feat: gate screencast tools behind --experimental-screencast flag

Screencast tools (screencast_start, screencast_stop) are now only registered when the --experimental-screencast CLI flag is provided, following the existing experimental conditions pattern used by --experimental-vision.

Author: dobesv

src/cli.ts

@@ -173,6 +173,11 @@ export const cliOptions = {
     describe: 'Whether to enable interoperability tools',
     hidden: true,
   },
+  experimentalScreencast: {
+    type: 'boolean',
+    describe: 'Whether to enable screencast tools',
+    hidden: true,
+  },
   chromeArg: {
     type: 'array',
     describe:

src/main.ts

@@ -182,6 +182,12 @@ function registerTool(tool: ToolDefinition): void {
   ) {
     return;
   }
+  if (
+    tool.annotations.conditions?.includes('screencast') &&
+    !args.experimentalScreencast
+  ) {
+    return;
+  }
   server.registerTool(
     tool.name,
     {

src/tools/screencast.ts

@@ -27,6 +27,7 @@ export const startScreencast = defineTool({
   annotations: {
     category: ToolCategory.DEBUGGING,
     readOnlyHint: false,
+    conditions: ['screencast'],
   },
   schema: {
     filePath: zod
@@ -114,6 +115,7 @@ export const stopScreencast = defineTool({
   annotations: {
     category: ToolCategory.DEBUGGING,
     readOnlyHint: false,
+    conditions: ['screencast'],
   },
   schema: {},
   handler: async (_request, response, context) => {