSessionConfig setInstructionDirectories(List<String> instructionDir
         return this;
     }
 
+    /**
+     * Gets the plugin directories to load Open Plugin definitions from.
+     *
+     * @return the list of plugin directory paths
+     */
+    public List<String> getPluginDirectories() {
+        return pluginDirectories == null ? null : Collections.unmodifiableList(pluginDirectories);
+    }
+
+    /**
+     * Sets the plugin directories to load Open Plugin definitions from.
+     *
+     * @param pluginDirectories
+     *            the list of plugin directory paths
+     * @return this config for method chaining
+     */
+    public ResumeSessionConfig setPluginDirectories(List<String> pluginDirectories) {
+        this.pluginDirectories = pluginDirectories;
+        return this;
+    }
+
+    /**
+     * Gets the configuration for large tool output handling.
+     *
+     * @return the large output config, or {@code null} for default
+     */
+    public LargeToolOutputConfig getLargeOutput() {
+        return largeOutput;
+    }
+
+    /**
+     * Sets the configuration for large tool output handling.
+     *
+     * @param largeOutput
+     *            the large output config
+     * @return this config for method chaining
+     */
+    public ResumeSessionConfig setLargeOutput(LargeToolOutputConfig largeOutput) {
+        this.largeOutput = largeOutput;
+        return this;
+    }
+
     /**
      * Gets the disabled skills.
      *
@@ -972,6 +1073,31 @@ public ResumeSessionConfig setOnElicitationRequest(ElicitationHandler onElicitat
         return this;
     }
 
+    /**
+     * Returns whether MCP Apps (SEP-1865) UI passthrough is enabled on resume.
+     *
+     * @return {@code true} if the consumer has opted into MCP Apps, otherwise
+     *         {@code false}
+     * @see #setEnableMcpApps(boolean)
+     */
+    public boolean isEnableMcpApps() {
+        return enableMcpApps;
+    }
+
+    /**
+     * Enables MCP Apps (SEP-1865) UI passthrough on the resumed session. See
+     * {@link SessionConfig#setEnableMcpApps(boolean)} for full semantics (runtime
+     * gate, capability inspection, renderer requirement).
+     *
+     * @param enableMcpApps
+     *            {@code true} to opt into MCP Apps support on resume
+     * @return this config for method chaining
+     */
+    public ResumeSessionConfig setEnableMcpApps(boolean enableMcpApps) {
+        this.enableMcpApps = enableMcpApps;
+        return this;
+    }
+
     /**
      * Gets the exit-plan-mode request handler.
      *
@@ -1104,12 +1230,13 @@ public ResumeSessionConfig clone() {
         copy.provider = this.provider;
         copy.enableSessionTelemetry = this.enableSessionTelemetry;
         copy.reasoningEffort = this.reasoningEffort;
+        copy.reasoningSummary = this.reasoningSummary;
         copy.modelCapabilities = this.modelCapabilities;
         copy.onPermissionRequest = this.onPermissionRequest;
         copy.onUserInputRequest = this.onUserInputRequest;
         copy.hooks = this.hooks;
         copy.workingDirectory = this.workingDirectory;
-        copy.configDir = this.configDir;
+        copy.configDirectory = this.configDirectory;
         copy.enableConfigDiscovery = this.enableConfigDiscovery;
         copy.disableResume = this.disableResume;
         copy.streaming = this.streaming;
@@ -1122,6 +1249,8 @@ public ResumeSessionConfig clone() {
         copy.instructionDirectories = this.instructionDirectories != null
                 ? new ArrayList<>(this.instructionDirectories)
                 : null;
+        copy.pluginDirectories = this.pluginDirectories != null ? new ArrayList<>(this.pluginDirectories) : null;
+        copy.largeOutput = this.largeOutput;
         copy.disabledSkills = this.disabledSkills != null ? new ArrayList<>(this.disabledSkills) : null;
         copy.infiniteSessions = this.infiniteSessions;
         copy.onEvent = this.onEvent;
@@ -1129,6 +1258,7 @@ public ResumeSessionConfig clone() {
         copy.onElicitationRequest = this.onElicitationRequest;
         copy.onExitPlanMode = this.onExitPlanMode;
         copy.onAutoModeSwitch = this.onAutoModeSwitch;
+        copy.enableMcpApps = this.enableMcpApps;
         copy.gitHubToken = this.gitHubToken;
         copy.remoteSession = this.remoteSession;
         return copy;
diff --git a/src/main/java/com/github/copilot/rpc/ResumeSessionRequest.java b/src/main/java/com/github/copilot/rpc/ResumeSessionRequest.java
index 4321a24aa3..5305639edc 100644
--- a/src/main/java/com/github/copilot/rpc/ResumeSessionRequest.java
+++ b/src/main/java/com/github/copilot/rpc/ResumeSessionRequest.java
@@ -38,6 +38,9 @@ public final class ResumeSessionRequest {
     @JsonProperty("reasoningEffort")
     private String reasoningEffort;
 
+    @JsonProperty("reasoningSummary")
+    private String reasoningSummary;
+
     @JsonProperty("tools")
     private List<ToolDefinition> tools;
 
@@ -72,7 +75,7 @@ public final class ResumeSessionRequest {
     private String workingDirectory;
 
     @JsonProperty("configDir")
-    private String configDir;
+    private String configDirectory;
 
     @JsonProperty("enableConfigDiscovery")
     private Boolean enableConfigDiscovery;
@@ -89,6 +92,9 @@ public final class ResumeSessionRequest {
     @JsonProperty("mcpServers")
     private Map<String, McpServerConfig> mcpServers;
 
+    @JsonProperty("mcpOAuthTokenStorage")
+    private String mcpOAuthTokenStorage;
+
     @JsonProperty("envValueMode")
     private String envValueMode;
 
@@ -107,6 +113,12 @@ public final class ResumeSessionRequest {
     @JsonProperty("instructionDirectories")
     private List<String> instructionDirectories;
 
+    @JsonProperty("pluginDirectories")
+    private List<String> pluginDirectories;
+
+    @JsonProperty("largeOutput")
+    private LargeToolOutputConfig largeOutput;
+
     @JsonProperty("disabledSkills")
     private List<String> disabledSkills;
 
@@ -119,6 +131,9 @@ public final class ResumeSessionRequest {
     @JsonProperty("requestElicitation")
     private Boolean requestElicitation;
 
+    @JsonProperty("requestMcpApps")
+    private Boolean requestMcpApps;
+
     @JsonProperty("requestExitPlanMode")
     private Boolean requestExitPlanMode;
 
@@ -176,6 +191,19 @@ public void setReasoningEffort(String reasoningEffort) {
         this.reasoningEffort = reasoningEffort;
     }
 
