feat(editor): Improve how we show default Agent prompt and Memory session parameters

packages/@n8n/nodes-langchain/nodes/agents/Agent/Agent.node.ts

@@ -21,7 +21,7 @@ import { sqlAgentAgentProperties } from './agents/SqlAgent/description';
 import { sqlAgentAgentExecute } from './agents/SqlAgent/execute';
 import { toolsAgentProperties } from './agents/ToolsAgent/description';
 import { toolsAgentExecute } from './agents/ToolsAgent/execute';
-import { promptTypeOptions, textInput } from '../../../utils/descriptions';
+import { promptTypeOptions, textFromPreviousNode, textInput } from '../../../utils/descriptions';
 
 // Function used in the inputs expression to figure out which inputs to
 // display based on the agent type
@@ -341,6 +341,17 @@ export class Agent implements INodeType {
 					},
 				},
 			},
+			{
+				...textFromPreviousNode,
+				displayOptions: {
+					show: { promptType: ['auto'], '@version': [{ _cnd: { gte: 1.7 } }] },
+					// SQL Agent has data source and credentials parameters so we need to include this input there manually
+					// to preserve the order
+					hide: {
+						agent: ['sqlAgent'],
+					},
+				},
+			},
 			{
 				...textInput,
 				displayOptions: {

packages/@n8n/nodes-langchain/nodes/agents/Agent/agents/SqlAgent/description.ts

@@ -1,6 +1,11 @@
 import type { INodeProperties } from 'n8n-workflow';
-import { promptTypeOptions, textInput } from '../../../../../utils/descriptions';
+
 import { SQL_PREFIX, SQL_SUFFIX } from './other/prompts';
+import {
+	promptTypeOptions,
+	textFromPreviousNode,
+	textInput,
+} from '../../../../../utils/descriptions';
 
 const dataSourceOptions: INodeProperties = {
 	displayName: 'Data Source',
@@ -114,6 +119,12 @@ export const sqlAgentAgentProperties: INodeProperties[] = [
 			},
 		},
 	},
+	{
+		...textFromPreviousNode,
+		displayOptions: {
+			show: { promptType: ['auto'], '@version': [{ _cnd: { gte: 1.7 } }], agent: ['sqlAgent'] },
+		},
+	},
 	{
 		...textInput,
 		displayOptions: {

packages/@n8n/nodes-langchain/nodes/agents/Agent/agents/SqlAgent/execute.ts

@@ -1,3 +1,9 @@
+import type { BaseChatMemory } from '@langchain/community/memory/chat_memory';
+import type { BaseLanguageModel } from '@langchain/core/language_models/base';
+import type { DataSource } from '@n8n/typeorm';
+import type { SqlCreatePromptArgs } from 'langchain/agents/toolkits/sql';
+import { SqlToolkit, createSqlAgent } from 'langchain/agents/toolkits/sql';
+import { SqlDatabase } from 'langchain/sql_db';
 import {
 	type IExecuteFunctions,
 	type INodeExecutionData,
@@ -6,19 +12,12 @@ import {
 	type IDataObject,
 } from 'n8n-workflow';
 
-import { SqlDatabase } from 'langchain/sql_db';
-import type { SqlCreatePromptArgs } from 'langchain/agents/toolkits/sql';
-import { SqlToolkit, createSqlAgent } from 'langchain/agents/toolkits/sql';
-import type { BaseLanguageModel } from '@langchain/core/language_models/base';
-import type { BaseChatMemory } from '@langchain/community/memory/chat_memory';
-import type { DataSource } from '@n8n/typeorm';
-
-import { getPromptInputByType, serializeChatHistory } from '../../../../../utils/helpers';
-import { getTracingConfig } from '../../../../../utils/tracing';
-import { getSqliteDataSource } from './other/handlers/sqlite';
+import { getMysqlDataSource } from './other/handlers/mysql';
 import { getPostgresDataSource } from './other/handlers/postgres';
+import { getSqliteDataSource } from './other/handlers/sqlite';
 import { SQL_PREFIX, SQL_SUFFIX } from './other/prompts';
-import { getMysqlDataSource } from './other/handlers/mysql';
+import { getPromptInputByType, serializeChatHistory } from '../../../../../utils/helpers';
+import { getTracingConfig } from '../../../../../utils/tracing';
 
 const parseTablesString = (tablesString: string) =>
 	tablesString

packages/@n8n/nodes-langchain/nodes/agents/OpenAiAssistant/OpenAiAssistant.node.ts

