Source code for langchain_community.agent_toolkits.openapi.planner

"""Agent that interacts with OpenAPI APIs via a hierarchical planning approach."""
import json
import re
from functools import partial
from typing import Any, Callable, Dict, List, Optional, cast

import yaml
from langchain_core.callbacks import BaseCallbackManager
from langchain_core.language_models import BaseLanguageModel
from langchain_core.prompts import BasePromptTemplate, PromptTemplate
from langchain_core.pydantic_v1 import Field
from langchain_core.tools import BaseTool, Tool

from langchain_community.agent_toolkits.openapi.planner_prompt import (
    API_CONTROLLER_PROMPT,
    API_CONTROLLER_TOOL_DESCRIPTION,
    API_CONTROLLER_TOOL_NAME,
    API_ORCHESTRATOR_PROMPT,
    API_PLANNER_PROMPT,
    API_PLANNER_TOOL_DESCRIPTION,
    API_PLANNER_TOOL_NAME,
    PARSING_DELETE_PROMPT,
    PARSING_GET_PROMPT,
    PARSING_PATCH_PROMPT,
    PARSING_POST_PROMPT,
    PARSING_PUT_PROMPT,
    REQUESTS_DELETE_TOOL_DESCRIPTION,
    REQUESTS_GET_TOOL_DESCRIPTION,
    REQUESTS_PATCH_TOOL_DESCRIPTION,
    REQUESTS_POST_TOOL_DESCRIPTION,
    REQUESTS_PUT_TOOL_DESCRIPTION,
)
from langchain_community.agent_toolkits.openapi.spec import ReducedOpenAPISpec
from langchain_community.llms import OpenAI
from langchain_community.tools.requests.tool import BaseRequestsTool
from langchain_community.utilities.requests import RequestsWrapper

#
# Requests tools with LLM-instructed extraction of truncated responses.
#
# Of course, truncating so bluntly may lose a lot of valuable
# information in the response.
# However, the goal for now is to have only a single inference step.
MAX_RESPONSE_LENGTH = 5000
"""Maximum length of the response to be returned."""


def _get_default_llm_chain(prompt: BasePromptTemplate) -> Any:
    from langchain.chains.llm import LLMChain

    return LLMChain(
        llm=OpenAI(),
        prompt=prompt,
    )


def _get_default_llm_chain_factory(
    prompt: BasePromptTemplate,
) -> Callable[[], Any]:
    """Returns a default LLMChain factory."""
    return partial(_get_default_llm_chain, prompt)