+    /** Gets the reasoning summary mode. @return the reasoning summary mode */
+    public String getReasoningSummary() {
+        return reasoningSummary;
+    }
+
+    /**
+     * Sets the reasoning summary mode. @param reasoningSummary the reasoning
+     * summary mode
+     */
+    public void setReasoningSummary(String reasoningSummary) {
+        this.reasoningSummary = reasoningSummary;
+    }
+
     /** Gets the tools. @return the tool definitions */
     public List<ToolDefinition> getTools() {
         return tools == null ? null : Collections.unmodifiableList(tools);
@@ -323,13 +351,13 @@ public void setWorkingDirectory(String workingDirectory) {
     }
 
     /** Gets config directory. @return the config directory */
-    public String getConfigDir() {
-        return configDir;
+    public String getConfigDirectory() {
+        return configDirectory;
     }
 
-    /** Sets config directory. @param configDir the config directory */
-    public void setConfigDir(String configDir) {
-        this.configDir = configDir;
+    /** Sets config directory. @param configDirectory the config directory */
+    public void setConfigDirectory(String configDirectory) {
+        this.configDirectory = configDirectory;
     }
 
     /** Gets enable config discovery flag. @return the flag */
@@ -414,6 +442,19 @@ public void setMcpServers(Map<String, McpServerConfig> mcpServers) {
         this.mcpServers = mcpServers;
     }
 
+    /** Gets MCP OAuth token storage mode. @return the storage mode */
+    public String getMcpOAuthTokenStorage() {
+        return mcpOAuthTokenStorage;
+    }
+
+    /**
+     * Sets MCP OAuth token storage mode. @param mcpOAuthTokenStorage the storage
+     * mode
+     */
+    public void setMcpOAuthTokenStorage(String mcpOAuthTokenStorage) {
+        this.mcpOAuthTokenStorage = mcpOAuthTokenStorage;
+    }
+
     /** Gets MCP environment variable value mode. @return the mode */
     public String getEnvValueMode() {
         return envValueMode;
@@ -478,6 +519,26 @@ public void setInstructionDirectories(List<String> instructionDirectories) {
         this.instructionDirectories = instructionDirectories;
     }
 
+    /** Gets plugin directories. @return the plugin directories */
+    public List<String> getPluginDirectories() {
+        return pluginDirectories == null ? null : Collections.unmodifiableList(pluginDirectories);
+    }
+
+    /** Sets plugin directories. @param pluginDirectories the directories */
+    public void setPluginDirectories(List<String> pluginDirectories) {
+        this.pluginDirectories = pluginDirectories;
+    }
+
+    /** Gets large output config. @return the large output config */
+    public LargeToolOutputConfig getLargeOutput() {
+        return largeOutput;
+    }
+
+    /** Sets large output config. @param largeOutput the large output config */
+    public void setLargeOutput(LargeToolOutputConfig largeOutput) {
+        this.largeOutput = largeOutput;
+    }
+
     /** Gets disabled skills. @return the disabled skill names */
     public List<String> getDisabledSkills() {
         return disabledSkills == null ? null : Collections.unmodifiableList(disabledSkills);
@@ -528,6 +589,21 @@ public void clearRequestElicitation() {
         this.requestElicitation = null;
     }
 
+    /** Gets the requestMcpApps flag. @return the flag */
+    public Boolean getRequestMcpApps() {
+        return requestMcpApps;
+    }
+
+    /** Sets the requestMcpApps flag. @param requestMcpApps the flag */
+    public void setRequestMcpApps(boolean requestMcpApps) {
+        this.requestMcpApps = requestMcpApps;
+    }
+
+    /** Clears the requestMcpApps setting, reverting to the default behavior. */
+    public void clearRequestMcpApps() {
+        this.requestMcpApps = null;
+    }
+
     /** Gets the requestExitPlanMode flag. @return the flag */
     public Boolean getRequestExitPlanMode() {
         return requestExitPlanMode;
diff --git a/src/main/java/com/github/copilot/rpc/SendMessageRequest.java b/src/main/java/com/github/copilot/rpc/SendMessageRequest.java
index b73d2caa22..c87dda7623 100644
--- a/src/main/java/com/github/copilot/rpc/SendMessageRequest.java
+++ b/src/main/java/com/github/copilot/rpc/SendMessageRequest.java
@@ -43,6 +43,9 @@ public final class SendMessageRequest {
     @JsonProperty("requestHeaders")
     private Map<String, String> requestHeaders;
 
+    @JsonProperty("displayPrompt")
+    private String displayPrompt;
+
     /** Gets the session ID. @return the session ID */
     public String getSessionId() {
         return sessionId;
@@ -102,4 +105,19 @@ public Map<String, String> getRequestHeaders() {
     public void setRequestHeaders(Map<String, String> requestHeaders) {
         this.requestHeaders = requestHeaders;
     }
+
+    /** Gets the display prompt. @return the display prompt */
+    public String getDisplayPrompt() {
+        return displayPrompt;
+    }
+
+    /**
+     * Sets the display prompt shown in the timeline instead of the prompt.
+     *
+     * @param displayPrompt
+     *            the display prompt
+     */
+    public void setDisplayPrompt(String displayPrompt) {
+        this.displayPrompt = displayPrompt;
+    }
 }
diff --git a/src/main/java/com/github/copilot/rpc/SessionConfig.java b/src/main/java/com/github/copilot/rpc/SessionConfig.java
index 2a42df6108..c845306879 100644
--- a/src/main/java/com/github/copilot/rpc/SessionConfig.java
+++ b/src/main/java/com/github/copilot/rpc/SessionConfig.java
@@ -42,6 +42,7 @@ public class SessionConfig {
     private String clientName;
     private String model;
     private String reasoningEffort;
+    private String reasoningSummary;
     private List<ToolDefinition> tools;
     private SystemMessageConfig systemMessage;
     private List<String> availableTools;
@@ -59,14 +60,17 @@ public class SessionConfig {
     private boolean streaming;
     private Boolean includeSubAgentStreamingEvents;
     private Map<String, McpServerConfig> mcpServers;
+    private String mcpOAuthTokenStorage;
     private List<CustomAgentConfig> customAgents;
     private DefaultAgentConfig defaultAgent;
     private String agent;
     private InfiniteSessionConfig infiniteSessions;
     private List<String> skillDirectories;
     private List<String> instructionDirectories;
+    private List<String> pluginDirectories;
+    private LargeToolOutputConfig largeOutput;
     private List<String> disabledSkills;
-    private String configDir;
+    private String configDirectory;
     private Boolean enableConfigDiscovery;
     private ModelCapabilitiesOverride modelCapabilities;
     private Consumer<SessionEvent> onEvent;
@@ -74,6 +78,7 @@ public class SessionConfig {
     private ElicitationHandler onElicitationRequest;
     private ExitPlanModeHandler onExitPlanMode;
     private AutoModeSwitchHandler onAutoModeSwitch;
+    private boolean enableMcpApps;
     private String gitHubToken;
     private String remoteSession;
     private CloudSessionOptions cloud;
@@ -171,6 +176,29 @@ public SessionConfig setReasoningEffort(String reasoningEffort) {
         return this;
     }
 
