fix(OpenAI Node, Basic LLM Chain Node, Tool Agent Node): Better OpenAI API rate limit errors (#10797)

packages/@n8n/nodes-langchain/nodes/llms/LMChatOpenAi/LmChatOpenAi.node.ts

@@ -5,11 +5,15 @@ import {
 	type INodeType,
 	type INodeTypeDescription,
 	type SupplyData,
+	type JsonObject,
+	NodeApiError,
 } from 'n8n-workflow';
 
 import { ChatOpenAI, type ClientOptions } from '@langchain/openai';
 import { getConnectionHintNoticeField } from '../../../utils/sharedFields';
 import { N8nLlmTracing } from '../N8nLlmTracing';
+import { RateLimitError } from 'openai';
+import { getCustomErrorMessage } from '../../vendors/OpenAi/helpers/error-handling';
 
 export class LmChatOpenAi implements INodeType {
 	description: INodeTypeDescription = {
@@ -272,6 +276,25 @@ export class LmChatOpenAi implements INodeType {
 						response_format: { type: options.responseFormat },
 					}
 				: undefined,
+			onFailedAttempt: (error: any) => {
+				// If the error is a rate limit error, we want to handle it differently
+				// because OpenAI has multiple different rate limit errors
+				if (error instanceof RateLimitError) {
+					const errorCode = error?.code;
+					if (errorCode) {
+						const customErrorMessage = getCustomErrorMessage(errorCode);
+
+						const apiError = new NodeApiError(this.getNode(), error as unknown as JsonObject);
+						if (customErrorMessage) {
+							apiError.message = customErrorMessage;
+						}
+
+						throw apiError;
+					}
+				}
+
+				throw error;
+			},
 		});
 
 		return {