fix: show Claude tool result errors

Claude stores some tool failures as errored tool_result rows. The UI either
attached those rows to hidden tool output or dropped them when no matching tool
call was rendered, which made validation failures disappear from chat history.

Render unattached errored tool results, unwrap Claude tool_use_error content,
and keep tool errors visible even for tools whose successful output is hidden.
Also remove the permission-grant recovery controls from rendered error history
so denied tool use stays a plain error message.

src/components/chat/hooks/useChatMessages.ts

@@ -7,6 +7,12 @@ import type { NormalizedMessage } from '../../../stores/useSessionStore';
 import type { ChatMessage, SubagentChildTool } from '../types/types';
 import { decodeHtmlEntities, unescapeWithMathProtection, formatUsageLimitText } from '../utils/chatFormatting';
 
+function formatToolResultContent(content: unknown): string {
+  const text = typeof content === 'string' ? content : JSON.stringify(content);
+  const toolUseErrorMatch = /^<tool_use_error>([\s\S]*)<\/tool_use_error>$/.exec(text.trim());
+  return toolUseErrorMatch ? toolUseErrorMatch[1] : text;
+}
+
 /**
  * Convert NormalizedMessage[] from the session store into ChatMessage[]
  * that the existing UI components expect.
@@ -20,7 +26,12 @@ export function normalizedToChatMessages(messages: NormalizedMessage[]): ChatMes
 
   // First pass: collect tool results for attachment
   const toolResultMap = new Map<string, NormalizedMessage>();
+  const toolUseIds = new Set<string>();
   for (const msg of messages) {
+    if (msg.kind === 'tool_use' && msg.toolId) {
+      toolUseIds.add(msg.toolId);
+    }
+
     if (msg.kind === 'tool_result' && msg.toolId) {
       toolResultMap.set(msg.toolId, msg);
     }
@@ -97,7 +108,7 @@ export function normalizedToChatMessages(messages: NormalizedMessage[]): ChatMes
 
         const toolResult = tr
           ? {
-              content: typeof tr.content === 'string' ? tr.content : JSON.stringify(tr.content),
+              content: formatToolResultContent(tr.content),
               isError: Boolean(tr.isError),
               toolUseResult: (tr as any).toolUseResult,
             }
@@ -191,8 +202,25 @@ export function normalizedToChatMessages(messages: NormalizedMessage[]): ChatMes
         break;
 
       // tool_result is handled via attachment to tool_use above
-      case 'tool_result':
+      case 'tool_result': {
+        if (msg.toolId && toolUseIds.has(msg.toolId)) {
+          break;
+        }
+
+        const content = formatToolResultContent(msg.content || '');
+        if (!content.trim()) {
+          break;
+        }
+
+        converted.push({
+          type: msg.isError ? 'error' : 'assistant',
+          content,
+          timestamp: msg.timestamp,
+          toolId: msg.toolId,
+          ...sharedMetadata,
+        });
         break;
+      }
 
       default:
         break;

src/components/chat/tools/configs/toolConfigs.ts

@@ -564,11 +564,15 @@ export function shouldHideToolResult(toolName: string, toolResult: any): boolean
 
   if (!config.result) return false;
 
+  // Hidden/success-only configs suppress noisy successful output, but errors
+  // still need to be visible so failed tool calls are diagnosable.
+  if (toolResult?.isError) return false;
+
   // Always hidden
   if (config.result.hidden) return true;
 
   // Hide on success only
-  if (config.result.hideOnSuccess && toolResult && !toolResult.isError) {
+  if (config.result.hideOnSuccess && toolResult) {
     return true;
   }
 

src/components/chat/view/subcomponents/MessageComponent.tsx

@@ -1,5 +1,6 @@
 import { memo, useEffect, useMemo, useRef, useState } from 'react';
 import { useTranslation } from 'react-i18next';
+
 import SessionProviderLogo from '../../../llm-logo-provider/SessionProviderLogo';
 import type {
   ChatMessage,
@@ -8,10 +9,10 @@ import type {
   Provider,
 } from '../../types/types';
 import { formatUsageLimitText } from '../../utils/chatFormatting';
-import { getClaudePermissionSuggestion } from '../../utils/chatPermissions';
 import type { Project } from '../../../../types/app';
 import { ToolRenderer, shouldHideToolResult } from '../../tools';
 import { Reasoning, ReasoningTrigger, ReasoningContent } from '../../../../shared/view/ui';
+
 import { Markdown } from './Markdown';
 import MessageCopyControl from './MessageCopyControl';
 
@@ -41,10 +42,9 @@ type InteractiveOption = {
   isSelected: boolean;
 };
 