+    /**
+     * Gets the reasoning summary mode.
+     *
+     * @return the reasoning summary mode ("none", "concise", or "detailed")
+     */
+    public String getReasoningSummary() {
+        return reasoningSummary;
+    }
+
+    /**
+     * Sets the reasoning summary mode for models that support configurable
+     * reasoning summaries. Use {@code "none"} to suppress summary output regardless
+     * of whether reasoning is enabled.
+     *
+     * @param reasoningSummary
+     *            the reasoning summary mode
+     * @return this config instance for method chaining
+     */
+    public SessionConfig setReasoningSummary(String reasoningSummary) {
+        this.reasoningSummary = reasoningSummary;
+        return this;
+    }
+
     /**
      * Gets the custom tools for this session.
      *
@@ -650,6 +678,37 @@ public SessionConfig setMcpServers(Map<String, McpServerConfig> mcpServers) {
         return this;
     }
 
+    /**
+     * Gets the MCP OAuth token storage mode.
+     *
+     * @return the storage mode, or {@code null} if not set
+     */
+    public String getMcpOAuthTokenStorage() {
+        return mcpOAuthTokenStorage;
+    }
+
+    /**
+     * Sets the MCP OAuth token storage mode.
+     * <p>
+     * Controls how MCP OAuth tokens are stored for this session:
+     * <ul>
+     * <li>{@code "persistent"} — tokens are stored in the OS keychain (shared
+     * across sessions)</li>
+     * <li>{@code "in-memory"} — tokens are stored in memory and discarded when the
+     * session ends</li>
+     * </ul>
+     * If not set, the SDK defaults to {@code "in-memory"} for safe multitenant
+     * behavior.
+     *
+     * @param mcpOAuthTokenStorage
+     *            the storage mode
+     * @return this config instance for method chaining
+     */
+    public SessionConfig setMcpOAuthTokenStorage(String mcpOAuthTokenStorage) {
+        this.mcpOAuthTokenStorage = mcpOAuthTokenStorage;
+        return this;
+    }
+
     /**
      * Gets the custom agent configurations.
      *
@@ -796,6 +855,48 @@ public SessionConfig setInstructionDirectories(List<String> instructionDirectori
         return this;
     }
 
+    /**
+     * Gets the plugin directories to load Open Plugin definitions from.
+     *
+     * @return the list of plugin directory paths
+     */
+    public List<String> getPluginDirectories() {
+        return pluginDirectories == null ? null : Collections.unmodifiableList(pluginDirectories);
+    }
+
+    /**
+     * Sets the plugin directories to load Open Plugin definitions from.
+     *
+     * @param pluginDirectories
+     *            the list of plugin directory paths
+     * @return this config instance for method chaining
+     */
+    public SessionConfig setPluginDirectories(List<String> pluginDirectories) {
+        this.pluginDirectories = pluginDirectories;
+        return this;
+    }
+
+    /**
+     * Gets the configuration for large tool output handling.
+     *
+     * @return the large output config, or {@code null} for default
+     */
+    public LargeToolOutputConfig getLargeOutput() {
+        return largeOutput;
+    }
+
+    /**
+     * Sets the configuration for large tool output handling.
+     *
+     * @param largeOutput
+     *            the large output config
+     * @return this config instance for method chaining
+     */
+    public SessionConfig setLargeOutput(LargeToolOutputConfig largeOutput) {
+        this.largeOutput = largeOutput;
+        return this;
+    }
+
     /**
      * Gets the disabled skill names.
      *
@@ -825,8 +926,8 @@ public SessionConfig setDisabledSkills(List<String> disabledSkills) {
      *
      * @return the config directory path
      */
-    public String getConfigDir() {
-        return configDir;
+    public String getConfigDirectory() {
+        return configDirectory;
     }
 
     /**
@@ -835,12 +936,12 @@ public String getConfigDir() {
      * This allows using a specific directory for session configuration instead of
      * the default location.
      *
-     * @param configDir
+     * @param configDirectory
      *            the configuration directory path
      * @return this config instance for method chaining
      */
-    public SessionConfig setConfigDir(String configDir) {
-        this.configDir = configDir;
+    public SessionConfig setConfigDirectory(String configDirectory) {
+        this.configDirectory = configDirectory;
         return this;
     }
 
@@ -1033,6 +1134,49 @@ public SessionConfig setOnElicitationRequest(ElicitationHandler onElicitationReq
         return this;
     }
 
+    /**
+     * Returns whether MCP Apps (SEP-1865) UI passthrough is enabled on this
+     * session.
+     *
+     * @return {@code true} if the consumer has opted into MCP Apps, otherwise
+     *         {@code false}
+     * @see #setEnableMcpApps(boolean)
+     */
+    public boolean isEnableMcpApps() {
+        return enableMcpApps;
+    }
+
+    /**
+     * Enables MCP Apps (SEP-1865) UI passthrough on this session.
+     * <p>
+     * When {@code true} <b>and</b> the runtime has MCP Apps enabled (via the
+     * {@code MCP_APPS} feature flag or {@code COPILOT_MCP_APPS=true} environment
+     * override), the runtime adds the {@code mcp-apps} capability to the session,
+     * which causes it to advertise the
+     * {@code extensions.io.modelcontextprotocol/ui} extension to MCP servers (so
+     * they expose {@code _meta.ui.resourceUri} on tools) and to expose the
+     * {@code session.rpc.mcp.apps.{listTools,callTool,readResource,
+     * setHostContext,getHostContext,diagnose}} JSON-RPC methods.
+     * <p>
+     * If the runtime gate is off, the opt-in is silently dropped server-side (the
+     * runtime logs a warning); the session is created normally but the MCP Apps
+     * surface is unavailable. Inspect {@link SessionUiCapabilities#getMcpApps()} on
+     * {@link com.github.copilot.CopilotSession#getCapabilities()} to detect this.
+     * <p>
+     * SDK consumers MUST set this to {@code true} only when they have an iframe
+     * renderer that can display {@code ui://} MCP App bundles. Setting it without a
+     * renderer will cause MCP servers to register UI-enabled tool variants the
+     * consumer cannot display.
+     *
+     * @param enableMcpApps
+     *            {@code true} to opt into MCP Apps support
+     * @return this config instance for method chaining
+     */
+    public SessionConfig setEnableMcpApps(boolean enableMcpApps) {
+        this.enableMcpApps = enableMcpApps;
+        return this;
+    }
+
     /**
      * Gets the exit-plan-mode request handler.
      *
@@ -1200,6 +1344,7 @@ public SessionConfig clone() {
         copy.clientName = this.clientName;
         copy.model = this.model;
         copy.reasoningEffort = this.reasoningEffort;
+        copy.reasoningSummary = this.reasoningSummary;
         copy.tools = this.tools != null ? new ArrayList<>(this.tools) : null;
         copy.systemMessage = this.systemMessage;
         copy.availableTools = this.availableTools != null ? new ArrayList<>(this.availableTools) : null;
@@ -1225,8 +1370,10 @@ public SessionConfig clone() {
         copy.instructionDirectories = this.instructionDirectories != null
                 ? new ArrayList<>(this.instructionDirectories)
                 : null;
+        copy.pluginDirectories = this.pluginDirectories != null ? new ArrayList<>(this.pluginDirectories) : null;
+        copy.largeOutput = this.largeOutput;
         copy.disabledSkills = this.disabledSkills != null ? new ArrayList<>(this.disabledSkills) : null;
-        copy.configDir = this.configDir;
+        copy.configDirectory = this.configDirectory;
         copy.enableConfigDiscovery = this.enableConfigDiscovery;
         copy.modelCapabilities = this.modelCapabilities;
         copy.onEvent = this.onEvent;
@@ -1234,6 +1381,7 @@ public SessionConfig clone() {
         copy.onElicitationRequest = this.onElicitationRequest;
         copy.onExitPlanMode = this.onExitPlanMode;
         copy.onAutoModeSwitch = this.onAutoModeSwitch;
+        copy.enableMcpApps = this.enableMcpApps;
         copy.gitHubToken = this.gitHubToken;
         copy.remoteSession = this.remoteSession;
         copy.cloud = this.cloud;
diff --git a/src/main/java/com/github/copilot/rpc/SessionUiCapabilities.java b/src/main/java/com/github/copilot/rpc/SessionUiCapabilities.java
index 015220d0c1..1d3397c8f4 100644
--- a/src/main/java/com/github/copilot/rpc/SessionUiCapabilities.java
+++ b/src/main/java/com/github/copilot/rpc/SessionUiCapabilities.java
@@ -21,6 +21,9 @@ public class SessionUiCapabilities {
     @JsonProperty("elicitation")
     private Boolean elicitation;
 
