fix: hide internal tool-result file reads from sidebar activity

Claude reads its own ~/.claude/projects/.../tool-results/ files as
internal plumbing. These showed up as long unreadable paths in the
sidebar. Now: describeToolCall returns empty for tool-result reads,
and the sidebar skips rendering tool_use entries with no description.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

browse/src/sidebar-agent.ts

@@ -167,7 +167,11 @@ function describeToolCall(tool: string, input: any): string {
     return short.length > 100 ? short.slice(0, 100) + '…' : short;
   }
 
-  if (tool === 'Read' && input.file_path) return `Reading ${shorten(input.file_path)}`;
+  if (tool === 'Read' && input.file_path) {
+    // Skip Claude's internal tool-result file reads — they're plumbing, not user-facing
+    if (input.file_path.includes('/tool-results/') || input.file_path.includes('/.claude/projects/')) return '';
+    return `Reading ${shorten(input.file_path)}`;
+  }
   if (tool === 'Edit' && input.file_path) return `Editing ${shorten(input.file_path)}`;
   if (tool === 'Write' && input.file_path) return `Writing ${shorten(input.file_path)}`;
   if (tool === 'Grep' && input.pattern) return `Searching for "${input.pattern}"`;

extension/sidepanel.js

@@ -241,11 +241,15 @@ function handleAgentEvent(entry) {
   if (thinking) thinking.remove();
 
   if (entry.type === 'tool_use') {
-    const toolEl = document.createElement('div');
-    toolEl.className = 'agent-tool';
     const toolName = entry.tool || 'Tool';
     const toolInput = entry.input || '';
 
+    // Skip tool uses with no description (e.g. internal tool-result file reads)
+    if (!toolInput) return;
+
+    const toolEl = document.createElement('div');
+    toolEl.className = 'agent-tool';
+
     // Use the verbose description as the primary text
     // The tool name becomes a subtle badge
     const toolIcon = toolName === 'Bash' ? '▸' : toolName === 'Read' ? '📄' : toolName === 'Grep' ? '🔍' : toolName === 'Glob' ? '📁' : '⚡';