Desktop: Fixes #16783: Fix AI chat counting tool results twice towards the size limit (#16784)

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

packages/lib/services/ai/noteChat.test.ts

@@ -1,5 +1,5 @@
 import { _internal, ChatCommands, runNoteChat } from './noteChat';
-import { ChatRole, ChatToolCall } from './types';
+import { ChatRole, ChatToolCall, ChatToolMessage } from './types';
 import { expectThrow, setupDatabase, switchClient, withWarningSilenced } from '../../testing/test-utils';
 import Setting from '../../models/Setting';
 import { NoteContext } from './tools/types';
@@ -159,6 +159,20 @@ describe('noteChat', () => {
 		}, 'aiNoteTooLarge');
 	});
 
+	test('assertWithinTokenBudget should count tool results once', async () => {
+		const toolResult = (content: string): ChatToolMessage => ({
+			role: ChatRole.Tool, content, toolName: 'editor_readNoteBody', toolCallId: 'call-1', userDescription: '', isEdit: false, isError: false,
+		});
+
+		// About 75 tokens
+		_internal.assertWithinTokenBudget([toolResult('Testing... '.repeat(27))], 100);
+
+		await expectThrow(async () => {
+			// About 125 tokens
+			_internal.assertWithinTokenBudget([toolResult('Testing... '.repeat(45))], 100);
+		}, 'aiNoteTooLarge');
+	});
+
 	test('runTools should describe successful edit operations', async () => {
 		const toolCalls: ChatToolCall[] = [
 			{ toolName: 'editor_appendToNote', callId: 'call-1', arguments: { text: 'Test.' }, parseError: null },

packages/lib/services/ai/noteChat.ts

@@ -241,9 +241,6 @@ const assertWithinTokenBudget = (history: ChatMessage[], budget: number) => {
 		if (message.role === ChatRole.Assistant) {
 			totalTokens += estimateToolCallTokens(message.toolCalls ?? []);
 		}
-		if (message.role === ChatRole.Tool) {
-			totalTokens += estimateTokens(message.content);
-		}
 	}
 
 	if (totalTokens > budget) {