+    @JsonProperty("mcpApps")
+    private Boolean mcpApps;
+
     /**
      * Returns whether the host supports interactive elicitation dialogs.
      *
@@ -53,4 +56,41 @@ public SessionUiCapabilities clearElicitation() {
         return this;
     }
 
+    /**
+     * Returns whether the runtime has accepted the session's MCP Apps (SEP-1865)
+     * opt-in. Present and {@code true} when the consumer set
+     * {@code enableMcpApps=true} on create/resume <b>and</b> the runtime's
+     * {@code MCP_APPS} feature flag (or {@code COPILOT_MCP_APPS=true} env override)
+     * is on. Otherwise empty or {@code false}, indicating the runtime silently
+     * dropped the opt-in.
+     *
+     * @return an {@link Optional} containing the boolean value, or empty if not set
+     */
+    @JsonIgnore
+    public Optional<Boolean> getMcpApps() {
+        return Optional.ofNullable(mcpApps);
+    }
+
+    /**
+     * Sets whether the runtime has accepted the MCP Apps opt-in.
+     *
+     * @param mcpApps
+     *            {@code true} if MCP Apps is enabled for this session
+     * @return this instance for method chaining
+     */
+    public SessionUiCapabilities setMcpApps(boolean mcpApps) {
+        this.mcpApps = mcpApps;
+        return this;
+    }
+
+    /**
+     * Clears the mcpApps setting.
+     *
+     * @return this instance for method chaining
+     */
+    public SessionUiCapabilities clearMcpApps() {
+        this.mcpApps = null;
+        return this;
+    }
+
 }
diff --git a/src/main/java25/com/github/copilot/InternalExecutorProvider.java b/src/main/java25/com/github/copilot/InternalExecutorProvider.java
new file mode 100644
index 0000000000..10878bb0c4
--- /dev/null
+++ b/src/main/java25/com/github/copilot/InternalExecutorProvider.java
@@ -0,0 +1,65 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *--------------------------------------------------------------------------------------------*/
+
+package com.github.copilot;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ForkJoinPool;
+
+/**
+ * Resolves the {@link Executor} used by {@link CopilotClient} for internal
+ * asynchronous work.
+ *
+ * <p>This is the <strong>JDK 25+ multi-release variant</strong>. It is
+ * compiled with {@code --release 25} into
+ * {@code META-INF/versions/25/com/github/copilot/InternalExecutorProvider.class}
+ * inside the packaged JAR and is automatically loaded in preference to the
+ * baseline class when the JVM runtime feature version is 25 or greater.
+ * When no user-provided executor is supplied, it creates an SDK-owned
+ * {@link Executors#newVirtualThreadPerTaskExecutor() virtual-thread executor}
+ * that is shut down by {@link CopilotClient#close()}.
+ *
+ * <p><strong>Multi-release JAR contract.</strong> This class is the
+ * JDK 25 sibling of the baseline implementation at
+ * {@code src/main/java/com/github/copilot/InternalExecutorProvider.java}.
+ * The package-private surface of both classes
+ * ({@link #InternalExecutorProvider(Executor) constructor},
+ * {@link #get()}, {@link #canBeShutdown()}) <strong>must be kept in
+ * lock-step</strong>; only the default-executor strategy and ownership
+ * semantics differ.
+ *
+ * @implNote
+ * Maintainers: when editing this file, also edit
+ * {@code src/main/java/com/github/copilot/InternalExecutorProvider.java}.
+ * The packaged JAR is verified at build time (see the
+ * {@code java25-multi-release} profile in {@code pom.xml}) to ensure this
+ * overlay class is present.
+ */
+final class InternalExecutorProvider {
+
+    private final Executor executor;
+    private final boolean owned;
+
+    InternalExecutorProvider(Executor userProvided) {
+        if (userProvided != null) {
+            this.executor = userProvided;
+            this.owned = false;
+        } else {
+            this.executor = Executors.newVirtualThreadPerTaskExecutor();
+            this.owned = true;
+        }
+    }
+
+    Executor get() {
+        return executor;
+    }
+
+    boolean canBeShutdown() {
+        // We can only shut down the executor if we created it (i.e., if it's owned) 
+        // such as when using Executors.newVirtualThreadPerTaskExecutor(), 
+        // which creates an executor that we are responsible for shutting down.
+        return owned;
+    }
+}
diff --git a/src/test/java/com/github/copilot/ConfigCloneTest.java b/src/test/java/com/github/copilot/ConfigCloneTest.java
index f26f67ed91..e40a3048b0 100644
--- a/src/test/java/com/github/copilot/ConfigCloneTest.java
+++ b/src/test/java/com/github/copilot/ConfigCloneTest.java
@@ -21,6 +21,7 @@
 import com.github.copilot.rpc.DefaultAgentConfig;
 import com.github.copilot.rpc.ExitPlanModeResult;
 import com.github.copilot.rpc.InfiniteSessionConfig;
+import com.github.copilot.rpc.LargeToolOutputConfig;
 import com.github.copilot.rpc.MessageOptions;
 import com.github.copilot.rpc.ModelInfo;
 import com.github.copilot.rpc.ResumeSessionConfig;
@@ -114,6 +115,10 @@ void sessionConfigCloneBasic() {
         original.setSessionId("my-session");
         original.setClientName("my-app");
         original.setModel("gpt-4o");
+        original.setReasoningSummary("detailed");
+        original.setPluginDirectories(List.of("/plugins/a", "/plugins/b"));
+        original.setLargeOutput(
+                new LargeToolOutputConfig().setEnabled(true).setMaxSizeBytes(1024L).setOutputDirectory("/tmp/out"));
         original.setStreaming(true);
 
