feat: add MCP support (#20716)

Co-authored-by: QuantumGhost <obelisk.reg+git@gmail.com>

api/core/workflow/nodes/agent/agent_node.py

@@ -3,11 +3,13 @@ import uuid
 from collections.abc import Generator, Mapping, Sequence
 from typing import Any, Optional, cast
 
+from packaging.version import Version
 from sqlalchemy import select
 from sqlalchemy.orm import Session
 
 from core.agent.entities import AgentToolEntity
 from core.agent.plugin_entities import AgentStrategyParameter
+from core.agent.strategy.plugin import PluginAgentStrategy
 from core.memory.token_buffer_memory import TokenBufferMemory
 from core.model_manager import ModelInstance, ModelManager
 from core.model_runtime.entities.model_entities import AIModelEntity, ModelType
@@ -73,12 +75,14 @@ class AgentNode(ToolNode):
             agent_parameters=agent_parameters,
             variable_pool=self.graph_runtime_state.variable_pool,
             node_data=node_data,
+            strategy=strategy,
         )
         parameters_for_log = self._generate_agent_parameters(
             agent_parameters=agent_parameters,
             variable_pool=self.graph_runtime_state.variable_pool,
             node_data=node_data,
             for_log=True,
+            strategy=strategy,
         )
 
         # get conversation id
@@ -155,6 +159,7 @@ class AgentNode(ToolNode):
         variable_pool: VariablePool,
         node_data: AgentNodeData,
         for_log: bool = False,
+        strategy: PluginAgentStrategy,
     ) -> dict[str, Any]:
         """
         Generate parameters based on the given tool parameters, variable pool, and node data.
@@ -207,7 +212,7 @@ class AgentNode(ToolNode):
             if parameter.type == "array[tools]":
                 value = cast(list[dict[str, Any]], value)
                 value = [tool for tool in value if tool.get("enabled", False)]
-
+                value = self._filter_mcp_type_tool(strategy, value)
                 for tool in value:
                     if "schemas" in tool:
                         tool.pop("schemas")
@@ -244,9 +249,9 @@ class AgentNode(ToolNode):
                         )
 
                         extra = tool.get("extra", {})
-
+                        runtime_variable_pool = variable_pool if self.node_data.version != "1" else None
                         tool_runtime = ToolManager.get_agent_tool_runtime(
-                            self.tenant_id, self.app_id, entity, self.invoke_from
+                            self.tenant_id, self.app_id, entity, self.invoke_from, runtime_variable_pool
                         )
                         if tool_runtime.entity.description:
                             tool_runtime.entity.description.llm = (
@@ -398,3 +403,16 @@ class AgentNode(ToolNode):
                 except ValueError:
                     model_schema.features.remove(feature)
         return model_schema
+
+    def _filter_mcp_type_tool(self, strategy: PluginAgentStrategy, tools: list[dict[str, Any]]) -> list[dict[str, Any]]:
+        """
+        Filter MCP type tool
+        :param strategy: plugin agent strategy
+        :param tool: tool
+        :return: filtered tool dict
+        """
+        meta_version = strategy.meta_version
+        if meta_version and Version(meta_version) > Version("0.0.1"):
+            return tools
+        else:
+            return [tool for tool in tools if tool.get("type") != ToolProviderType.MCP.value]

api/core/workflow/nodes/node_mapping.py

@@ -73,6 +73,7 @@ NODE_TYPE_CLASSES_MAPPING: Mapping[NodeType, Mapping[str, type[BaseNode]]] = {
     },
     NodeType.TOOL: {
         LATEST_VERSION: ToolNode,
+        "2": ToolNode,
         "1": ToolNode,
     },
     NodeType.VARIABLE_AGGREGATOR: {
@@ -122,6 +123,7 @@ NODE_TYPE_CLASSES_MAPPING: Mapping[NodeType, Mapping[str, type[BaseNode]]] = {
     },
     NodeType.AGENT: {
         LATEST_VERSION: AgentNode,
+        "2": AgentNode,
         "1": AgentNode,
     },
 }

api/core/workflow/nodes/tool/entities.py

@@ -41,6 +41,10 @@ class ToolNodeData(BaseNodeData, ToolEntity):
         def check_type(cls, value, validation_info: ValidationInfo):
             typ = value
             value = validation_info.data.get("value")
+
+            if value is None:
+                return typ
+
             if typ == "mixed" and not isinstance(value, str):
                 raise ValueError("value must be a string")
             elif typ == "variable":
@@ -54,3 +58,22 @@ class ToolNodeData(BaseNodeData, ToolEntity):
             return typ
 
     tool_parameters: dict[str, ToolInput]
+
+    @field_validator("tool_parameters", mode="before")
+    @classmethod
+    def filter_none_tool_inputs(cls, value):
+        if not isinstance(value, dict):
+            return value
+
+        return {
+            key: tool_input
+            for key, tool_input in value.items()
+            if tool_input is not None and cls._has_valid_value(tool_input)
+        }
+
+    @staticmethod
+    def _has_valid_value(tool_input):
+        """Check if the value is valid"""
+        if isinstance(tool_input, dict):
+            return tool_input.get("value") is not None
+        return getattr(tool_input, "value", None) is not None

api/core/workflow/nodes/tool/tool_node.py

@@ -67,8 +67,9 @@ class ToolNode(BaseNode[ToolNodeData]):
         try:
             from core.tools.tool_manager import ToolManager
 
+            variable_pool = self.graph_runtime_state.variable_pool if self.node_data.version != "1" else None
             tool_runtime = ToolManager.get_workflow_tool_runtime(
-                self.tenant_id, self.app_id, self.node_id, self.node_data, self.invoke_from
+                self.tenant_id, self.app_id, self.node_id, self.node_data, self.invoke_from, variable_pool
             )
         except ToolNodeError as e:
             yield RunCompletedEvent(
@@ -95,7 +96,6 @@ class ToolNode(BaseNode[ToolNodeData]):
             node_data=self.node_data,
             for_log=True,
         )
-
         # get conversation id
         conversation_id = self.graph_runtime_state.variable_pool.get(["sys", SystemVariableKey.CONVERSATION_ID])