Add support for HTTP PUT in the open api agent prompt (#10763)

**Description:** This PR adds HTTP PUT support for the langchain openapi
agent toolkit by leveraging existing structure and HTTP put request
wrapper. The PUT method is almost identical to HTTP POST but should be
idempotent and therefore tighter than POST which is not idempotent. Some
APIs may consider to use PUT instead of POST which is unfortunately not
supported with the current toolkit yet.

libs/langchain/langchain/agents/agent_toolkits/openapi/planner.py

@@ -19,10 +19,12 @@ from langchain.agents.agent_toolkits.openapi.planner_prompt import (
     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.agents.agent_toolkits.openapi.spec import ReducedOpenAPISpec
 from langchain.agents.mrkl.base import ZeroShotAgent
@@ -151,6 +153,35 @@ class RequestsPatchToolWithParsing(BaseRequestsTool, BaseTool):
         raise NotImplementedError()
 
 
+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: Optional[int] = MAX_RESPONSE_LENGTH
+    """Maximum length of the response to be returned."""
+    llm_chain: LLMChain = Field(
+        default_factory=_get_default_llm_chain_factory(PARSING_PUT_PROMPT)
+    )
+    """LLMChain used to extract the response."""
+
+    def _run(self, text: str) -> str:
+        try:
+            data = json.loads(text)
+        except json.JSONDecodeError as e:
+            raise e
+        response = 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()
+
+
 class RequestsDeleteToolWithParsing(BaseRequestsTool, BaseTool):
     """A tool that sends a DELETE request and parses the response."""
 

libs/langchain/langchain/agents/agent_toolkits/openapi/planner_prompt.py

@@ -24,6 +24,7 @@ GET /user to get information about the current user
 GET /products/search search across products
 POST /users/{{id}}/cart to add products to a user's cart
 PATCH /users/{{id}}/cart to update a user's cart
+PUT /users/{{id}}/coupon to apply idempotent coupon to a user's cart
 DELETE /users/{{id}}/cart to delete a user's cart
 
 User query: tell me a joke
@@ -39,6 +40,10 @@ Plan: 1. GET /products with a query param to search for lamps
 2. GET /user to find the user's id
 3. PATCH /users/{{id}}/cart to add a lamp to the user's cart
 
+User query: I want to add a coupon to my cart
+Plan: 1. GET /user to find the user's id
+2. PUT /users/{{id}}/coupon to apply the coupon
+
 User query: I want to delete my cart
 Plan: 1. GET /user to find the user's id
 2. DELETE required. Did user specify DELETE or previously authorize? Yes, proceed.
@@ -195,6 +200,23 @@ Output:""",
     input_variables=["response", "instructions"],
 )
 
+REQUESTS_PUT_TOOL_DESCRIPTION = """Use this when you want to PUT to a website.
+Input to the tool should be a json string with 3 keys: "url", "data", and "output_instructions".
+The value of "url" should be a string.
+The value of "data" should be a dictionary of key-value pairs you want to PUT to the url.
+The value of "output_instructions" should be instructions on what information to extract from the response, for example the id(s) for a resource(s) that the PUT request creates.
+Always use double quotes for strings in the json string."""
+
+PARSING_PUT_PROMPT = PromptTemplate(
+    template="""Here is an API response:\n\n{response}\n\n====
+Your task is to extract some information according to these instructions: {instructions}
+When working with API objects, you should usually use ids over names. Do not return any ids or names that are not in the response.
+If the response indicates an error, you should instead output a summary of the error.
+
+Output:""",
+    input_variables=["response", "instructions"],
+)
+
 REQUESTS_DELETE_TOOL_DESCRIPTION = """ONLY USE THIS TOOL WHEN THE USER HAS SPECIFICALLY REQUESTED TO DELETE CONTENT FROM A WEBSITE.
 Input to the tool should be a json string with 2 keys: "url", and "output_instructions".
 The value of "url" should be a string.

libs/langchain/langchain/agents/agent_toolkits/openapi/spec.py

@@ -31,12 +31,12 @@ def reduce_openapi_spec(spec: dict, dereference: bool = True) -> ReducedOpenAPIS
     I was hoping https://openapi.tools/ would have some useful bits
     to this end, but doesn't seem so.
     """
-    # 1. Consider only get, post, patch, delete endpoints.
+    # 1. Consider only get, post, patch, put, delete endpoints.
     endpoints = [
         (f"{operation_name.upper()} {route}", docs.get("description"), docs)
         for route, operation in spec["paths"].items()
         for operation_name, docs in operation.items()
-        if operation_name in ["get", "post", "patch", "delete"]
+        if operation_name in ["get", "post", "patch", "put", "delete"]
     ]
 
     # 2. Replace any refs so that complete docs are retrieved.