         SessionConfig cloned = original.clone();
@@ -121,6 +126,9 @@ void sessionConfigCloneBasic() {
         assertEquals(original.getSessionId(), cloned.getSessionId());
         assertEquals(original.getClientName(), cloned.getClientName());
         assertEquals(original.getModel(), cloned.getModel());
+        assertEquals(original.getReasoningSummary(), cloned.getReasoningSummary());
+        assertEquals(original.getPluginDirectories(), cloned.getPluginDirectories());
+        assertEquals(original.getLargeOutput(), cloned.getLargeOutput());
         assertEquals(original.isStreaming(), cloned.isStreaming());
     }
 
@@ -162,11 +170,18 @@ void sessionConfigAgentAndOnEventCloned() {
     void resumeSessionConfigCloneBasic() {
         ResumeSessionConfig original = new ResumeSessionConfig();
         original.setModel("o1");
+        original.setReasoningSummary("none");
+        original.setPluginDirectories(List.of("/plugins/r"));
+        original.setLargeOutput(
+                new LargeToolOutputConfig().setEnabled(false).setMaxSizeBytes(2048L).setOutputDirectory("/tmp/resume"));
         original.setStreaming(false);
 
         ResumeSessionConfig cloned = original.clone();
 
         assertEquals(original.getModel(), cloned.getModel());
+        assertEquals(original.getReasoningSummary(), cloned.getReasoningSummary());
+        assertEquals(original.getPluginDirectories(), cloned.getPluginDirectories());
+        assertEquals(original.getLargeOutput(), cloned.getLargeOutput());
         assertEquals(original.isStreaming(), cloned.isStreaming());
     }
 
@@ -328,8 +343,8 @@ void resumeSessionConfigAllSetters() {
         config.setWorkingDirectory("/project/src");
         assertEquals("/project/src", config.getWorkingDirectory());
 
-        config.setConfigDir("/home/user/.config/copilot");
-        assertEquals("/home/user/.config/copilot", config.getConfigDir());
+        config.setConfigDirectory("/home/user/.config/copilot");
+        assertEquals("/home/user/.config/copilot", config.getConfigDirectory());
 
         config.setSkillDirectories(List.of("/skills/custom"));
         assertEquals(List.of("/skills/custom"), config.getSkillDirectories());
diff --git a/src/test/java/com/github/copilot/CopilotSessionTest.java b/src/test/java/com/github/copilot/CopilotSessionTest.java
index 9c74d49464..44a7373ec7 100644
--- a/src/test/java/com/github/copilot/CopilotSessionTest.java
+++ b/src/test/java/com/github/copilot/CopilotSessionTest.java
@@ -559,7 +559,7 @@ void testShouldCreateSessionWithCustomConfigDir() throws Exception {
             String customConfigDir = ctx.getWorkDir().resolve("custom-config").toString();
 
             SessionConfig config = new SessionConfig().setOnPermissionRequest(PermissionHandler.APPROVE_ALL)
-                    .setConfigDir(customConfigDir);
+                    .setConfigDirectory(customConfigDir);
             CopilotSession session = client.createSession(config).get();
 
             assertNotNull(session.getSessionId());
diff --git a/src/test/java/com/github/copilot/CreateSessionReKeyEntryTest.java b/src/test/java/com/github/copilot/CreateSessionReKeyEntryTest.java
index 94f4edbdf1..156c968489 100644
--- a/src/test/java/com/github/copilot/CreateSessionReKeyEntryTest.java
+++ b/src/test/java/com/github/copilot/CreateSessionReKeyEntryTest.java
@@ -25,8 +25,10 @@
 import com.github.copilot.rpc.SessionConfig;
 
 /**
- * Tests for the session-map re-key cleanup paths in CopilotClient when the
- * server returns a different session ID than the client-supplied one.
+ * Tests that CopilotClient rejects session.create responses whose sessionId
+ * differs from the client-supplied one. Re-keying the sessions map at runtime
+ * is intentionally not supported — the server must honor the client-supplied
+ * sessionId (or generate one when none is supplied).
  */
 class CreateSessionReKeyEntryTest {
 
@@ -177,7 +179,7 @@ private static void injectConnection(CopilotClient client, JsonRpcClient rpc) th
     }
 
     @Test
-    void createSessionReKeyEntry_successfulReKey_removesOldKeyAndAddsNewKey() throws Exception {
+    void createSession_serverReturnsDifferentSessionId_throwsAndRemovesPreRegisteredEntry() throws Exception {
         String clientSessionId = "client-supplied-id";
         String serverSessionId = "server-returned-id";
 
@@ -188,26 +190,26 @@ void createSessionReKeyEntry_successfulReKey_removesOldKeyAndAddsNewKey() throws
             var config = new SessionConfig().setSessionId(clientSessionId)
                     .setOnPermissionRequest(PermissionHandler.APPROVE_ALL);
 
-            CopilotSession session = client.createSession(config).get();
+            ExecutionException ex = assertThrows(ExecutionException.class, () -> client.createSession(config).get());
+            assertNotNull(ex.getCause());
+            assertTrue(ex.getCause().getMessage().contains(serverSessionId),
+                    "Error message should mention the server-returned sessionId");
+            assertTrue(ex.getCause().getMessage().contains(clientSessionId),
+                    "Error message should mention the client-requested sessionId");
 
             Map<String, CopilotSession> sessions = getSessionsMap(client);
-
-            // The old client-supplied key should be removed
             assertNull(sessions.get(clientSessionId),
-                    "Old client-supplied sessionId should be removed from sessions map after re-key");
-            // The new server-returned key should be present
-            assertSame(session, sessions.get(serverSessionId),
-                    "Server-returned sessionId should be the key in sessions map");
-            // The session object should report the server-returned ID
-            assertEquals(serverSessionId, session.getSessionId(),
-                    "Session should report the server-returned sessionId");
+                    "Pre-registered client-supplied sessionId should be removed after rejection");
+            assertNull(sessions.get(serverSessionId),
+                    "Server-returned sessionId should never be registered after rejection");
+            assertTrue(sessions.isEmpty(), "Sessions map should be empty after rejected create");
 
             client.close();
         }
     }
 
     @Test
-    void createSessionReKeyEntry_failureAfterReKey_removesBothKeys() throws Exception {
+    void createSession_serverReturnsDifferentSessionIdWithSkipCustomInstructions_throwsAndCleansUp() throws Exception {
         String clientSessionId = "client-supplied-id";
         String serverSessionId = "server-returned-id";
 
