{"version":3,"file":"index.cjs","names":["Agent","StructuredChatOutputParserWithRetries","PREFIX","SUFFIX","SystemMessagePromptTemplate","PromptTemplate","FORMAT_INSTRUCTIONS","HumanMessagePromptTemplate","ChatPromptTemplate","LLMChain","isOpenAITool","isStructuredTool","renderTextDescriptionAndArgs","AgentRunnableSequence","RunnablePassthrough","formatLogToString"],"sources":["../../../src/agents/structured_chat/index.ts"],"sourcesContent":["import type { StructuredToolInterface } from \"@langchain/core/tools\";\nimport {\n isOpenAITool,\n type BaseLanguageModel,\n type BaseLanguageModelInterface,\n type ToolDefinition,\n} from \"@langchain/core/language_models/base\";\nimport { RunnablePassthrough } from \"@langchain/core/runnables\";\nimport type { BasePromptTemplate } from \"@langchain/core/prompts\";\nimport {\n BaseMessagePromptTemplate,\n ChatPromptTemplate,\n HumanMessagePromptTemplate,\n SystemMessagePromptTemplate,\n PromptTemplate,\n} from \"@langchain/core/prompts\";\nimport { AgentStep } from \"@langchain/core/agents\";\nimport { isStructuredTool } from \"@langchain/core/utils/function_calling\";\nimport { isInteropZodSchema } from \"@langchain/core/utils/types\";\nimport {\n type JsonSchema7Type,\n toJsonSchema,\n} from \"@langchain/core/utils/json_schema\";\nimport { LLMChain } from \"../../chains/llm_chain.js\";\nimport { Optional } from \"../../types/type-utils.js\";\nimport {\n Agent,\n AgentArgs,\n AgentRunnableSequence,\n OutputParserArgs,\n} from \"../agent.js\";\nimport { AgentInput } from \"../types.js\";\nimport { StructuredChatOutputParserWithRetries } from \"./outputParser.js\";\nimport { FORMAT_INSTRUCTIONS, PREFIX, SUFFIX } from \"./prompt.js\";\nimport { renderTextDescriptionAndArgs } from \"../../tools/render.js\";\nimport { formatLogToString } from \"../format_scratchpad/log.js\";\n\n/**\n * Interface for arguments used to create a prompt for a\n * StructuredChatAgent.\n */\nexport interface StructuredChatCreatePromptArgs {\n /** String to put after the list of tools. */\n suffix?: string;\n /** String to put before the list of tools. */\n prefix?: string;\n /** String to use directly as the human message template. */\n humanMessageTemplate?: string;\n /** List of input variables the final prompt will expect. */\n inputVariables?: string[];\n /** List of historical prompts from memory. */\n memoryPrompts?: BaseMessagePromptTemplate[];\n}\n\n/**\n * Type for input data for creating a StructuredChatAgent, with the\n * 'outputParser' property made optional.\n */\nexport type StructuredChatAgentInput = Optional;\n\n/**\n * Agent that interoperates with Structured Tools using React logic.