diff --git a/bridge/symfony-console/src/Command/Run.php b/bridge/symfony-console/src/Command/Run.php
index 586bb475..2464406b 100644
--- a/bridge/symfony-console/src/Command/Run.php
+++ b/bridge/symfony-console/src/Command/Run.php
@@ -9,6 +9,7 @@
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Input\InputOption;
 use Symfony\Component\Console\Output\OutputInterface;
+use Testo\Output\Html\HtmlPlugin;
 use Testo\Output\Json\JsonPlugin;
 use Testo\Output\Teamcity\TeamcityPlugin;
 use Testo\Output\Terminal\TerminalPlugin;
@@ -154,9 +155,10 @@ public function configure(): void
         $this->addOption(
             'log-html',
             null,
-            InputOption::VALUE_REQUIRED,
+            InputOption::VALUE_OPTIONAL,
             'Write a self-contained HTML report. A path ending in ".html" produces that single file; '
             . 'anything else is a directory to fill with index.html and its assets. '
+            . 'Without a value the report goes to ' . HtmlPlugin::DEFAULT_PATH . '. '
             . 'The report opens over file:// with no server.',
         );
         // $this->addOption(
@@ -219,4 +221,21 @@ public function __invoke(
             ? Command::SUCCESS
             : Command::FAILURE;
     }
+
+    /**
+     * Exists because the option definition cannot express "a bare `--log-html` falls back to the default
+     * path": a VALUE_OPTIONAL option reports null both when absent and when passed without a value, and a
+     * declared default would fire for the absent case too — so the two nulls are told apart against the
+     * raw parameters instead. Lives in `initialize()` and not in `__invoke()` with the other flags
+     * because {@see Base::execute()} snapshots the options for config hydration between the two — any
+     * later, and the resolved path would never reach the reporter.
+     */
+    #[\Override]
+    protected function initialize(InputInterface $input, OutputInterface $output): void
+    {
+        parent::initialize($input, $output);
+
+        $input->getOption('log-html') === null && $input->hasParameterOption('--log-html', true)
+            and $input->setOption('log-html', HtmlPlugin::DEFAULT_PATH);
+    }
 }
diff --git a/bridge/symfony-console/tests/Acceptance/RunCommandTest.php b/bridge/symfony-console/tests/Acceptance/RunCommandTest.php
new file mode 100644
index 00000000..1f6ca08b
--- /dev/null
+++ b/bridge/symfony-console/tests/Acceptance/RunCommandTest.php
@@ -0,0 +1,161 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Bridge\SymfonyConsole\Acceptance;
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Tester\CommandTester;
+use Testo\Assert;
+use Testo\Bridge\Symfony\Console\Command\Run;
+use Testo\Codecov\Covers;
+use Testo\Lifecycle\AfterTest;
+use Testo\Lifecycle\BeforeTest;
+use Testo\Output\Html\HtmlPlugin;
+use Testo\Test;
+use Tests\Bridge\SymfonyConsole\Testo\Sandbox;
+
+/**
+ * Acceptance tests for the `--log-html` flag of `testo run`.
+ *
+ * Each test drives the real command end-to-end — Symfony parses the flags, {@see Run::initialize()}
+ * normalizes them and a whole nested run happens in-process — inside a fresh {@see Sandbox} holding a
+ * minimal config that points at a one-test stub suite. Assertions look at the exit code, the resolved
+ * option and the files the run leaves on disk: the same surface a user observes after
+ * `vendor/bin/testo --log-html`.
+ *
+ * The sandbox config swaps the default reporter for a fresh {@see HtmlPlugin::inert()} of its own: the
+ * application defaults hold one shared instance per process, and its single-shot guard is already spent
+ * by the outer run that executes these tests — without the swap a nested run could write no report no
+ * matter what the flag says.
+ */
+#[Test]
+#[Covers(Run::class)]
+final class RunCommandTest
+{
+    private Sandbox $sandbox;
+
+    public function bareLogHtmlWritesTheReportToTheDefaultLocation(): void
+    {
+        $tester = $this->run(['--log-html' => null]);
+
+        Assert::same(
+            $tester->getStatusCode(),
+            Command::SUCCESS,
+            'a valueless --log-html must be accepted, not rejected by the parser; output: ' . $tester->getDisplay(),
+        );
+        Assert::same(
+            $tester->getInput()->getOption('log-html'),
+            HtmlPlugin::DEFAULT_PATH,
+            'a bare --log-html must fall back to the default report location',
+        );
+        Assert::true(
+            \is_file($this->sandbox->path('runtime/report/index.html')),
+            'a bare --log-html must write the report to runtime/report/index.html; output: ' . $tester->getDisplay(),
+        );
+    }
+
+    public function logHtmlWithAnExplicitPathWritesThatSingleFile(): void
+    {
+        $tester = $this->run(['--log-html' => 'build/report.html']);
+
+        Assert::same(
+            $tester->getStatusCode(),
+            Command::SUCCESS,
+            'the stub suite must pass; output: ' . $tester->getDisplay(),
+        );
+        Assert::true(
+            \is_file($this->sandbox->path('build/report.html')),
+            'an explicit .html path must produce that single file, untouched by the bare-flag fallback; output: '
+            . $tester->getDisplay(),
+        );
+        Assert::false(
+            \is_dir($this->sandbox->path('runtime/report')),
+            'the default location must stay untouched when a path is given',
+        );
+    }
+
+    public function withoutTheFlagNothingIsResolvedAndNoReportIsWritten(): void
+    {
+        $tester = $this->run();
+
+        Assert::same(
+            $tester->getStatusCode(),
+            Command::SUCCESS,
+            'the stub suite must pass; output: ' . $tester->getDisplay(),
+        );
+        Assert::null(
+            $tester->getInput()->getOption('log-html'),
+            'an absent flag must stay absent — the fallback belongs to the bare flag only',
+        );
+        Assert::false(
+            \is_dir($this->sandbox->path('runtime')),
+            'a run without the flag must leave no report behind',
+        );
+    }
+
+    #[BeforeTest]
+    public function setUp(): void
+    {
+        $this->sandbox = Sandbox::create();
+        $this->sandbox->writeFile('testo.php', self::configPointingAtTheStubSuite());
+    }
+
+    #[AfterTest]
+    public function tearDown(): void
+    {
+        $this->sandbox->destroy();
+    }
+
+    /**
+     * The smallest config a nested run needs: no sources, one suite pointing at this module's stub case,
+     * and a fresh inert reporter in place of the process-wide default (see the class docblock).