@@ -215,29 +217,27 @@ void createSessionReKeyEntry_failureAfterReKey_removesBothKeys() throws Exceptio
             var client = new CopilotClient(new CopilotClientOptions().setAutoStart(false));
             injectConnection(client, server.rpcClient);
 
-            // Set skipCustomInstructions so that session.options.update is actually invoked
+            // Even when skipCustomInstructions would trigger session.options.update,
+            // the sessionId-mismatch error fires first and short-circuits the flow.
             var config = new SessionConfig().setSessionId(clientSessionId)
                     .setOnPermissionRequest(PermissionHandler.APPROVE_ALL).setSkipCustomInstructions(true);
 
-            // The session.options.update will fail, triggering the exceptionally handler
             ExecutionException ex = assertThrows(ExecutionException.class, () -> client.createSession(config).get());
             assertNotNull(ex.getCause());
 
             Map<String, CopilotSession> sessions = getSessionsMap(client);
-
-            // Both the original and re-keyed entries should be cleaned up
             assertNull(sessions.get(clientSessionId),
-                    "Original client-supplied sessionId should be removed on failure");
+                    "Pre-registered client-supplied sessionId should be removed on failure");
             assertNull(sessions.get(serverSessionId),
-                    "Re-keyed server-returned sessionId should be removed on failure");
-            assertTrue(sessions.isEmpty(), "Sessions map should be empty after failed create with re-key");
+                    "Server-returned sessionId should never be registered on failure");
+            assertTrue(sessions.isEmpty(), "Sessions map should be empty after failed create");
 
             client.close();
         }
     }
 
     @Test
-    void createSessionReKeyEntry_noReKey_sameIdKept() throws Exception {
+    void createSession_serverReturnsSameSessionId_sessionKeptUnderClientId() throws Exception {
         String sessionId = "same-id-for-both";
 
