diff --git a/phpcs.xml.dist b/phpcs.xml.dist
index 3ca00dd..cb86435 100644
--- a/phpcs.xml.dist
+++ b/phpcs.xml.dist
@@ -2,6 +2,7 @@
 <ruleset name="wp-lit-mcp">
     <file>src</file>
     <file>wp-lit-mcp.php</file>
+    <file>uninstall.php</file>
     <exclude-pattern>/vendor/*</exclude-pattern>
     <arg value="sp"/>
     <arg name="extensions" value="php"/>
diff --git a/src/Lifecycle.php b/src/Lifecycle.php
index b19b281..7b296c5 100644
--- a/src/Lifecycle.php
+++ b/src/Lifecycle.php
@@ -4,12 +4,15 @@ declare(strict_types=1);
 
 namespace LIT\MCP;
 
+use LIT\MCP\Admin\ConnectionStatus;
 use LIT\MCP\ChangeLog\ChangeLog;
 use LIT\MCP\ChangeLog\ChangeLogCleanup;
 use LIT\MCP\ChangeLog\ChangeLogInstaller;
+use WPMedia\MCP\OAuth\Bootstrap as OAuthBootstrap;
 
 /**
- * Activation and deactivation hooks (registered in wp-lit-mcp.php).
+ * Activation and deactivation hooks (registered in wp-lit-mcp.php). Uninstall
+ * lives in uninstall.php.
  */
 final class Lifecycle
 {
@@ -18,10 +21,20 @@ final class Lifecycle
         $log = new ChangeLog();
         (new ChangeLogInstaller($log))->install();
         (new ChangeLogCleanup($log, new Limits()))->ensureScheduled();
+
+        if (class_exists(OAuthBootstrap::class)) {
+            // mcp-oauth's public API: rewrite its /oauth and /.well-known rules on the next init.
+            OAuthBootstrap::schedule_rewrite_flush();
+        }
     }
 
     public static function deactivate(): void
     {
         wp_clear_scheduled_hook(ChangeLogCleanup::HOOK);
+        delete_transient(ConnectionStatus::ENDPOINT_TRANSIENT);
+        // WordPress regenerates the rules on the next request – without those of this now
+        // inactive plugin. Calling flush_rewrite_rules() here instead would rewrite them
+        // including our rules, because the plugin is still loaded during this request.
+        delete_option('rewrite_rules');
     }
 }
diff --git a/src/Uninstaller.php b/src/Uninstaller.php
new file mode 100644
index 0000000..60b98d9
--- /dev/null
+++ b/src/Uninstaller.php
@@ -0,0 +1,62 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP;
+
+/**
+ * Removes WP-LIT-MCP's own data (uninstall.php, Task 12): options, the endpoint-check
+ * transient, the log-cleanup cron hook and the change log table – on every site of a
+ * network.
+ *
+ * Deliberately self-contained (no reference to any other LIT\MCP\* class): uninstall.php
+ * is executed by WordPress core standalone, without loading the plugin's main file first,
+ * so the Composer/Jetpack autoloader is not guaranteed to have run. The option/hook/table
+ * names below are therefore duplicated from Access::OPTION, Abilities\ExposurePolicy::OPTION,
+ * Limits::OPTION, ChangeLog\ChangeLogInstaller::VERSION_OPTION, Admin\ConnectionStatus::
+ * ENDPOINT_TRANSIENT, ChangeLog\ChangeLogCleanup::HOOK and ChangeLog\ChangeLog::TABLE on
+ * purpose; tests/Unit/UninstallerTest.php and tests/Unit/UninstallTest.php keep them in
+ * sync with those constants.
+ *
+ * Never touches the bundled wp-media/mcp-oauth library's data (option mcp_jwt_secret,
+ * option wpmedia_mcp_oauth_rewrite_version, user meta mcp_refresh_jti_*, application
+ * passwords of connected clients) – that library may be shared with other plugins on
+ * this site. Never deletes posts, attachments or revisions.
+ */
+final class Uninstaller
+{
+    private const OPTIONS = ['lit_mcp_allowed_roles', 'lit_mcp_exposure', 'lit_mcp_limits', 'lit_mcp_db_version'];
+    private const TRANSIENT = 'lit_mcp_endpoint_check';
+    private const CRON_HOOK = 'lit_mcp_log_cleanup';
+    private const TABLE = 'lit_mcp_log';
+
+    public static function run(): void
+    {
+        if (! is_multisite()) {
+            self::removeSiteData();
+
+            return;
+        }
+
+        foreach (get_sites(['fields' => 'ids', 'number' => 0]) as $site_id) {
+            switch_to_blog((int) $site_id);
+            self::removeSiteData();
+            restore_current_blog();
+        }
+    }
+
+    public static function removeSiteData(): void
+    {
+        global $wpdb;
+
+        foreach (self::OPTIONS as $option) {
+            delete_option($option);
+        }
+        delete_transient(self::TRANSIENT);
+        wp_clear_scheduled_hook(self::CRON_HOOK);
+
+        $table = $wpdb->prefix . self::TABLE;
+        // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- own table name, not user input.
+        $wpdb->query("DROP TABLE IF EXISTS {$table}");
+    }
+}
diff --git a/tests/Unit/LifecycleTest.php b/tests/Unit/LifecycleTest.php
index 2082d4c..850c57f 100644
--- a/tests/Unit/LifecycleTest.php
+++ b/tests/Unit/LifecycleTest.php
@@ -16,20 +16,23 @@ final class LifecycleTest extends TestCase
         parent::tearDown();
     }
 