\n * @augments Agent\n */\nexport class StructuredChatAgent extends Agent {\n static lc_name() {\n return \"StructuredChatAgent\";\n }\n\n lc_namespace = [\"langchain\", \"agents\", \"structured_chat\"];\n\n constructor(input: StructuredChatAgentInput) {\n const outputParser =\n input?.outputParser ?? StructuredChatAgent.getDefaultOutputParser();\n super({ ...input, outputParser });\n }\n\n _agentType() {\n return \"structured-chat-zero-shot-react-description\" as const;\n }\n\n observationPrefix() {\n return \"Observation: \";\n }\n\n llmPrefix() {\n return \"Thought:\";\n }\n\n _stop(): string[] {\n return [\"Observation:\"];\n }\n\n /**\n * Validates that all provided tools have a description. Throws an error\n * if any tool lacks a description.\n * @param tools Array of StructuredTool instances to validate.\n */\n static validateTools(tools: StructuredToolInterface[]) {\n const descriptionlessTool = tools.find((tool) => !tool.description);\n if (descriptionlessTool) {\n const msg =\n `Got a tool ${descriptionlessTool.name} without a description.` +\n ` This agent requires descriptions for all tools.`;\n throw new Error(msg);\n }\n }\n\n /**\n * Returns a default output parser for the StructuredChatAgent. If an LLM\n * is provided, it creates an output parser with retry logic from the LLM.\n * @param fields Optional fields to customize the output parser. Can include an LLM and a list of tool names.\n * @returns An instance of StructuredChatOutputParserWithRetries.\n */\n static getDefaultOutputParser(\n fields?: OutputParserArgs & {\n toolNames: string[];\n }\n ) {\n if (fields?.llm) {\n return StructuredChatOutputParserWithRetries.fromLLM(fields.llm, {\n toolNames: fields.toolNames,\n });\n }\n return new StructuredChatOutputParserWithRetries({\n toolNames: fields?.toolNames,\n });\n }\n\n /**\n * Constructs the agent's scratchpad from a list of steps. If the agent's\n * scratchpad is not empty, it prepends a message indicating that the\n * agent has not seen any previous work.\n * @param steps Array of AgentStep instances to construct the scratchpad from.\n * @returns A Promise that resolves to a string representing the agent's scratchpad.\n */\n async constructScratchPad(steps: AgentStep[]): Promise {\n const agentScratchpad = await super.constructScratchPad(steps);\n if (agentScratchpad) {\n return `This was your previous work (but I haven't seen any of it! I only see what you return as final answer):\\n${agentScratchpad}`;\n }\n return agentScratchpad;\n }\n\n /**\n * Creates a string representation of the schemas of the provided tools.\n * @param tools Array of StructuredTool instances to create the schemas string from.\n * @returns A string representing the schemas of the provided tools.\n */\n static createToolSchemasString(tools: StructuredToolInterface[]) {\n return tools\n .map((tool) => {\n const jsonSchema = (\n isInteropZodSchema(tool.schema)\n ? toJsonSchema(tool.schema)\n : tool.schema\n ) as { properties?: Record } | undefined;\n return `${tool.name}: ${tool.description}, args: ${JSON.stringify(\n jsonSchema?.properties\n )}`;\n })\n .join(\"\\n\");\n }\n\n /**\n * Create prompt in the style of the agent.