         try (var server = new ReKeyServer(sessionId, false)) {
diff --git a/src/test/java/com/github/copilot/InternalExecutorProviderIT.java b/src/test/java/com/github/copilot/InternalExecutorProviderIT.java
new file mode 100644
index 0000000000..1cc6b482e8
--- /dev/null
+++ b/src/test/java/com/github/copilot/InternalExecutorProviderIT.java
@@ -0,0 +1,108 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *--------------------------------------------------------------------------------------------*/
+
+package com.github.copilot;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.File;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.TimeUnit;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * Failsafe integration test that asserts the multi-release behaviour of
+ * {@link InternalExecutorProvider} against the actually packaged JAR.
+ * <p>
+ * Runs after {@code package}, when {@code target/${finalName}.jar} exists with
+ * its real {@code Multi-Release: true} manifest and (on JDK 25+ builds) the
+ * {@code META-INF/versions/25/} override produced by {@code maven-jar-plugin}.
+ * <p>
+ * The test spawns a child JVM with the packaged JAR plus {@code test-classes}
+ * on the classpath, runs {@link InternalExecutorProviderProbe}, and asserts
+ * that the executor selected for the current runtime matches expectations.
+ */
+class InternalExecutorProviderIT {
+
+    @Test
+    void packagedJarSelectsExecutorPerRuntimeVersion() throws Exception {
+        Path packagedJar = locatePackagedJar();
+        Path testClasses = locateTestClassesDir();
+        String javaBin = locateJavaBinary();
+
+        String classpath = packagedJar.toString() + File.pathSeparator + testClasses.toString();
+        Process process = new ProcessBuilder(javaBin, "-cp", classpath,
+                "com.github.copilot.InternalExecutorProviderProbe").redirectErrorStream(true).start();
+
+        String output;
+        try {
+            output = new String(process.getInputStream().readAllBytes(), StandardCharsets.UTF_8);
+            assertTrue(process.waitFor(30, TimeUnit.SECONDS), "Probe JVM did not exit within 30s. Output:\n" + output);
+        } finally {
+            if (process.isAlive()) {
+                process.destroyForcibly();
+            }
+        }
+
+        assertEquals(0, process.exitValue(), "Probe exited non-zero. Output:\n" + output);
+
+        Map<String, String> kv = parseKeyValues(output);
+        String featureRaw = kv.get("feature");
+        assertNotNull(featureRaw, "Probe did not report 'feature'. Output:\n" + output);
+        int feature = Integer.parseInt(featureRaw);
+
+        boolean expectOwnedVirtual = feature >= 25;
+        assertEquals(String.valueOf(expectOwnedVirtual), kv.get("canBeShutdown"),
+                "canBeShutdown mismatch for JDK feature=" + feature + ". Output:\n" + output);
+        assertEquals(String.valueOf(expectOwnedVirtual), kv.get("virtual"),
+                "virtual mismatch for JDK feature=" + feature + ". Output:\n" + output);
+    }
+
+    private static Path locatePackagedJar() {
+        String buildDir = System.getProperty("project.build.directory");
+        String finalName = System.getProperty("project.build.finalName");
+        assertNotNull(buildDir, "System property 'project.build.directory' must be set by failsafe");
+        assertNotNull(finalName, "System property 'project.build.finalName' must be set by failsafe");
+        Path jar = Path.of(buildDir, finalName + ".jar");
+        assertTrue(Files.isRegularFile(jar), "Packaged JAR must exist: " + jar);
+        return jar;
+    }
+
+    private static Path locateTestClassesDir() {
+        String testOutput = System.getProperty("project.build.testOutputDirectory");
+        assertNotNull(testOutput, "System property 'project.build.testOutputDirectory' must be set by failsafe");
+        Path dir = Path.of(testOutput);
+        assertTrue(Files.isDirectory(dir), "test-classes dir must exist: " + dir);
+        return dir;
+    }
+
+    private static String locateJavaBinary() {
+        Path javaHome = Path.of(System.getProperty("java.home"));
+        Path candidate = javaHome.resolve("bin").resolve(isWindows() ? "java.exe" : "java");
+        assertTrue(Files.isExecutable(candidate), "java binary must be executable: " + candidate);
+        return candidate.toString();
+    }
+
+    private static boolean isWindows() {
+        return System.getProperty("os.name", "").toLowerCase().contains("win");
+    }
+
+    private static Map<String, String> parseKeyValues(String output) {
+        Map<String, String> map = new HashMap<>();
+        for (String line : output.split("\\R")) {
+            int eq = line.indexOf('=');
+            if (eq > 0) {
+                map.put(line.substring(0, eq).trim(), line.substring(eq + 1).trim());
+            }
+        }
+        return map;
+    }
+}
diff --git a/src/test/java/com/github/copilot/InternalExecutorProviderProbe.java b/src/test/java/com/github/copilot/InternalExecutorProviderProbe.java
new file mode 100644
index 0000000000..85d12f14f1
--- /dev/null
+++ b/src/test/java/com/github/copilot/InternalExecutorProviderProbe.java
@@ -0,0 +1,74 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *--------------------------------------------------------------------------------------------*/
+
+package com.github.copilot;
+
+import java.lang.reflect.Method;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.Executor;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/**
+ * Diagnostic main launched as a separate JVM by
+ * {@code InternalExecutorProviderIT} to inspect the multi-release behaviour of
+ * {@link InternalExecutorProvider} against the actually packaged JAR.
+ * <p>
+ * Lives in the same package as {@link InternalExecutorProvider} so it can use
+ * its package-private API directly, without reflection.
+ * <p>
+ * Output format (key=value, one per line):
+ *
+ * <pre>
+ *   feature=&lt;JDK feature version&gt;
+ *   canBeShutdown=&lt;true|false&gt;
+ *   virtual=&lt;true|false&gt;
+ * </pre>
+ */
+final class InternalExecutorProviderProbe {
+
+    private InternalExecutorProviderProbe() {
+    }
+
+    public static void main(String[] args) throws Exception {
+        InternalExecutorProvider provider = new InternalExecutorProvider(null);
+        Executor executor = provider.get();
+        boolean canBeShutdown = provider.canBeShutdown();
+
+        AtomicBoolean virtual = new AtomicBoolean();
+        CountDownLatch latch = new CountDownLatch(1);
+        executor.execute(() -> {
+            try {
+                virtual.set(isCurrentThreadVirtual());
+            } finally {
+                latch.countDown();
+            }
+        });
+
+        try {
+            if (!latch.await(5, TimeUnit.SECONDS)) {
+                System.out.println("error=task-timeout");
+                System.exit(2);
+            }
+        } finally {
+            if (executor instanceof ExecutorService es) {
+                es.shutdownNow();
+            }
+        }
+
+        System.out.println("feature=" + Runtime.version().feature());
+        System.out.println("canBeShutdown=" + canBeShutdown);
+        System.out.println("virtual=" + virtual.get());
+    }
+
+    private static boolean isCurrentThreadVirtual() {
+        try {
+            Method isVirtual = Thread.class.getMethod("isVirtual");
+            return (Boolean) isVirtual.invoke(Thread.currentThread());
+        } catch (ReflectiveOperationException e) {
+            return false;
+        }
+    }
+}
diff --git a/src/test/java/com/github/copilot/InternalExecutorProviderTest.java b/src/test/java/com/github/copilot/InternalExecutorProviderTest.java
new file mode 100644
index 0000000000..f1d854cb53
--- /dev/null
+++ b/src/test/java/com/github/copilot/InternalExecutorProviderTest.java
@@ -0,0 +1,55 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *--------------------------------------------------------------------------------------------*/
+
+package com.github.copilot;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertSame;
+
+import java.lang.reflect.Modifier;
+import java.util.concurrent.Executor;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ForkJoinPool;
+
+import org.junit.jupiter.api.Test;
+
+import com.github.copilot.rpc.CopilotClientOptions;
+
+class InternalExecutorProviderTest {
+
+    @Test
+    void baseProviderReturnsCommonPool() {
+        Executor executor = new InternalExecutorProvider(null).get();
+
+        assertSame(ForkJoinPool.commonPool(), executor);
+    }
+
+    @Test
+    void userProvidedExecutorIsNotOwned() {
+        Executor executor = ForkJoinPool.commonPool();
+
+        assertFalse(new InternalExecutorProvider(executor).canBeShutdown());
+    }
+
+    @Test
+    void providerIsPackagePrivate() {
+        assertFalse(Modifier.isPublic(InternalExecutorProvider.class.getModifiers()));
+    }
+
+    @Test
+    void clientDoesNotShutDownUserProvidedExecutor() {
+        ExecutorService executor = Executors.newSingleThreadExecutor();
+        try {
+            try (var client = new CopilotClient(new CopilotClientOptions().setAutoStart(false).setExecutor(executor))) {
+                assertNotNull(client);
+            }
+
+            assertFalse(executor.isShutdown());
+        } finally {
+            executor.shutdownNow();
+        }
+    }
+}
diff --git a/src/test/java/com/github/copilot/SessionRequestBuilderTest.java b/src/test/java/com/github/copilot/SessionRequestBuilderTest.java
index 49a4c9c308..9fca584d1b 100644
--- a/src/test/java/com/github/copilot/SessionRequestBuilderTest.java
+++ b/src/test/java/com/github/copilot/SessionRequestBuilderTest.java
@@ -21,6 +21,7 @@
 import com.github.copilot.rpc.ElicitationResult;
 import com.github.copilot.rpc.ElicitationResultAction;
 import com.github.copilot.rpc.ExitPlanModeResult;
+import com.github.copilot.rpc.LargeToolOutputConfig;
 import com.github.copilot.rpc.ResumeSessionConfig;
 import com.github.copilot.rpc.ResumeSessionRequest;
 import com.github.copilot.rpc.SessionConfig;
@@ -90,6 +91,23 @@ void testBuildCreateRequestSetsClientName() {
         assertEquals("my-app", request.getClientName());
     }
 
+    @Test
+    void testBuildCreateRequestSetsReasoningSummary() {
+        var config = new SessionConfig().setReasoningSummary("concise");
+        CreateSessionRequest request = SessionRequestBuilder.buildCreateRequest(config);
+        assertEquals("concise", request.getReasoningSummary());
+    }
+
+    @Test
+    void testBuildCreateRequestSetsPluginDirectoriesAndLargeOutput() {
+        var largeOutput = new LargeToolOutputConfig().setEnabled(true).setMaxSizeBytes(1024L)
+                .setOutputDirectory("/tmp/out");
+        var config = new SessionConfig().setPluginDirectories(List.of("/plugins/a")).setLargeOutput(largeOutput);
+        CreateSessionRequest request = SessionRequestBuilder.buildCreateRequest(config);
+        assertEquals(List.of("/plugins/a"), request.getPluginDirectories());
+        assertEquals(largeOutput, request.getLargeOutput());
+    }
+
     @Test
     void testBuildCreateRequestForwardsEnableSessionTelemetryWhenFalse() {
         var config = new SessionConfig().setEnableSessionTelemetry(false);
@@ -104,6 +122,26 @@ void testBuildCreateRequestOmitsEnableSessionTelemetryWhenNotSet() {
         assertNull(request.getEnableSessionTelemetry());
     }
 
