✨ feat(agents/base.py): add support for creating frontend nodes for agents

🔧 fix(agents/base.py): import missing AgentFrontendNode class from langflow.template.frontend_node.agents
🔧 fix(initialize/loading.py): pass node_type to instantiate_agent function to handle creation of frontend nodes for agents
🔧 fix(template/frontend_node/agents.py): add format_field method to AgentFrontendNode class to customize field behavior
The missing import statement for the AgentFrontendNode class from langflow.template.frontend_node.agents has been added to the base.py file. Support for creating frontend nodes for agents has been added to the AgentCreator class in the base.py file. The instantiate_agent function in the loading.py file now receives the node_type parameter to handle the creation of frontend nodes for agents. The AgentFrontendNode class in the agents.py file now includes a format_field method to customize the behavior of certain fields.

src/backend/langflow/interface/agents/base.py

@@ -6,13 +6,20 @@ from langflow.custom.customs import get_custom_nodes
 from langflow.interface.agents.custom import CUSTOM_AGENTS
 from langflow.interface.base import LangChainTypeCreator
 from langflow.settings import settings
+from langflow.template.frontend_node.agents import AgentFrontendNode
 from langflow.utils.logger import logger
-from langflow.utils.util import build_template_from_class
+from langflow.utils.util import build_template_from_class, build_template_from_method
 
 
 class AgentCreator(LangChainTypeCreator):
     type_name: str = "agents"
 
+    from_method_nodes = {"ZeroShotAgent": "from_llm_and_tools"}
+
+    @property
+    def frontend_node_class(self) -> type[AgentFrontendNode]:
+        return AgentFrontendNode
+
     @property
     def type_to_loader_dict(self) -> Dict:
         if self.type_dict is None:
@@ -27,6 +34,13 @@ class AgentCreator(LangChainTypeCreator):
         try:
             if name in get_custom_nodes(self.type_name).keys():
                 return get_custom_nodes(self.type_name)[name]
+            elif name in self.from_method_nodes:
+                return build_template_from_method(
+                    name,
+                    type_to_cls_dict=self.type_to_loader_dict,
+                    add_function=True,
+                    method_name=self.from_method_nodes[name],
+                )
             return build_template_from_class(
                 name, self.type_to_loader_dict, add_function=True
             )

src/backend/langflow/interface/initialize/loading.py

@@ -15,6 +15,7 @@ from pydantic import ValidationError
 
 from langflow.interface.custom_lists import CUSTOM_NODES
 from langflow.interface.importing.utils import get_function, import_by_type
+from langflow.interface.agents.base import agent_creator
 from langflow.interface.toolkits.base import toolkits_creator
 from langflow.interface.chains.base import chain_creator
 from langflow.interface.output_parsers.base import output_parser_creator
@@ -61,7 +62,7 @@ def convert_kwargs(params):
 
 def instantiate_based_on_type(class_object, base_type, node_type, params):
     if base_type == "agents":
-        return instantiate_agent(class_object, params)
+        return instantiate_agent(node_type, class_object, params)
     elif base_type == "prompts":
         return instantiate_prompt(node_type, class_object, params)
     elif base_type == "tools":
@@ -159,7 +160,16 @@ def instantiate_chains(node_type, class_object: Type[Chain], params: Dict):
     return class_object(**params)
 
 
-def instantiate_agent(class_object: Type[agent_module.Agent], params: Dict):
+def instantiate_agent(node_type, class_object: Type[agent_module.Agent], params: Dict):
+    if node_type in agent_creator.from_method_nodes:
+        method = agent_creator.from_method_nodes[node_type]
+        if class_method := getattr(class_object, method, None):
+            agent = class_method(**params)
+            tools = params.get("tools", [])
+            return AgentExecutor.from_agent_and_tools(
+                agent=agent,
+                tools=tools,
+            )
     return load_agent_executor(class_object, params)
 
 

src/backend/langflow/template/frontend_node/agents.py

@@ -13,6 +13,17 @@ NON_CHAT_AGENTS = {
 }
 
 
+class AgentFrontendNode(FrontendNode):
+    @staticmethod
+    def format_field(field: TemplateField, name: str | None = None) -> None:
+        if field.name in ["suffix", "prefix"]:
+            field.show = True
+        if field.name == "Tools" and name == "ZeroShotAgent":
+            # field.
+            field.type_name = "BaseTool"
+            field.is_list = True
+
+
 class SQLAgentNode(FrontendNode):
     name: str = "SQLAgent"
     template: Template = Template(