disable the screenshots tool by default (#210)
Disabling due to https://github.com/flutter/flutter/issues/170357 - this only works today by default on the desktop environment.
We could fall back on full device screenshots but are holding off on that for now as we have to evaluate some extra potential privacy concerns with exposing the entire screen as opposed to just the flutter drawn pixels.
diff --git a/pkgs/dart_mcp_server/CHANGELOG.md b/pkgs/dart_mcp_server/CHANGELOG.md
index c641328..635f677 100644
--- a/pkgs/dart_mcp_server/CHANGELOG.md
+++ b/pkgs/dart_mcp_server/CHANGELOG.md
@@ -42,4 +42,6 @@
* Add `--log-file` argument to log all protocol traffic to a file.
* Improve error text for failed DTD connections as well as the tool description.
* Add support for injecting an `Analytics` instance to track usage.
+* Screenshot tool disabled until
+ https://github.com/flutter/flutter/issues/170357 is resolved.
* Add `arg_parser.dart` public library with minimal deps to be used by the dart tool.
diff --git a/pkgs/dart_mcp_server/README.md b/pkgs/dart_mcp_server/README.md
index f663788..a56aedd 100644
--- a/pkgs/dart_mcp_server/README.md
+++ b/pkgs/dart_mcp_server/README.md
@@ -74,7 +74,7 @@
[](https://cursor.com/install-mcp?name=dart&config=eyJ0eXBlIjoic3RkaW8iLCJjb21tYW5kIjoiZGFydCBtY3Atc2VydmVyIC0tZXhwZXJpbWVudGFsLW1jcC1zZXJ2ZXIgLS1mb3JjZS1yb290cy1mYWxsYmFjayJ9)
The easiest way to configure the Dart MCP server with Cursor is by clicking the "Add to Cursor"
-button above.
+button above.
Alternatively, you can configure the server manually. Go to **Cursor -> Settings -> Cursor Settings > Tools & Integrations**, and then click **"Add Custom MCP"** or **"New MCP Server"**
depending on whether you already have other MCP servers configured. Edit the `.cursor/mcp.json` file in your local project (configuration will only apply to this project) or
@@ -155,7 +155,6 @@
| `pub` | `static tool` | Runs a `dart pub` command for the given project roots. |
| `pub_dev_search` | `package search` | Searches pub.dev for packages relevant to a given search query. |
| `get_runtime_errors` | `runtime analysis` | Retrieves the list of runtime errors that have occurred in the active Dart or Flutter application. |
-| `take_screenshot` | `runtime analysis` | Takes a screenshot of the active Flutter application in its current state. |
| `get_widget_tree` | `runtime analysis` | Retrieves the widget tree from the active Flutter application. |
| `get_selected_widget` | `runtime analysis` | Retrieves the selected widget from the active Flutter application. |
| `hot_reload` | `runtime tool` | Performs a hot reload of the active Flutter application. |
diff --git a/pkgs/dart_mcp_server/lib/src/mixins/dtd.dart b/pkgs/dart_mcp_server/lib/src/mixins/dtd.dart
index 8fe2f8e..580ce6b 100644
--- a/pkgs/dart_mcp_server/lib/src/mixins/dtd.dart
+++ b/pkgs/dart_mcp_server/lib/src/mixins/dtd.dart
@@ -61,6 +61,9 @@
/// for full list of available Flutter Widget Inspector service extensions.
static const _inspectorServiceExtensionPrefix = 'ext.flutter.inspector';
+ /// Whether or not to enable the screenshot tool.
+ bool get enableScreenshots;
+
/// Called when the DTD connection is lost, resets all associated state.
Future<void> _resetDtd() async {
_dtd = null;
@@ -165,7 +168,7 @@
// they should return an error when used against a pure Dart app (or a
// Flutter app that does not support the operation, e.g. hot reload is not
// supported in profile mode).
