diff --git a/assistant/src/browser/operations.ts b/assistant/src/browser/operations.ts
index bac21bb10cc..6e653603717 100644
--- a/assistant/src/browser/operations.ts
+++ b/assistant/src/browser/operations.ts
@@ -196,7 +196,8 @@ const DISPATCH_HANDLERS: Record<BrowserOperation, OperationHandler> = {
  * @param input     - Flat input object matching the operation's field schema.
  * @param context   - Tool execution context (conversation ID, signal, etc.).
  * @returns The tool execution result from the underlying handler.
- * @throws If the operation identifier is not recognized.
+ *   If the operation identifier is not recognized, returns an error
+ *   result (`isError: true`) rather than throwing.
  */
 export async function executeBrowserOperation(
   operation: BrowserOperation,
@@ -220,8 +221,8 @@ export async function executeBrowserOperation(
  * constraints. Used by the CLI command builder to generate subcommands.
  *
  * The `browser_mode` and `activity` fields are omitted from per-operation
- * metadata because they are common to all operations and handled by the
- * CLI framework as global options.
+ * metadata because they are not exposed through the CLI. Operations
+ * invoked via the CLI always use the default browser mode.
  */
 export const BROWSER_OPERATION_META: readonly BrowserOperationMeta[] = [
   {
diff --git a/assistant/src/cli/commands/browser.ts b/assistant/src/cli/commands/browser.ts
index cda13760330..5f70da54f5e 100644
--- a/assistant/src/cli/commands/browser.ts
+++ b/assistant/src/cli/commands/browser.ts
@@ -154,6 +154,9 @@ function buildSubcommand(parent: Command, meta: BrowserOperationMeta): void {
       }
     }
 
+    // Browser operations can be long-running (page loads, auth
+    // challenges, downloads up to 120s, etc.), so use a generous
+    // IPC timeout that exceeds any server-side operation timeout.
     const ipcResult = await cliIpcCall<BrowserExecuteResult>(
       "browser_execute",
       {
@@ -161,6 +164,7 @@ function buildSubcommand(parent: Command, meta: BrowserOperationMeta): void {
         input,
         sessionId,
       },
+      { timeoutMs: 180_000 },
     );
 
     if (!ipcResult.ok) {