@@ -1,5 +1,5 @@
 import { AgentExecutor } from 'langchain/agents';
-import { OpenAI as OpenAIClient } from 'openai';
+import type { OpenAIToolType } from 'langchain/dist/experimental/openai_assistant/schema';
 import { OpenAIAssistantRunnable } from 'langchain/experimental/openai_assistant';
 import { NodeConnectionType, NodeOperationError } from 'n8n-workflow';
 import type {
@@ -8,10 +8,11 @@ import type {
 	INodeType,
 	INodeTypeDescription,
 } from 'n8n-workflow';
-import type { OpenAIToolType } from 'langchain/dist/experimental/openai_assistant/schema';
+import { OpenAI as OpenAIClient } from 'openai';
+
+import { formatToOpenAIAssistantTool } from './utils';
 import { getConnectedTools } from '../../../utils/helpers';
 import { getTracingConfig } from '../../../utils/tracing';
-import { formatToOpenAIAssistantTool } from './utils';
 
 export class OpenAiAssistant implements INodeType {
 	description: INodeTypeDescription = {

packages/@n8n/nodes-langchain/nodes/chains/ChainLLM/ChainLlm.node.ts

@@ -36,6 +36,7 @@ import {
 	getCustomErrorMessage as getCustomOpenAiErrorMessage,
 	isOpenAiError,
 } from '../../vendors/OpenAi/helpers/error-handling';
+import { promptTypeOptions, textFromPreviousNode } from '../../../utils/descriptions';
 
 interface MessagesTemplate {
 	type: string;
@@ -253,7 +254,7 @@ export class ChainLlm implements INodeType {
 		name: 'chainLlm',
 		icon: 'fa:link',
 		group: ['transform'],
-		version: [1, 1.1, 1.2, 1.3, 1.4],
+		version: [1, 1.1, 1.2, 1.3, 1.4, 1.5],
 		description: 'A simple chain to prompt a large language model',
 		defaults: {
 			name: 'Basic LLM Chain',
@@ -315,30 +316,16 @@ export class ChainLlm implements INodeType {
 				},
 			},
 			{
-				displayName: 'Prompt',
-				name: 'promptType',
-				type: 'options',
-				options: [
-					{
-						// eslint-disable-next-line n8n-nodes-base/node-param-display-name-miscased
-						name: 'Take from previous node automatically',
-						value: 'auto',
-						description: 'Looks for an input field called chatInput',
-					},
-					{
-						// eslint-disable-next-line n8n-nodes-base/node-param-display-name-miscased
-						name: 'Define below',
-						value: 'define',
-						description:
-							'Use an expression to reference data in previous nodes or enter static text',
-					},
-				],
+				...promptTypeOptions,
 				displayOptions: {
 					hide: {
 						'@version': [1, 1.1, 1.2, 1.3],
 					},
 				},
-				default: 'auto',
+			},
+			{
+				...textFromPreviousNode,
+				displayOptions: { show: { promptType: ['auto'], '@version': [{ _cnd: { gte: 1.5 } }] } },
 			},
 			{
 				displayName: 'Text',

packages/@n8n/nodes-langchain/nodes/chains/ChainRetrievalQA/ChainRetrievalQa.node.ts

@@ -1,3 +1,12 @@
+import type { BaseLanguageModel } from '@langchain/core/language_models/base';
+import {
+	ChatPromptTemplate,
+	SystemMessagePromptTemplate,
+	HumanMessagePromptTemplate,
+	PromptTemplate,
+} from '@langchain/core/prompts';
+import type { BaseRetriever } from '@langchain/core/retrievers';
+import { RetrievalQAChain } from 'langchain/chains';
 import {
 	NodeConnectionType,
 	type IExecuteFunctions,
@@ -7,20 +16,12 @@ import {
 	NodeOperationError,
 } from 'n8n-workflow';
 
-import { RetrievalQAChain } from 'langchain/chains';
-import type { BaseLanguageModel } from '@langchain/core/language_models/base';
-import type { BaseRetriever } from '@langchain/core/retrievers';
-import {
-	ChatPromptTemplate,
-	SystemMessagePromptTemplate,
-	HumanMessagePromptTemplate,
-	PromptTemplate,
-} from '@langchain/core/prompts';
-import { getTemplateNoticeField } from '../../../utils/sharedFields';
+import { promptTypeOptions, textFromPreviousNode } from '../../../utils/descriptions';
 import { getPromptInputByType, isChatInstance } from '../../../utils/helpers';
+import { getTemplateNoticeField } from '../../../utils/sharedFields';
 import { getTracingConfig } from '../../../utils/tracing';
 