-type PermissionGrantState = 'idle' | 'granted' | 'error';
 const COPY_HIDDEN_TOOL_NAMES = new Set(['Bash', 'Edit', 'Write', 'ApplyPatch']);
 
-const MessageComponent = memo(({ message, prevMessage, createDiff, onFileOpen, onShowSettings, onGrantToolPermission, autoExpandTools, showRawParameters, showThinking, selectedProject, provider }: MessageComponentProps) => {
+const MessageComponent = memo(({ message, prevMessage, createDiff, onFileOpen, autoExpandTools, showRawParameters, showThinking, selectedProject, provider }: MessageComponentProps) => {
   const { t } = useTranslation('chat');
   const isGrouped = prevMessage && prevMessage.type === message.type &&
     ((prevMessage.type === 'assistant') ||
@@ -53,8 +53,6 @@ const MessageComponent = memo(({ message, prevMessage, createDiff, onFileOpen, o
       (prevMessage.type === 'error'));
   const messageRef = useRef<HTMLDivElement | null>(null);
   const [isExpanded, setIsExpanded] = useState(false);
-  const permissionSuggestion = getClaudePermissionSuggestion(message, provider);
-  const [permissionGrantState, setPermissionGrantState] = useState<PermissionGrantState>('idle');
   const userCopyContent = String(message.content || '');
   const formattedMessageContent = useMemo(
     () => formatUsageLimitText(String(message.content || '')),
@@ -73,10 +71,6 @@ const MessageComponent = memo(({ message, prevMessage, createDiff, onFileOpen, o
     !message.isThinking;
 
 
-  useEffect(() => {
-    setPermissionGrantState('idle');
-  }, [permissionSuggestion?.entry, message.toolId]);
-
   useEffect(() => {
     const node = messageRef.current;
     if (!autoExpandTools || !node || !message.isToolUse) return;
@@ -241,55 +235,6 @@ const MessageComponent = memo(({ message, prevMessage, createDiff, onFileOpen, o
                         <Markdown className="prose prose-sm prose-red max-w-none dark:prose-invert">
                           {String(message.toolResult.content || '')}
                         </Markdown>
-                        {permissionSuggestion && (
-                          <div className="mt-4 border-t border-red-200/60 pt-3 dark:border-red-800/60">
-                            <div className="flex flex-wrap items-center gap-2">
-                              <button
-                                type="button"
-                                onClick={() => {
-                                  if (!onGrantToolPermission) return;
-                                  const result = onGrantToolPermission(permissionSuggestion);
-                                  if (result?.success) {
-                                    setPermissionGrantState('granted');
-                                  } else {
-                                    setPermissionGrantState('error');
-                                  }
-                                }}
-                                disabled={permissionSuggestion.isAllowed || permissionGrantState === 'granted'}
-                                className={`inline-flex items-center gap-2 rounded-md border px-3 py-1.5 text-xs font-medium transition-colors ${permissionSuggestion.isAllowed || permissionGrantState === 'granted'
-                                  ? 'cursor-default border-green-300/70 bg-green-100 text-green-800 dark:border-green-800/60 dark:bg-green-900/30 dark:text-green-200'
-                                  : 'border-red-300/70 bg-white/80 text-red-700 hover:bg-white dark:border-red-800/60 dark:bg-gray-900/40 dark:text-red-200 dark:hover:bg-gray-900/70'
-                                  }`}
-                              >
-                                {permissionSuggestion.isAllowed || permissionGrantState === 'granted'
-                                  ? t('permissions.added')
-                                  : t('permissions.grant', { tool: permissionSuggestion.toolName })}
-                              </button>
-                              {onShowSettings && (
-                                <button
-                                  type="button"
-                                  onClick={(e) => { e.stopPropagation(); onShowSettings(); }}
-                                  className="text-xs text-red-700 underline hover:text-red-800 dark:text-red-200 dark:hover:text-red-100"
-                                >
-                                  {t('permissions.openSettings')}
-                                </button>
-                              )}
-                            </div>
-                            <div className="mt-2 text-xs text-red-700/90 dark:text-red-200/80">
-                              {t('permissions.addTo', { entry: permissionSuggestion.entry })}
-                            </div>
-                            {permissionGrantState === 'error' && (
-                              <div className="mt-2 text-xs text-red-700 dark:text-red-200">
-                                {t('permissions.error')}
-                              </div>
-                            )}
-                            {(permissionSuggestion.isAllowed || permissionGrantState === 'granted') && (
-                              <div className="mt-2 text-xs text-green-700 dark:text-green-200">
-                                {t('permissions.retry')}
-                              </div>
-                            )}
-                          </div>
-                        )}
                       </div>
                     </div>
                   ) : (