[docs]class RequestsGetToolWithParsing(BaseRequestsTool, BaseTool): """Requests GET tool with LLM-instructed extraction of truncated responses.""" name: str = "requests_get" """Tool name.""" description = REQUESTS_GET_TOOL_DESCRIPTION """Tool description.""" response_length: int = MAX_RESPONSE_LENGTH """Maximum length of the response to be returned.""" llm_chain: Any = Field( default_factory=_get_default_llm_chain_factory(PARSING_GET_PROMPT) ) """LLMChain used to extract the response.""" def _run(self, text: str) -> str: from langchain.output_parsers.json import parse_json_markdown try: data = parse_json_markdown(text) except json.JSONDecodeError as e: raise e data_params = data.get("params") response: str = cast( str, self.requests_wrapper.get(data["url"], params=data_params) ) response = response[: self.response_length] return self.llm_chain.predict( response=response, instructions=data["output_instructions"] ).strip() async def _arun(self, text: str) -> str: raise NotImplementedError()
[docs]class RequestsPostToolWithParsing(BaseRequestsTool, BaseTool): """Requests POST tool with LLM-instructed extraction of truncated responses.""" name: str = "requests_post" """Tool name.""" description = REQUESTS_POST_TOOL_DESCRIPTION """Tool description.""" response_length: int = MAX_RESPONSE_LENGTH """Maximum length of the response to be returned.""" llm_chain: Any = Field( default_factory=_get_default_llm_chain_factory(PARSING_POST_PROMPT) ) """LLMChain used to extract the response.""" def _run(self, text: str) -> str: from langchain.output_parsers.json import parse_json_markdown try: data = parse_json_markdown(text) except json.JSONDecodeError as e: raise e response: str = cast(str, self.requests_wrapper.post(data["url"], data["data"])) response = response[: self.response_length] return self.llm_chain.predict( response=response, instructions=data["output_instructions"] ).strip() async def _arun(self, text: str) -> str: raise NotImplementedError()
[docs]class RequestsPatchToolWithParsing(BaseRequestsTool, BaseTool): """Requests PATCH tool with LLM-instructed extraction of truncated responses.""" name: str = "requests_patch" """Tool name.""" description = REQUESTS_PATCH_TOOL_DESCRIPTION """Tool description.""" response_length: int = MAX_RESPONSE_LENGTH """Maximum length of the response to be returned.""" llm_chain: Any = Field( default_factory=_get_default_llm_chain_factory(PARSING_PATCH_PROMPT) ) """LLMChain used to extract the response.""" def _run(self, text: str) -> str: from langchain.output_parsers.json import parse_json_markdown try: data = parse_json_markdown(text) except json.JSONDecodeError as e: raise e response: str = cast( str, self.requests_wrapper.patch(data["url"], data["data"]) ) response = response[: self.response_length] return self.llm_chain.predict( response=response, instructions=data["output_instructions"] ).strip() async def _arun(self, text: str) -> str: raise NotImplementedError()
[docs]class RequestsPutToolWithParsing(BaseRequestsTool, BaseTool): """Requests PUT tool with LLM-instructed extraction of truncated responses.""" name: str = "requests_put" """Tool name.""" description = REQUESTS_PUT_TOOL_DESCRIPTION """Tool description.""" response_length: int = MAX_RESPONSE_LENGTH """Maximum length of the response to be returned.""" llm_chain: Any = Field( default_factory=_get_default_llm_chain_factory(PARSING_PUT_PROMPT) ) """LLMChain used to extract the response.""" def _run(self, text: str) -> str: from langchain.output_parsers.json import parse_json_markdown try: data = parse_json_markdown(text) except json.JSONDecodeError as e: raise e response: str = cast(str, self.requests_wrapper.put(data["url"], data["data"])) response = response[: self.response_length] return self.llm_chain.predict( response=response, instructions=data["output_instructions"] ).strip() async def _arun(self, text: str) -> str: raise NotImplementedError()
[docs]class RequestsDeleteToolWithParsing(BaseRequestsTool, BaseTool): """Tool that sends a DELETE request and parses the response.""" name: str = "requests_delete" """The name of the tool.""" description = REQUESTS_DELETE_TOOL_DESCRIPTION """The description of the tool.""" response_length: Optional[int] = MAX_RESPONSE_LENGTH """The maximum length of the response.""" llm_chain: Any = Field( default_factory=_get_default_llm_chain_factory(PARSING_DELETE_PROMPT) ) """The LLM chain used to parse the response.""" def _run(self, text: str) -> str: from langchain.output_parsers.json import parse_json_markdown try: data = parse_json_markdown(text) except json.JSONDecodeError as e: raise e response: str = cast(str, self.requests_wrapper.delete(data["url"])) response = response[: self.response_length] return self.llm_chain.predict( response=response, instructions=data["output_instructions"] ).strip() async def _arun(self, text: str) -> str: raise NotImplementedError()