+    @Test
+    void testBuildCreateRequestPassesThroughNullMcpOAuthTokenStorage() {
+        var config = new SessionConfig();
+        CreateSessionRequest request = SessionRequestBuilder.buildCreateRequest(config);
+        assertNull(request.getMcpOAuthTokenStorage());
+    }
+
+    @Test
+    void testBuildCreateRequestForwardsExplicitMcpOAuthTokenStorage() {
+        var config = new SessionConfig().setMcpOAuthTokenStorage("persistent");
+        CreateSessionRequest request = SessionRequestBuilder.buildCreateRequest(config);
+        assertEquals("persistent", request.getMcpOAuthTokenStorage());
+    }
+
+    @Test
+    void testBuildCreateRequestNullConfigHasNullMcpOAuthTokenStorage() {
+        CreateSessionRequest request = SessionRequestBuilder.buildCreateRequest(null);
+        assertNull(request.getMcpOAuthTokenStorage());
+    }
+
     // =========================================================================
     // buildResumeRequest
     // =========================================================================
@@ -212,6 +250,43 @@ void testBuildResumeRequestSetsClientName() {
         assertEquals("my-app", request.getClientName());
     }
 
+    @Test
+    void testBuildResumeRequestPassesThroughNullMcpOAuthTokenStorage() {
+        var config = new ResumeSessionConfig();
+        ResumeSessionRequest request = SessionRequestBuilder.buildResumeRequest("sid-11", config);
+        assertNull(request.getMcpOAuthTokenStorage());
+    }
+
+    @Test
+    void testBuildResumeRequestForwardsExplicitMcpOAuthTokenStorage() {
+        var config = new ResumeSessionConfig().setMcpOAuthTokenStorage("persistent");
+        ResumeSessionRequest request = SessionRequestBuilder.buildResumeRequest("sid-12", config);
+        assertEquals("persistent", request.getMcpOAuthTokenStorage());
+    }
+
+    @Test
+    void testBuildResumeRequestNullConfigHasNullMcpOAuthTokenStorage() {
+        ResumeSessionRequest request = SessionRequestBuilder.buildResumeRequest("sid-13", null);
+        assertNull(request.getMcpOAuthTokenStorage());
+    }
+
+    @Test
+    void testBuildResumeRequestSetsReasoningSummary() {
+        var config = new ResumeSessionConfig().setReasoningSummary("none");
+        ResumeSessionRequest request = SessionRequestBuilder.buildResumeRequest("sid-14", config);
+        assertEquals("none", request.getReasoningSummary());
+    }
+
+    @Test
+    void testBuildResumeRequestSetsPluginDirectoriesAndLargeOutput() {
+        var largeOutput = new LargeToolOutputConfig().setEnabled(false).setMaxSizeBytes(2048L)
+                .setOutputDirectory("/tmp/resume");
+        var config = new ResumeSessionConfig().setPluginDirectories(List.of("/plugins/r")).setLargeOutput(largeOutput);
+        ResumeSessionRequest request = SessionRequestBuilder.buildResumeRequest("sid-15", config);
+        assertEquals(List.of("/plugins/r"), request.getPluginDirectories());
+        assertEquals(largeOutput, request.getLargeOutput());
+    }
+
     // =========================================================================
     // configureSession (ResumeSessionConfig overload)
     // =========================================================================

From da3f8c7e77a0307e366207fc033dd2298ec7915b Mon Sep 17 00:00:00 2001
From: Ed Burns <edburns@microsoft.com>
Date: Thu, 28 May 2026 15:57:44 -0700
Subject: [PATCH 2/3] Apply
 https://github.com/github/copilot-sdk-java/pull/237#discussion_r3321064387

---
 .../java/com/github/copilot/rpc/LargeToolOutputConfig.java  | 5 +++++
 .../java/com/github/copilot/rpc/ResumeSessionConfig.java    | 6 ++++--
 src/main/java/com/github/copilot/rpc/SessionConfig.java     | 6 ++++--
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/main/java/com/github/copilot/rpc/LargeToolOutputConfig.java b/src/main/java/com/github/copilot/rpc/LargeToolOutputConfig.java
index 1694761e2b..cd1e6b5252 100644
--- a/src/main/java/com/github/copilot/rpc/LargeToolOutputConfig.java
+++ b/src/main/java/com/github/copilot/rpc/LargeToolOutputConfig.java
@@ -1,3 +1,8 @@
+/*
+ * Copyright (c) Microsoft Corporation. All rights reserved.
+ * Licensed under the MIT License.
+ */
+
 package com.github.copilot.rpc;
 
 import com.fasterxml.jackson.annotation.JsonInclude;
diff --git a/src/main/java/com/github/copilot/rpc/ResumeSessionConfig.java b/src/main/java/com/github/copilot/rpc/ResumeSessionConfig.java
index 3cdf191826..d254d73eb4 100644
--- a/src/main/java/com/github/copilot/rpc/ResumeSessionConfig.java
+++ b/src/main/java/com/github/copilot/rpc/ResumeSessionConfig.java
@@ -787,8 +787,10 @@ public String getMcpOAuthTokenStorage() {
      * <li>{@code "in-memory"} — tokens are stored in memory and discarded when the
      * session ends</li>
      * </ul>
-     * If not set, the SDK defaults to {@code "in-memory"} for safe multitenant
-     * behavior.
+     * If not set and the client is in
+     * {@link com.github.copilot.CopilotClientMode#EMPTY EMPTY} mode, the SDK
+     * defaults to {@code "in-memory"} for safe multitenant behavior. In other modes
+     * this field is left unset.
      *
      * @param mcpOAuthTokenStorage
      *            the storage mode
diff --git a/src/main/java/com/github/copilot/rpc/SessionConfig.java b/src/main/java/com/github/copilot/rpc/SessionConfig.java
index c845306879..ead3801b87 100644
--- a/src/main/java/com/github/copilot/rpc/SessionConfig.java
+++ b/src/main/java/com/github/copilot/rpc/SessionConfig.java
@@ -697,8 +697,10 @@ public String getMcpOAuthTokenStorage() {
      * <li>{@code "in-memory"} — tokens are stored in memory and discarded when the
      * session ends</li>
      * </ul>
-     * If not set, the SDK defaults to {@code "in-memory"} for safe multitenant
-     * behavior.
+     * If not set and the client is in
+     * {@link com.github.copilot.CopilotClientMode#EMPTY EMPTY} mode, the SDK
+     * defaults to {@code "in-memory"} for safe multitenant behavior. In other modes
+     * this field is left unset.
      *
      * @param mcpOAuthTokenStorage
      *            the storage mode

From 1f46ecf2cfe1196310866ae58a19455c8b05a6fa Mon Sep 17 00:00:00 2001
From: Ed Burns <edburns@microsoft.com>
Date: Thu, 28 May 2026 16:02:04 -0700
Subject: [PATCH 3/3] Apply
 https://github.com/github/copilot-sdk-java/pull/237#discussion_r3321064405

---
 .github/workflows/build-test.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/build-test.yml b/.github/workflows/build-test.yml
index dbc7406993..455e5a8201 100644
--- a/.github/workflows/build-test.yml
+++ b/.github/workflows/build-test.yml
@@ -176,4 +176,5 @@ jobs:
           path: |
             target/surefire-reports/
             target/surefire-reports-isolated/
+            target/failsafe-reports/
           retention-days: 7