diff --git a/src/components/Messages.tsx b/src/components/Messages.tsx
index 638fe6c42..c7d4eb671 100644
--- a/src/components/Messages.tsx
+++ b/src/components/Messages.tsx
@@ -1,5 +1,6 @@
 import { feature } from 'bun:bundle';
 import chalk from 'chalk';
+import { SentryErrorBoundary } from './SentryErrorBoundary.js';
 import type { UUID } from 'crypto';
 import type { RefObject } from 'react';
 import * as React from 'react';
@@ -890,7 +891,7 @@ const MessagesImpl = ({
   );
 
   return (
-    <>
+    <SentryErrorBoundary name="MessagesBoundary">
       {/* Logo */}
       {!hideLogo && !(renderRange && renderRange[0] > 0) && <LogoHeader agentDefinitions={agentDefinitions} />}
 
@@ -977,7 +978,7 @@ const MessagesImpl = ({
           />
         </Box>
       )}
-    </>
+    </SentryErrorBoundary>
   );
 };
 
diff --git a/src/components/SentryErrorBoundary.ts b/src/components/SentryErrorBoundary.ts
deleted file mode 100644
index 7380a62b0..000000000
--- a/src/components/SentryErrorBoundary.ts
+++ /dev/null
@@ -1,38 +0,0 @@
-import * as React from 'react'
-import { captureException } from 'src/utils/sentry.js'
-
-interface Props {
-  children: React.ReactNode
-  /** Optional label for identifying which component boundary caught the error */
-  name?: string
-}
-
-interface State {
-  hasError: boolean
-}
-
-export class SentryErrorBoundary extends React.Component<Props, State> {
-  constructor(props: Props) {
-    super(props)
-    this.state = { hasError: false }
-  }
-
-  static getDerivedStateFromError(): State {
-    return { hasError: true }
-  }
-
-  componentDidCatch(error: Error, errorInfo: React.ErrorInfo): void {
-    captureException(error, {
-      componentBoundary: this.props.name || 'SentryErrorBoundary',
-      componentStack: errorInfo.componentStack,
-    })
-  }
-
-  render(): React.ReactNode {
-    if (this.state.hasError) {
-      return null
-    }
-
-    return this.props.children
-  }
-}
diff --git a/src/components/SentryErrorBoundary.tsx b/src/components/SentryErrorBoundary.tsx
new file mode 100644
index 000000000..a1a7ace0e
--- /dev/null
+++ b/src/components/SentryErrorBoundary.tsx
@@ -0,0 +1,62 @@
+import * as React from 'react';
+import { Box, Text } from '@anthropic/ink';
+import { captureException } from 'src/utils/sentry.js';
+import { logError } from 'src/utils/log.js';
+
+interface Props {
+  children: React.ReactNode;
+  /** Optional label for identifying which component boundary caught the error */
+  name?: string;
+}
+
+interface State {
+  hasError: boolean;
+  error: Error | null;
+  errorInfo: React.ErrorInfo | null;
+}
+
+export class SentryErrorBoundary extends React.Component<Props, State> {
+  constructor(props: Props) {
+    super(props);
+    this.state = { hasError: false, error: null, errorInfo: null };
+  }
+
+  static getDerivedStateFromError(error: Error): Pick<State, 'hasError' | 'error'> {
+    return { hasError: true, error };
+  }
+
+  componentDidCatch(error: Error, errorInfo: React.ErrorInfo): void {
+    this.setState({ errorInfo });
+
+    // Log to stderr so the diagnostic info is visible even in production builds
+    const boundary = this.props.name || 'SentryErrorBoundary';
+    const lines = ['', `[ErrorBoundary:${boundary}] React rendering error caught`, `  Message: ${error.message}`];
+    if (errorInfo.componentStack) {
+      lines.push(`  Component stack:\n${errorInfo.componentStack}`);
+    }
+    // eslint-disable-next-line no-console -- intentional stderr diagnostic output
+    console.error(lines.join('\n'));
+
+    logError(error);
+    captureException(error, {
+      componentBoundary: boundary,
+      componentStack: errorInfo.componentStack,
+    });
+  }
+
+  render(): React.ReactNode {
+    if (this.state.hasError) {
+      return (
+        <Box flexDirection="column" paddingX={1} paddingY={1}>
+          <Text color="error" bold>
+            React Rendering Error
+          </Text>
+          <Text color="error">{this.state.error?.message}</Text>
+          {this.props.name && <Text dimColor>Boundary: {this.props.name}</Text>}
+        </Box>
+      );
+    }
+
+    return this.props.children;
+  }
+}
diff --git a/src/replLauncher.tsx b/src/replLauncher.tsx
index 0d27afe12..040636719 100644
--- a/src/replLauncher.tsx
+++ b/src/replLauncher.tsx
@@ -18,11 +18,14 @@ export async function launchRepl(
   renderAndRun: (root: Root, element: React.ReactNode) => Promise<void>,
 ): Promise<void> {
   const { App } = await import('./components/App.js');
+  const { SentryErrorBoundary } = await import('./components/SentryErrorBoundary.js');
   const { REPL } = await import('./screens/REPL.js');
   await renderAndRun(
     root,
-    <App {...appProps}>
-      <REPL {...replProps} />
-    </App>,
+    <SentryErrorBoundary name="RootREPLBoundary">
+      <App {...appProps}>
+        <REPL {...replProps} />
+      </App>
+    </SentryErrorBoundary>,
   );
 }