\n *\n * @param tools - List of tools the agent will have access to, used to format the prompt.\n * @param args - Arguments to create the prompt with.\n * @param args.suffix - String to put after the list of tools.\n * @param args.prefix - String to put before the list of tools.\n * @param args.inputVariables List of input variables the final prompt will expect.\n * @param args.memoryPrompts List of historical prompts from memory.\n */\n static createPrompt(\n tools: StructuredToolInterface[],\n args?: StructuredChatCreatePromptArgs\n ) {\n const {\n prefix = PREFIX,\n suffix = SUFFIX,\n inputVariables = [\"input\", \"agent_scratchpad\"],\n humanMessageTemplate = \"{input}\\n\\n{agent_scratchpad}\",\n memoryPrompts = [],\n } = args ?? {};\n const template = [prefix, FORMAT_INSTRUCTIONS, suffix].join(\"\\n\\n\");\n const messages = [\n new SystemMessagePromptTemplate(\n new PromptTemplate({\n template,\n inputVariables,\n partialVariables: {\n tool_schemas: StructuredChatAgent.createToolSchemasString(tools),\n tool_names: tools.map((tool) => tool.name).join(\", \"),\n },\n })\n ),\n ...memoryPrompts,\n new HumanMessagePromptTemplate(\n new PromptTemplate({\n template: humanMessageTemplate,\n inputVariables,\n })\n ),\n ];\n return ChatPromptTemplate.fromMessages(messages);\n }\n\n /**\n * Creates a StructuredChatAgent from an LLM and a list of tools.\n * Validates the tools, creates a prompt, and sets up an LLM chain for the\n * agent.\n * @param llm BaseLanguageModel instance to create the agent from.\n * @param tools Array of StructuredTool instances to create the agent from.\n * @param args Optional arguments to customize the creation of the agent. Can include arguments for creating the prompt and AgentArgs.\n * @returns A new instance of StructuredChatAgent.\n */\n static fromLLMAndTools(\n llm: BaseLanguageModelInterface,\n tools: StructuredToolInterface[],\n args?: StructuredChatCreatePromptArgs & AgentArgs\n ) {\n StructuredChatAgent.validateTools(tools);\n const prompt = StructuredChatAgent.createPrompt(tools, args);\n const outputParser =\n args?.outputParser ??\n StructuredChatAgent.getDefaultOutputParser({\n llm,\n toolNames: tools.map((tool) => tool.name),\n });\n const chain = new LLMChain({\n prompt,\n llm,\n callbacks: args?.callbacks,\n });\n\n return new StructuredChatAgent({\n llmChain: chain,\n outputParser,\n allowedTools: tools.map((t) => t.name),\n });\n }\n}\n\n/**\n * Params used by the createStructuredChatAgent function.\n */\nexport type CreateStructuredChatAgentParams = {\n /** LLM to use as the agent. */\n llm: BaseLanguageModelInterface;\n /** Tools this agent has access to. */\n tools: (StructuredToolInterface | ToolDefinition)[];\n /**\n * The prompt to use. Must have input keys for\n * `tools`, `tool_names`, and `agent_scratchpad`.\n */\n prompt: BasePromptTemplate;\n /**\n * Whether to invoke the underlying model in streaming mode,\n * allowing streaming of intermediate steps. Defaults to true.