diff --git a/packages/core/src/tools/shell.ts b/packages/core/src/tools/shell.ts
index 3bd7d754..1265aee7 100644
--- a/packages/core/src/tools/shell.ts
+++ b/packages/core/src/tools/shell.ts
@@ -419,6 +419,11 @@ export class ShellTool extends BaseDeclarativeTool<
             type: 'string',
             description: getCommandDescription(),
           },
+          is_background: {
+            type: 'boolean',
+            description:
+              'Whether to run the command in background. Default is false. Set to true for long-running processes like development servers, watchers, or daemons that should continue running without blocking further commands.',
+          },
           description: {
             type: 'string',
             description:
diff --git a/packages/core/src/utils/schemaValidator.ts b/packages/core/src/utils/schemaValidator.ts
index 3b009fc8..febe44b0 100644
--- a/packages/core/src/utils/schemaValidator.ts
+++ b/packages/core/src/utils/schemaValidator.ts
@@ -14,7 +14,6 @@ const ajValidator = new AjvClass({ coerceTypes: true });
 const addFormatsFunc = (addFormats as any).default || addFormats;
 addFormatsFunc(ajValidator);
 
-
 /**
  * Simple utility to validate objects against JSON Schemas
  */