feat: jsonagent

src/backend/langflow/custom/customs.py

@@ -4,6 +4,7 @@ from langflow.template import nodes
 CUSTOM_NODES = {
     "prompts": {**nodes.ZeroShotPromptNode().to_dict()},
     "tools": {**nodes.PythonFunctionNode().to_dict(), **nodes.ToolNode().to_dict()},
+    "agents": {**nodes.JsonAgentNode().to_dict()},
 }
 
 

src/backend/langflow/interface/custom_lists.py

@@ -59,6 +59,7 @@ toolkit_type_to_cls_dict: dict[str, Any] = {
     if not toolkit_name.islower()
 }
 
+
 wrapper_type_to_cls_dict: dict[str, Any] = {
     wrapper.__name__: wrapper for wrapper in [requests.RequestsWrapper]
 }

src/backend/langflow/interface/custom_types.py

@@ -1,6 +1,12 @@
 from typing import Callable, Optional
+from langchain import LLMChain, PromptTemplate
+from langchain.agents import AgentExecutor, ZeroShotAgent
 from langflow.utils import validate
 from pydantic import BaseModel, validator
+from langchain.agents.agent_toolkits.json.prompt import JSON_PREFIX, JSON_SUFFIX
+from langchain.agents.mrkl.prompt import FORMAT_INSTRUCTIONS
+from langchain.agents.agent_toolkits.json.toolkit import JsonToolkit
+from langchain.schema import BaseLanguageModel
 
 
 class Function(BaseModel):
@@ -33,3 +39,31 @@ class PythonFunction(Function):
     """Python function"""
 
     code: str
+
+
+class JsonAgent(BaseModel):
+    """Json agent"""
+
+    toolkit: JsonToolkit
+    llm: BaseLanguageModel
+
+    def __init__(self, toolkit: JsonToolkit, llm: BaseLanguageModel):
+        super().__init__(toolkit=toolkit, llm=llm)
+        self.toolkit = toolkit
+        tools = self.toolkit.get_tools()
+        tool_names = [tool.name for tool in tools]
+        prompt = ZeroShotAgent.create_prompt(
+            tools,
+            prefix=JSON_PREFIX,
+            suffix=JSON_SUFFIX,
+            format_instructions=FORMAT_INSTRUCTIONS,
+            input_variables=None,
+        )
+        llm_chain = LLMChain(
+            llm=llm,
+            prompt=prompt,
+        )
+        agent = ZeroShotAgent(llm_chain=llm_chain, allowed_tools=tool_names)
+        return AgentExecutor.from_agent_and_tools(
+            agent=agent, tools=tools, verbose=True
+        )

src/backend/langflow/interface/listing.py

@@ -10,7 +10,7 @@ from langflow.settings import settings
 from langflow.utils import util
 from langchain.agents.load_tools import get_all_tool_names
 from langchain.agents import Tool
-from langflow.interface.custom_types import PythonFunction
+from langflow.interface.custom_types import JsonAgent, PythonFunction
 from langchain.tools.json.tool import JsonSpec
 
 OTHER_TOOLS = {"JsonSpec": JsonSpec}
@@ -50,7 +50,7 @@ def list_agents():
         agent.__name__
         for agent in agents.loading.AGENT_TO_CLASS.values()
         if agent.__name__ in settings.agents or settings.dev
-    ]
+    ] + [JsonAgent.__name__]
 
 
 def list_toolkis():

src/backend/langflow/interface/signature.py

@@ -40,7 +40,7 @@ def get_toolkit_signature(name: str):
     """Get the signature of a toolkit."""
     try:
         if name.islower():
-            pass
+            ...
             # return util.build_template_from_function(
             #     name, toolkit_type_to_loader_dict, add_function=True
             # )
@@ -77,6 +77,8 @@ def get_chain_signature(name: str):
 def get_agent_signature(name: str):
     """Get the signature of an agent."""
     try:
+        if name in customs.get_custom_nodes("agents").keys():
+            return customs.get_custom_nodes("agents")[name]
         return util.build_template_from_class(
             name, agents.loading.AGENT_TO_CLASS, add_function=True
         )

src/backend/langflow/template/nodes.py

@@ -112,3 +112,35 @@ class ToolNode(FrontendNode):
 
     def to_dict(self):
         return super().to_dict()
+
+
+class JsonAgentNode(FrontendNode):
+    name: str = "JsonAgent"
+    template: Template = Template(
+        type_name="json_agent",
+        fields=[
+            Field(
+                field_type="BaseToolkit",
+                required=True,
+                placeholder="",
+                is_list=False,
+                show=True,
+                value="",
+                name="toolkit",
+            ),
+            Field(
+                field_type="BaseLanguageModel",
+                required=True,
+                placeholder="",
+                is_list=False,
+                show=True,
+                value="",
+                name="LLM",
+            ),
+        ],
+    )
+    description: str = """Construct a json agent from an LLM and tools."""
+    base_classes: list[str] = ["BaseAgent"]
+
+    def to_dict(self):
+        return super().to_dict()

src/backend/langflow/utils/util.py

@@ -406,6 +406,7 @@ def format_dict(d, name: Optional[str] = None):
                 "examples",
                 "temperature",
                 "model_name",
+                "headers",
             ]
             or "api_key" in key
         )
@@ -427,7 +428,7 @@ def format_dict(d, name: Optional[str] = None):
 
         # Replace dict type with str
         if "dict" in value["type"].lower():
-            value["type"] = "str"
+            value["type"] = "code"
 
         value["file"] = key in ["dict_"]
 
@@ -436,6 +437,11 @@ def format_dict(d, name: Optional[str] = None):
             value["value"] = value["default"]
             value.pop("default")
 
+        if key == "headers":
+            value[
+                "value"
+            ] = """{'Authorization':
+            'Bearer <token>'}"""
         # Add options to openai
         if name == "OpenAI" and key == "model_name":
             value["options"] = constants.OPENAI_MODELS