1 files changed, 2 insertions, 2 deletions
diff --git a/packages/core/src/tools/tool-registry.ts b/packages/core/src/tools/tool-registry.ts
index 21aec687..12aa1a83 100644
--- a/packages/core/src/tools/tool-registry.ts
+++ b/packages/core/src/tools/tool-registry.ts
@@ -56,10 +56,10 @@ Signal: Signal number or \`(none)\` if no signal was received.
     let stdout = '';
     let stderr = '';
     child.stdout.on('data', (data) => {
-      stdout += data.toString();
+      stdout += data?.toString();
     });
     child.stderr.on('data', (data) => {
-      stderr += data.toString();
+      stderr += data?.toString();
     });
     let error: Error | null = null;
     child.on('error', (err: Error) => {