# # Orchestrator, planner, controller. # def _create_api_planner_tool( api_spec: ReducedOpenAPISpec, llm: BaseLanguageModel ) -> Tool: from langchain.chains.llm import LLMChain endpoint_descriptions = [ f"{name} {description}" for name, description, _ in api_spec.endpoints ] prompt = PromptTemplate( template=API_PLANNER_PROMPT, input_variables=["query"], partial_variables={"endpoints": "- " + "- ".join(endpoint_descriptions)}, ) chain = LLMChain(llm=llm, prompt=prompt) tool = Tool( name=API_PLANNER_TOOL_NAME, description=API_PLANNER_TOOL_DESCRIPTION, func=chain.run, ) return tool def _create_api_controller_agent( api_url: str, api_docs: str, requests_wrapper: RequestsWrapper, llm: BaseLanguageModel, ) -> Any: from langchain.agents.agent import AgentExecutor from langchain.agents.mrkl.base import ZeroShotAgent from langchain.chains.llm import LLMChain get_llm_chain = LLMChain(llm=llm, prompt=PARSING_GET_PROMPT) post_llm_chain = LLMChain(llm=llm, prompt=PARSING_POST_PROMPT) tools: List[BaseTool] = [ RequestsGetToolWithParsing( requests_wrapper=requests_wrapper, llm_chain=get_llm_chain ), RequestsPostToolWithParsing( requests_wrapper=requests_wrapper, llm_chain=post_llm_chain ), ] prompt = PromptTemplate( template=API_CONTROLLER_PROMPT, input_variables=["input", "agent_scratchpad"], partial_variables={ "api_url": api_url, "api_docs": api_docs, "tool_names": ", ".join([tool.name for tool in tools]), "tool_descriptions": "\n".join( [f"{tool.name}: {tool.description}" for tool in tools] ), }, ) agent = ZeroShotAgent( llm_chain=LLMChain(llm=llm, prompt=prompt), allowed_tools=[tool.name for tool in tools], ) return AgentExecutor.from_agent_and_tools(agent=agent, tools=tools, verbose=True) def _create_api_controller_tool( api_spec: ReducedOpenAPISpec, requests_wrapper: RequestsWrapper, llm: BaseLanguageModel, ) -> Tool: """Expose controller as a tool. The tool is invoked with a plan from the planner, and dynamically creates a controller agent with relevant documentation only to constrain the context. """ base_url = api_spec.servers[0]["url"] # TODO: do better. def _create_and_run_api_controller_agent(plan_str: str) -> str: pattern = r"\b(GET|POST|PATCH|DELETE)\s+(/\S+)*" matches = re.findall(pattern, plan_str) endpoint_names = [ "{method} {route}".format(method=method, route=route.split("?")[0]) for method, route in matches ] docs_str = "" for endpoint_name in endpoint_names: found_match = False for name, _, docs in api_spec.endpoints: regex_name = re.compile(re.sub("\{.*?\}", ".*", name)) if regex_name.match(endpoint_name): found_match = True docs_str += f"== Docs for {endpoint_name} == \n{yaml.dump(docs)}\n" if not found_match: raise ValueError(f"{endpoint_name} endpoint does not exist.") agent = _create_api_controller_agent(base_url, docs_str, requests_wrapper, llm) return agent.run(plan_str) return Tool( name=API_CONTROLLER_TOOL_NAME, func=_create_and_run_api_controller_agent, description=API_CONTROLLER_TOOL_DESCRIPTION, )
[docs]def create_openapi_agent( api_spec: ReducedOpenAPISpec, requests_wrapper: RequestsWrapper, llm: BaseLanguageModel, shared_memory: Optional[Any] = None, callback_manager: Optional[BaseCallbackManager] = None, verbose: bool = True, agent_executor_kwargs: Optional[Dict[str, Any]] = None, **kwargs: Any, ) -> Any: """Instantiate OpenAI API planner and controller for a given spec. Inject credentials via requests_wrapper. We use a top-level "orchestrator" agent to invoke the planner and controller, rather than a top-level planner that invokes a controller with its plan. This is to keep the planner simple. """ from langchain.agents.agent import AgentExecutor from langchain.agents.mrkl.base import ZeroShotAgent from langchain.chains.llm import LLMChain tools = [ _create_api_planner_tool(api_spec, llm), _create_api_controller_tool(api_spec, requests_wrapper, llm), ] prompt = PromptTemplate( template=API_ORCHESTRATOR_PROMPT, input_variables=["input", "agent_scratchpad"], partial_variables={ "tool_names": ", ".join([tool.name for tool in tools]), "tool_descriptions": "\n".join( [f"{tool.name}: {tool.description}" for tool in tools] ), }, ) agent = ZeroShotAgent( llm_chain=LLMChain(llm=llm, prompt=prompt, memory=shared_memory), allowed_tools=[tool.name for tool in tools], **kwargs, ) return AgentExecutor.from_agent_and_tools( agent=agent, tools=tools, callback_manager=callback_manager, verbose=verbose, **(agent_executor_kwargs or {}), )