+     * The stub directory is embedded as an absolute path — the sandbox CWD is elsewhere.
+     */
+    private static function configPointingAtTheStubSuite(): string
+    {
+        $stub = \var_export(\dirname(__DIR__) . '/Stub/Run', true);
+
+        return <<<PHP
+            <?php
+
+            declare(strict_types=1);
+
+            use Testo\\Application\\Config\\ApplicationConfig;
+            use Testo\\Application\\Config\\FinderConfig;
+            use Testo\\Application\\Config\\Plugin\\ApplicationPlugins;
+            use Testo\\Application\\Config\\SuiteConfig;
+            use Testo\\Output\\Html\\HtmlPlugin;
+
+            return new ApplicationConfig(
+                src: [],
+                suites: [
+                    new SuiteConfig(
+                        'Stub',
+                        location: new FinderConfig(include: [{$stub}]),
+                    ),
+                ],
+                plugins: ApplicationPlugins::without(HtmlPlugin::class)->with(HtmlPlugin::inert()),
+            );
+            PHP;
+    }
+
+    /**
+     * Run the `run` command against the sandbox config in non-interactive mode.
+     *
+     * Pass CLI flags as the standard CommandTester input array; a bare flag is a key with a null value,
+     * e.g. `['--log-html' => null]`.
+     *
+     * @param array<string, string|bool|null> $input
+     */
+    private function run(array $input = []): CommandTester
+    {
+        $tester = new CommandTester(new Run());
+        $tester->execute(
+            $input,
+            ['interactive' => false, 'capture_stderr_separately' => false],
+        );
+
+        return $tester;
+    }
+}
diff --git a/bridge/symfony-console/tests/Stub/Run/PassingCase.php b/bridge/symfony-console/tests/Stub/Run/PassingCase.php
new file mode 100644
index 00000000..afafb38b
--- /dev/null
+++ b/bridge/symfony-console/tests/Stub/Run/PassingCase.php
@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Bridge\SymfonyConsole\Stub\Run;
+
+use Testo\Assert;
+use Testo\Test;
+
+/**
+ * A minimal case for the `run` command acceptance tests to execute: one test that passes and asserts
+ * something, so a nested run has a suite, a case, a test and a green status to report.
+ */
+#[Test]
+final class PassingCase
+{
+    public function itPasses(): void
+    {
+        Assert::true(true);
+    }
+}
diff --git a/core/Output/Html/HtmlPlugin.php b/core/Output/Html/HtmlPlugin.php
index cd6361cf..a9763701 100644
--- a/core/Output/Html/HtmlPlugin.php
+++ b/core/Output/Html/HtmlPlugin.php
@@ -40,7 +40,8 @@
  * ```
  *
  * An inert copy — {@see inert()} — is part of the application defaults, so the `--log-html=<path>` and
- * `--log-report=<path>` flags have something to activate without any change to `testo.php`. An instance
+ * `--log-report=<path>` flags have something to activate without any change to `testo.php`; a bare
+ * `--log-html` activates it at {@see self::DEFAULT_PATH}. An instance
  * configured in code owns its slots and ignores the flags; only an instance with no destination of its
  * own reads them, which is how the inert default gets activated. Every destination a run collects — from
  * configured plugins and from flags — feeds a single {@see HtmlReportSink}: the document is built once
diff --git a/skills/testo-run-tests/SKILL.md b/skills/testo-run-tests/SKILL.md
index ab25570f..e7509e9c 100644
--- a/skills/testo-run-tests/SKILL.md
+++ b/skills/testo-run-tests/SKILL.md
@@ -103,7 +103,8 @@ over-narrow filter — widen it (a typo in `--filter`, a `--path` that matches n
 
 - Coverage (`--coverage`, `--coverage-clover=`, `--coverage-level=`, …) — see the
   `testo-coverage` skill.
-- `--log-junit=`, `--log-html=` (a `.html` path → single file, anything else → directory),
+- `--log-junit=`, `--log-html=` (a `.html` path → single file, anything else → directory;
+  bare `--log-html` → `runtime/report`),
   `--log-report=` (the full run as a versioned JSON document — the data behind the HTML),
   `--teamcity` — reports for CI and IDEs, not for agent parsing.
 - `--config=path/to/testo.php` when the config is not at the project root.