diff --git a/packages/core/src/utils/shell-utils.test.ts b/packages/core/src/utils/shell-utils.test.ts
index 9473dee7..22d316ad 100644
--- a/packages/core/src/utils/shell-utils.test.ts
+++ b/packages/core/src/utils/shell-utils.test.ts
@@ -38,7 +38,9 @@ describe('isCommandAllowed', () => {
     config.getCoreTools = () => ['ShellTool(ls -l)'];
     const result = isCommandAllowed('rm -rf /', config);
     expect(result.allowed).toBe(false);
-    expect(result.reason).toBe(`Command(s) not in the allowed commands list.`);
+    expect(result.reason).toBe(
+      `Command(s) not in the allowed commands list. Disallowed commands: "rm -rf /"`,
+    );
   });
 
   it('should block a command if it is in the blocked list', () => {
@@ -157,7 +159,7 @@ describe('checkCommandPermissions', () => {
       expect(result).toEqual({
         allAllowed: false,
         disallowedCommands: ['git status'],
-        blockReason: `Command(s) not in the allowed commands list.`,
+        blockReason: `Command(s) not in the allowed commands list. Disallowed commands: "git status"`,
         isHardDenial: false,
       });
     });
diff --git a/packages/core/src/utils/shell-utils.ts b/packages/core/src/utils/shell-utils.ts
index c7f1839e..4164cdca 100644
--- a/packages/core/src/utils/shell-utils.ts
+++ b/packages/core/src/utils/shell-utils.ts
@@ -301,7 +301,9 @@ export function checkCommandPermissions(
       return {
         allAllowed: false,
         disallowedCommands,
-        blockReason: `Command(s) not on the global or session allowlist.`,
+        blockReason: `Command(s) not on the global or session allowlist. Disallowed commands: ${disallowedCommands
+          .map((c) => JSON.stringify(c))
+          .join(', ')}`,
         isHardDenial: false, // This is a soft denial; confirmation is possible.
       };
     }
@@ -322,7 +324,7 @@ export function checkCommandPermissions(
         return {
           allAllowed: false,
           disallowedCommands,
-          blockReason: `Command(s) not in the allowed commands list.`,
+          blockReason: `Command(s) not in the allowed commands list. Disallowed commands: ${disallowedCommands.map((c) => JSON.stringify(c)).join(', ')}`,
           isHardDenial: false, // This is a soft denial.
         };
       }