-const SYSTEM_PROMPT_TEMPLATE = `Use the following pieces of context to answer the users question. 
+const SYSTEM_PROMPT_TEMPLATE = `Use the following pieces of context to answer the users question.
 If you don't know the answer, just say that you don't know, don't try to make up an answer.
 ----------------
 {context}`;
@@ -31,7 +32,7 @@ export class ChainRetrievalQa implements INodeType {
 		name: 'chainRetrievalQa',
 		icon: 'fa:link',
 		group: ['transform'],
-		version: [1, 1.1, 1.2, 1.3],
+		version: [1, 1.1, 1.2, 1.3, 1.4],
 		description: 'Answer questions about retrieved documents',
 		defaults: {
 			name: 'Question and Answer Chain',
@@ -108,30 +109,16 @@ export class ChainRetrievalQa implements INodeType {
 				},
 			},
 			{
-				displayName: 'Prompt',
-				name: 'promptType',
-				type: 'options',
-				options: [
-					{
-						// eslint-disable-next-line n8n-nodes-base/node-param-display-name-miscased
-						name: 'Take from previous node automatically',
-						value: 'auto',
-						description: 'Looks for an input field called chatInput',
-					},
-					{
-						// eslint-disable-next-line n8n-nodes-base/node-param-display-name-miscased
-						name: 'Define below',
-						value: 'define',
-						description:
-							'Use an expression to reference data in previous nodes or enter static text',
-					},
-				],
+				...promptTypeOptions,
 				displayOptions: {
 					hide: {
 						'@version': [{ _cnd: { lte: 1.2 } }],
 					},
 				},
-				default: 'auto',
+			},
+			{
+				...textFromPreviousNode,
+				displayOptions: { show: { promptType: ['auto'], '@version': [{ _cnd: { gte: 1.4 } }] } },
 			},
 			{
 				displayName: 'Text',

packages/@n8n/nodes-langchain/nodes/memory/MemoryBufferWindow/MemoryBufferWindow.node.ts

@@ -1,17 +1,23 @@
 /* eslint-disable n8n-nodes-base/node-dirname-against-convention */
+import type { BufferWindowMemoryInput } from 'langchain/memory';
+import { BufferWindowMemory } from 'langchain/memory';
 import {
 	NodeConnectionType,
 	type INodeType,
 	type INodeTypeDescription,
 	type ISupplyDataFunctions,
 	type SupplyData,
 } from 'n8n-workflow';
-import type { BufferWindowMemoryInput } from 'langchain/memory';
-import { BufferWindowMemory } from 'langchain/memory';
+
+import { getSessionId } from '../../../utils/helpers';
 import { logWrapper } from '../../../utils/logWrapper';
 import { getConnectionHintNoticeField } from '../../../utils/sharedFields';
-import { sessionIdOption, sessionKeyProperty, contextWindowLengthProperty } from '../descriptions';
-import { getSessionId } from '../../../utils/helpers';
+import {
+	sessionIdOption,
+	sessionKeyProperty,
+	contextWindowLengthProperty,
+	expressionSessionKeyProperty,
+} from '../descriptions';
 
 class MemoryChatBufferSingleton {
 	private static instance: MemoryChatBufferSingleton;
@@ -72,7 +78,7 @@ export class MemoryBufferWindow implements INodeType {
 		name: 'memoryBufferWindow',
 		icon: 'fa:database',
 		group: ['transform'],
-		version: [1, 1.1, 1.2],
+		version: [1, 1.1, 1.2, 1.3],
 		description: 'Stores in n8n memory, so no credentials required',
 		defaults: {
 			name: 'Window Buffer Memory',
@@ -129,6 +135,7 @@ export class MemoryBufferWindow implements INodeType {
 					},
 				},
 			},
+			expressionSessionKeyProperty(1.3),
 			sessionKeyProperty,
 			contextWindowLengthProperty,
 		],

packages/@n8n/nodes-langchain/nodes/memory/MemoryMotorhead/MemoryMotorhead.node.ts