-    public function testActivateInstallsTheTableAndSchedulesTheCleanup(): void
+    public function testActivateInstallsTableSchedulesCleanupAndRequestsOauthRewriteFlush(): void
     {
         $GLOBALS['wpdb'] = Mockery::mock(\wpdb::class)->makePartial();
         Functions\expect('dbDelta')->once();
         Functions\expect('update_option')->once()->with('lit_mcp_db_version', '1');
         Functions\when('wp_next_scheduled')->justReturn(false);
         Functions\expect('wp_schedule_event')->once();
+        Functions\expect('delete_option')->once()->with('wpmedia_mcp_oauth_rewrite_version');
 
         Lifecycle::activate();
     }
 
-    public function testDeactivateUnschedulesTheCleanup(): void
+    public function testDeactivateRemovesCronTransientAndStoredRewriteRules(): void
     {
         Functions\expect('wp_clear_scheduled_hook')->once()->with('lit_mcp_log_cleanup');
+        Functions\expect('delete_transient')->once()->with('lit_mcp_endpoint_check');
+        Functions\expect('delete_option')->once()->with('rewrite_rules');
 
         Lifecycle::deactivate();
     }
diff --git a/tests/Unit/UninstallTest.php b/tests/Unit/UninstallTest.php
new file mode 100644
index 0000000..03cd509
--- /dev/null
+++ b/tests/Unit/UninstallTest.php
@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Tests\Unit;
+
+use Brain\Monkey\Functions;
+use LIT\MCP\Abilities\ExposurePolicy;
+use LIT\MCP\Access;
+use LIT\MCP\Admin\ConnectionStatus;
+use LIT\MCP\ChangeLog\ChangeLogCleanup;
+use LIT\MCP\ChangeLog\ChangeLogInstaller;
+use LIT\MCP\Limits;
+use Mockery;
+
+final class UninstallTest extends TestCase
+{
+    protected function tearDown(): void
+    {
+        unset($GLOBALS['wpdb']);
+        parent::tearDown();
+    }
+
+    public function testRemovesOnlyOwnDataOnEverySite(): void
+    {
+        if (! defined('WP_UNINSTALL_PLUGIN')) {
+            define('WP_UNINSTALL_PLUGIN', 'WP-LIT-MCP/wp-lit-mcp.php');
+        }
+        $db = Mockery::mock(\wpdb::class)->makePartial();
+        $db->expects('query')->twice()->with('DROP TABLE IF EXISTS wp_lit_mcp_log');
+        $GLOBALS['wpdb'] = $db;
+        Functions\when('is_multisite')->justReturn(true);
+        Functions\when('get_sites')->justReturn([1, 2]);
+        Functions\expect('switch_to_blog')->twice();
+        Functions\expect('restore_current_blog')->twice();
+        Functions\expect('delete_transient')->twice()->with(ConnectionStatus::ENDPOINT_TRANSIENT);
+        Functions\expect('wp_clear_scheduled_hook')->twice()->with(ChangeLogCleanup::HOOK);
+        $deleted = [];
+        Functions\when('delete_option')->alias(static function (string $option) use (&$deleted): bool {
+            $deleted[] = $option;
+            return true;
+        });
+
+        require dirname(__DIR__, 2) . '/uninstall.php';
+
+        $own = [Access::OPTION, ExposurePolicy::OPTION, Limits::OPTION, ChangeLogInstaller::VERSION_OPTION];
+        self::assertSame(array_merge($own, $own), $deleted);
+        self::assertNotContains('mcp_jwt_secret', $deleted);
+        self::assertNotContains('wpmedia_mcp_oauth_rewrite_version', $deleted);
+    }
+}
diff --git a/tests/Unit/UninstallerTest.php b/tests/Unit/UninstallerTest.php
new file mode 100644
index 0000000..e23435b
--- /dev/null
+++ b/tests/Unit/UninstallerTest.php
@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Tests\Unit;
+
+use Brain\Monkey\Functions;
+use LIT\MCP\Abilities\ExposurePolicy;
+use LIT\MCP\Access;
+use LIT\MCP\Admin\ConnectionStatus;
+use LIT\MCP\ChangeLog\ChangeLogCleanup;
+use LIT\MCP\ChangeLog\ChangeLogInstaller;
+use LIT\MCP\Limits;