\n */\n streamRunnable?: boolean;\n};\n\n/**\n * Create an agent aimed at supporting tools with multiple inputs.\n * @param params Params required to create the agent. Includes an LLM, tools, and prompt.\n * @returns A runnable sequence representing an agent. It takes as input all the same input\n * variables as the prompt passed in does. It returns as output either an\n * AgentAction or AgentFinish.\n *\n * @example\n * ```typescript\n * import { AgentExecutor, createStructuredChatAgent } from \"langchain/agents\";\n * import { pull } from \"langchain/hub\";\n * import type { ChatPromptTemplate } from \"@langchain/core/prompts\";\n * import { AIMessage, HumanMessage } from \"@langchain/core/messages\";\n *\n * import { ChatOpenAI } from \"@langchain/openai\";\n *\n * // Define the tools the agent will have access to.\n * const tools = [...];\n *\n * // Get the prompt to use - you can modify this!\n * // If you want to see the prompt in full, you can at:\n * // https://smith.langchain.com/hub/hwchase17/structured-chat-agent\n * const prompt = await pull(\n * \"hwchase17/structured-chat-agent\"\n * );\n *\n * const llm = new ChatOpenAI({\n * temperature: 0,\n * model: \"gpt-3.5-turbo-1106\",\n * });\n *\n * const agent = await createStructuredChatAgent({\n * llm,\n * tools,\n * prompt,\n * });\n *\n * const agentExecutor = new AgentExecutor({\n * agent,\n * tools,\n * });\n *\n * const result = await agentExecutor.invoke({\n * input: \"what is LangChain?\",\n * });\n *\n * // With chat history\n * const result2 = await agentExecutor.invoke({\n * input: \"what's my name?\",\n * chat_history: [\n * new HumanMessage(\"hi! my name is cob\"),\n * new AIMessage(\"Hello Cob! How can I assist you today?\"),\n * ],\n * });\n * ```\n */\nexport async function createStructuredChatAgent({\n llm,\n tools,\n prompt,\n streamRunnable,\n}: CreateStructuredChatAgentParams) {\n const missingVariables = [\"tools\", \"tool_names\", \"agent_scratchpad\"].filter(\n (v) => !prompt.inputVariables.includes(v)\n );\n if (missingVariables.length > 0) {\n throw new Error(\n `Provided prompt is missing required input variables: ${JSON.stringify(\n missingVariables\n )}`\n );\n }\n let toolNames: string[] = [];\n if (tools.every(isOpenAITool)) {\n toolNames = tools.map((tool) => tool.function.name);\n } else if (tools.every(isStructuredTool)) {\n toolNames = tools.map((tool) => tool.name);\n } else {\n throw new Error(\n \"All tools must be either OpenAI or Structured tools, not a mix.\"\n );\n }\n const partialedPrompt = await prompt.partial({\n tools: renderTextDescriptionAndArgs(tools),\n tool_names: toolNames.join(\", \"),\n });\n // TODO: Add .bind to core runnable interface.