@@ -1,4 +1,5 @@
 /* eslint-disable n8n-nodes-base/node-dirname-against-convention */
+import { MotorheadMemory } from '@langchain/community/memory/motorhead_memory';
 import {
 	NodeConnectionType,
 	type INodeType,
@@ -7,19 +8,18 @@ import {
 	type SupplyData,
 } from 'n8n-workflow';
 
-import { MotorheadMemory } from '@langchain/community/memory/motorhead_memory';
+import { getSessionId } from '../../../utils/helpers';
 import { logWrapper } from '../../../utils/logWrapper';
 import { getConnectionHintNoticeField } from '../../../utils/sharedFields';
-import { sessionIdOption, sessionKeyProperty } from '../descriptions';
-import { getSessionId } from '../../../utils/helpers';
+import { expressionSessionKeyProperty, sessionIdOption, sessionKeyProperty } from '../descriptions';
 
 export class MemoryMotorhead implements INodeType {
 	description: INodeTypeDescription = {
 		displayName: 'Motorhead',
 		name: 'memoryMotorhead',
 		icon: 'fa:file-export',
 		group: ['transform'],
-		version: [1, 1.1, 1.2],
+		version: [1, 1.1, 1.2, 1.3],
 		description: 'Use Motorhead Memory',
 		defaults: {
 			name: 'Motorhead',
@@ -82,6 +82,7 @@ export class MemoryMotorhead implements INodeType {
 					},
 				},
 			},
+			expressionSessionKeyProperty(1.3),
 			sessionKeyProperty,
 		],
 	};

packages/@n8n/nodes-langchain/nodes/memory/MemoryPostgresChat/MemoryPostgresChat.node.ts

@@ -1,29 +1,35 @@
 /* eslint-disable n8n-nodes-base/node-dirname-against-convention */
+import { PostgresChatMessageHistory } from '@langchain/community/stores/message/postgres';
+import { BufferMemory, BufferWindowMemory } from 'langchain/memory';
+import type { PostgresNodeCredentials } from 'n8n-nodes-base/dist/nodes/Postgres/v2/helpers/interfaces';
+import { postgresConnectionTest } from 'n8n-nodes-base/dist/nodes/Postgres/v2/methods/credentialTest';
+import { configurePostgres } from 'n8n-nodes-base/dist/nodes/Postgres/v2/transport';
 import type {
 	ISupplyDataFunctions,
 	INodeType,
 	INodeTypeDescription,
 	SupplyData,
 } from 'n8n-workflow';
 import { NodeConnectionType } from 'n8n-workflow';
-import { BufferMemory, BufferWindowMemory } from 'langchain/memory';
-import { PostgresChatMessageHistory } from '@langchain/community/stores/message/postgres';
 import type pg from 'pg';
-import { configurePostgres } from 'n8n-nodes-base/dist/nodes/Postgres/v2/transport';
-import type { PostgresNodeCredentials } from 'n8n-nodes-base/dist/nodes/Postgres/v2/helpers/interfaces';
-import { postgresConnectionTest } from 'n8n-nodes-base/dist/nodes/Postgres/v2/methods/credentialTest';
+
+import { getSessionId } from '../../../utils/helpers';
 import { logWrapper } from '../../../utils/logWrapper';
 import { getConnectionHintNoticeField } from '../../../utils/sharedFields';
-import { sessionIdOption, sessionKeyProperty, contextWindowLengthProperty } from '../descriptions';
-import { getSessionId } from '../../../utils/helpers';
+import {
+	sessionIdOption,
+	sessionKeyProperty,
+	contextWindowLengthProperty,
+	expressionSessionKeyProperty,
+} from '../descriptions';
 
 export class MemoryPostgresChat implements INodeType {
 	description: INodeTypeDescription = {
 		displayName: 'Postgres Chat Memory',
 		name: 'memoryPostgresChat',
 		icon: 'file:postgres.svg',
 		group: ['transform'],
-		version: [1, 1.1],
+		version: [1, 1.1, 1.2, 1.3],
 		description: 'Stores the chat history in Postgres table.',
 		defaults: {
 			name: 'Postgres Chat Memory',
@@ -56,6 +62,7 @@ export class MemoryPostgresChat implements INodeType {
 		properties: [
 			getConnectionHintNoticeField([NodeConnectionType.AiAgent]),
 			sessionIdOption,
+			expressionSessionKeyProperty(1.2),
 			sessionKeyProperty,
 			{
 				displayName: 'Table Name',