+use LIT\MCP\Uninstaller;
+use Mockery;
+
+/**
+ * Unit tests for the cleanup logic itself (extracted from uninstall.php so it is
+ * testable without requiring that top-level script). tests/Unit/UninstallTest.php
+ * additionally exercises uninstall.php's wiring to this class.
+ */
+final class UninstallerTest extends TestCase
+{
+    protected function tearDown(): void
+    {
+        unset($GLOBALS['wpdb']);
+        parent::tearDown();
+    }
+
+    public function testRunRemovesOwnDataOnceOnASingleSite(): void
+    {
+        $db = Mockery::mock(\wpdb::class)->makePartial();
+        $db->expects('query')->once()->with('DROP TABLE IF EXISTS wp_lit_mcp_log');
+        $GLOBALS['wpdb'] = $db;
+        Functions\when('is_multisite')->justReturn(false);
+        Functions\expect('switch_to_blog')->never();
+        Functions\expect('restore_current_blog')->never();
+        Functions\expect('delete_transient')->once()->with(ConnectionStatus::ENDPOINT_TRANSIENT);
+        Functions\expect('wp_clear_scheduled_hook')->once()->with(ChangeLogCleanup::HOOK);
+        $deleted = [];
+        Functions\when('delete_option')->alias(static function (string $option) use (&$deleted): bool {
+            $deleted[] = $option;
+            return true;
+        });
+
+        Uninstaller::run();
+
+        self::assertSame(
+            [Access::OPTION, ExposurePolicy::OPTION, Limits::OPTION, ChangeLogInstaller::VERSION_OPTION],
+            $deleted
+        );
+    }
+
+    public function testRunRemovesDataOnEverySiteOfAMultisiteNetwork(): void
+    {
+        $db = Mockery::mock(\wpdb::class)->makePartial();
+        $db->expects('query')->twice()->with('DROP TABLE IF EXISTS wp_lit_mcp_log');
+        $GLOBALS['wpdb'] = $db;
+        Functions\when('is_multisite')->justReturn(true);
+        Functions\when('get_sites')->justReturn([1, 2]);
+        Functions\expect('switch_to_blog')->twice();
+        Functions\expect('restore_current_blog')->twice();
+        Functions\expect('delete_transient')->twice()->with(ConnectionStatus::ENDPOINT_TRANSIENT);
+        Functions\expect('wp_clear_scheduled_hook')->twice()->with(ChangeLogCleanup::HOOK);
+        Functions\when('delete_option')->justReturn(true);
+
+        Uninstaller::run();
+    }
+}
diff --git a/uninstall.php b/uninstall.php
new file mode 100644
index 0000000..cb6fd9e
--- /dev/null
+++ b/uninstall.php
@@ -0,0 +1,27 @@
+<?php
+
+/**
+ * Uninstall WP-LIT-MCP: removes its own data only, on every site of a network.
+ *
+ * Removed: options lit_mcp_allowed_roles, lit_mcp_exposure, lit_mcp_limits, lit_mcp_db_version,
+ * transient lit_mcp_endpoint_check, cron hook lit_mcp_log_cleanup, table {prefix}lit_mcp_log.
+ *
+ * Kept on purpose: data of the bundled wp-media/mcp-oauth library (option mcp_jwt_secret,
+ * option wpmedia_mcp_oauth_rewrite_version, user meta mcp_refresh_jti_*, application passwords
+ * of connected clients). The library may be used by other plugins on this site; see readme.txt.
+ * Posts, attachments and revisions are never touched.
+ *
+ * The cleanup logic lives in src/Uninstaller.php, required directly below by path rather
+ * than through the Composer/Jetpack autoloader: WordPress core runs uninstall.php standalone
+ * without loading the plugin's main file, so that autoloader is not guaranteed to have run.
+ * tests/Unit/UninstallerTest.php unit-tests that class; tests/Unit/UninstallTest.php exercises
+ * this script's wiring to it.
+ */
+
+declare(strict_types=1);
+
+defined('WP_UNINSTALL_PLUGIN') || exit;
+
+require_once __DIR__ . '/src/Uninstaller.php';
+
+\LIT\MCP\Uninstaller::run();