- registerTool(screenshotTool, takeScreenshot);
+ if (enableScreenshots) registerTool(screenshotTool, takeScreenshot);
registerTool(hotReloadTool, hotReload);
registerTool(getWidgetTreeTool, widgetTree);
registerTool(getSelectedWidgetTool, selectedWidget);
diff --git a/pkgs/dart_mcp_server/lib/src/server.dart b/pkgs/dart_mcp_server/lib/src/server.dart
index d685e5a..005a68b 100644
--- a/pkgs/dart_mcp_server/lib/src/server.dart
+++ b/pkgs/dart_mcp_server/lib/src/server.dart
@@ -52,6 +52,8 @@
@visibleForTesting this.processManager = const LocalProcessManager(),
@visibleForTesting this.fileSystem = const LocalFileSystem(),
this.forceRootsFallback = false,
+ // Disabled due to https://github.com/flutter/flutter/issues/170357
+ this.enableScreenshots = false,
super.protocolLogSink,
}) : super.fromStreamChannel(
implementation: Implementation(
@@ -157,6 +159,9 @@
final Analytics? analytics;
@override
+ final bool enableScreenshots;
+
+ @override
/// Automatically logs all tool calls via analytics by wrapping the [impl],
/// if [analytics] is not `null`.
void registerTool(
diff --git a/pkgs/dart_mcp_server/test/test_harness.dart b/pkgs/dart_mcp_server/test/test_harness.dart
index 1f36e54..178304b 100644
--- a/pkgs/dart_mcp_server/test/test_harness.dart
+++ b/pkgs/dart_mcp_server/test/test_harness.dart
@@ -445,6 +445,8 @@
fileSystem: fileSystem,
sdk: sdk,
analytics: analytics,
+ // So we can test them.
+ enableScreenshots: true,
);
addTearDown(server.shutdown);
connection = client.connectServer(clientChannel);
diff --git a/pkgs/dart_mcp_server/test/tools/dtd_test.dart b/pkgs/dart_mcp_server/test/tools/dtd_test.dart
index bf92e23..491f013 100644
--- a/pkgs/dart_mcp_server/test/tools/dtd_test.dart
+++ b/pkgs/dart_mcp_server/test/tools/dtd_test.dart
@@ -32,27 +32,6 @@
});
group('flutter tests', () {
- test('can take a screenshot', () async {
- await testHarness.startDebugSession(
- counterAppPath,
- 'lib/main.dart',
- isFlutter: true,
- );
- final tools =
- (await testHarness.mcpServerConnection.listTools()).tools;
- final screenshotTool = tools.singleWhere(
- (t) => t.name == DartToolingDaemonSupport.screenshotTool.name,
- );
- final screenshotResult = await testHarness.callToolWithRetry(
- CallToolRequest(name: screenshotTool.name),
- );
- expect(screenshotResult.content.single, {
- 'data': anything,
- 'mimeType': 'image/png',
- 'type': ImageContent.expectedType,
- });
- });
-
test('can get the widget tree', () async {
await testHarness.startDebugSession(
counterAppPath,
@@ -225,6 +204,26 @@
});
});
+ test('can take a screenshot', () async {
+ await testHarness.startDebugSession(
+ counterAppPath,
+ 'lib/main.dart',
+ isFlutter: true,
+ );
+ final tools = (await testHarness.mcpServerConnection.listTools()).tools;
+ final screenshotTool = tools.singleWhere(
+ (t) => t.name == DartToolingDaemonSupport.screenshotTool.name,
+ );
+ final screenshotResult = await testHarness.callToolWithRetry(
+ CallToolRequest(name: screenshotTool.name),
+ );
+ expect(screenshotResult.content.single, {
+ 'data': anything,
+ 'mimeType': 'image/png',
+ 'type': ImageContent.expectedType,
+ });
+ });
+
group('get selected widget', () {
test('when a selected widget exists', () async {
final server = testHarness.serverConnectionPair.server!;
