Bugfix/Buffer Memory for Anthropic (#3242)

fix buffer memory

packages/components/nodes/memory/ConversationSummaryBufferMemory/ConversationSummaryBufferMemory.ts

@@ -10,9 +10,10 @@ import {
 } from '../../../src/Interface'
 import { getBaseClasses, mapChatMessageToBaseMessage } from '../../../src/utils'
 import { BaseLanguageModel } from '@langchain/core/language_models/base'
-import { BaseMessage, getBufferString } from '@langchain/core/messages'
+import { BaseMessage, getBufferString, HumanMessage } from '@langchain/core/messages'
 import { ConversationSummaryBufferMemory, ConversationSummaryBufferMemoryInput } from 'langchain/memory'
 import { DataSource } from 'typeorm'
+import { ChatAnthropic } from '../../chatmodels/ChatAnthropic/FlowiseChatAnthropic'
 
 class ConversationSummaryBufferMemory_Memory implements INode {
     label: string
@@ -163,7 +164,12 @@ class ConversationSummaryBufferMemoryExtended extends FlowiseSummaryBufferMemory
         // ----------- Finished Pruning ---------------
 
         if (this.movingSummaryBuffer) {
-            baseMessages = [new this.summaryChatMessageClass(this.movingSummaryBuffer), ...baseMessages]
+            // Anthropic doesn't support multiple system messages
+            if (this.llm instanceof ChatAnthropic) {
+                baseMessages = [new HumanMessage(`Below is the summarized conversation:\n\n${this.movingSummaryBuffer}`), ...baseMessages]
+            } else {
+                baseMessages = [new this.summaryChatMessageClass(this.movingSummaryBuffer), ...baseMessages]
+            }
         }
 
         if (returnBaseMessages) {