\n const llmWithStop = (llm as BaseLanguageModel).withConfig({\n stop: [\"Observation\"],\n });\n const agent = AgentRunnableSequence.fromRunnables(\n [\n RunnablePassthrough.assign({\n agent_scratchpad: (input: { steps: AgentStep[] }) =>\n formatLogToString(input.steps),\n }),\n partialedPrompt,\n llmWithStop,\n StructuredChatOutputParserWithRetries.fromLLM(llm, {\n toolNames,\n }),\n ],\n {\n name: \"StructuredChatAgent\",\n streamRunnable,\n singleAction: true,\n }\n );\n return agent;\n}\n"],"mappings":";;;;;;;;;;;;;;;;;;AAgEA,IAAa,sBAAb,MAAa,4BAA4BA,cAAAA,MAAM;CAC7C,OAAO,UAAU;AACf,SAAO;;CAGT,eAAe;EAAC;EAAa;EAAU;EAAkB;CAEzD,YAAY,OAAiC;EAC3C,MAAM,eACJ,OAAO,gBAAgB,oBAAoB,wBAAwB;AACrE,QAAM;GAAE,GAAG;GAAO;GAAc,CAAC;;CAGnC,aAAa;AACX,SAAO;;CAGT,oBAAoB;AAClB,SAAO;;CAGT,YAAY;AACV,SAAO;;CAGT,QAAkB;AAChB,SAAO,CAAC,eAAe;;;;;;;CAQzB,OAAO,cAAc,OAAkC;EACrD,MAAM,sBAAsB,MAAM,MAAM,SAAS,CAAC,KAAK,YAAY;AACnE,MAAI,qBAAqB;GACvB,MAAM,MACJ,cAAc,oBAAoB,KAAK;AAEzC,SAAM,IAAI,MAAM,IAAI;;;;;;;;;CAUxB,OAAO,uBACL,QAGA;AACA,MAAI,QAAQ,IACV,QAAOC,qBAAAA,sCAAsC,QAAQ,OAAO,KAAK,EAC/D,WAAW,OAAO,WACnB,CAAC;AAEJ,SAAO,IAAIA,qBAAAA,sCAAsC,EAC/C,WAAW,QAAQ,WACpB,CAAC;;;;;;;;;CAUJ,MAAM,oBAAoB,OAAqC;EAC7D,MAAM,kBAAkB,MAAM,MAAM,oBAAoB,MAAM;AAC9D,MAAI,gBACF,QAAO,4GAA4G;AAErH,SAAO;;;;;;;CAQT,OAAO,wBAAwB,OAAkC;AAC/D,SAAO,MACJ,KAAK,SAAS;GACb,MAAM,cAAA,GAAA,4BAAA,oBACe,KAAK,OAAO,IAAA,GAAA,kCAAA,cACd,KAAK,OAAO,GACzB,KAAK;AAEX,UAAO,GAAG,KAAK,KAAK,IAAI,KAAK,YAAY,UAAU,KAAK,UACtD,YAAY,WACb;IACD,CACD,KAAK,KAAK;;;;;;;;;;;;CAaf,OAAO,aACL,OACA,MACA;EACA,MAAM,EACJ,SAASC,eAAAA,QACT,SAASC,eAAAA,QACT,iBAAiB,CAAC,SAAS,mBAAmB,EAC9C,uBAAuB,iCACvB,gBAAgB,EAAE,KAChB,QAAQ,EAAE;EAEd,MAAM,WAAW;GACf,IAAIC,wBAAAA,4BACF,IAAIC,wBAAAA,eAAe;IACjB,UAJW;KAAC;KAAQC,eAAAA;KAAqB;KAAO,CAAC,KAAK,OAAO;IAK7D;IACA,kBAAkB;KAChB,cAAc,oBAAoB,wBAAwB,MAAM;KAChE,YAAY,MAAM,KAAK,SAAS,KAAK,KAAK,CAAC,KAAK,KAAK;KACtD;IACF,CAAC,CACH;GACD,GAAG;GACH,IAAIC,wBAAAA,2BACF,IAAIF,wBAAAA,eAAe;IACjB,UAAU;IACV;IACD,CAAC,CACH;GACF;AACD,SAAOG,wBAAAA,mBAAmB,aAAa,SAAS;;;;;;;;;;;CAYlD,OAAO,gBACL,KACA,OACA,MACA;AACA,sBAAoB,cAAc,MAAM;EACxC,MAAM,SAAS,oBAAoB,aAAa,OAAO,KAAK;EAC5D,MAAM,eACJ,MAAM,gBACN,oBAAoB,uBAAuB;GACzC;GACA,WAAW,MAAM,KAAK,SAAS,KAAK,KAAK;GAC1C,CAAC;AAOJ,SAAO,IAAI,oBAAoB;GAC7B,UAPY,IAAIC,kBAAAA,SAAS;IACzB;IACA;IACA,WAAW,MAAM;IAClB,CAAC;GAIA;GACA,cAAc,MAAM,KAAK,MAAM,EAAE,KAAK;GACvC,CAAC;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;AAgFN,eAAsB,0BAA0B,EAC9C,KACA,OACA,QACA,kBACkC;CAClC,MAAM,mBAAmB;EAAC;EAAS;EAAc;EAAmB,CAAC,QAClE,MAAM,CAAC,OAAO,eAAe,SAAS,EAAE,CAC1C;AACD,KAAI,iBAAiB,SAAS,EAC5B,OAAM,IAAI,MACR,wDAAwD,KAAK,UAC3D,iBACD,GACF;CAEH,IAAI,YAAsB,EAAE;AAC5B,KAAI,MAAM,MAAMC,qCAAAA,aAAa,CAC3B,aAAY,MAAM,KAAK,SAAS,KAAK,SAAS,KAAK;UAC1C,MAAM,MAAMC,uCAAAA,iBAAiB,CACtC,aAAY,MAAM,KAAK,SAAS,KAAK,KAAK;KAE1C,OAAM,IAAI,MACR,kEACD;CAEH,MAAM,kBAAkB,MAAM,OAAO,QAAQ;EAC3C,OAAOC,qBAAAA,6BAA6B,MAAM;EAC1C,YAAY,UAAU,KAAK,KAAK;EACjC,CAAC;CAEF,MAAM,cAAe,IAA0B,WAAW,EACxD,MAAM,CAAC,cAAc,EACtB,CAAC;AAmBF,QAlBcC,cAAAA,sBAAsB,cAClC;EACEC,0BAAAA,oBAAoB,OAAO,EACzB,mBAAmB,UACjBC,qCAAAA,kBAAkB,MAAM,MAAM,EACjC,CAAC;EACF;EACA;EACAd,qBAAAA,sCAAsC,QAAQ,KAAK,EACjD,WACD,CAAC;EACH,EACD;EACE,MAAM;EACN;EACA,cAAc;EACf,CACF"}