feat(agent-runner): support host tool lookup

src/langbot/pkg/provider/tools/errors.py

@@ -0,0 +1,6 @@
+class ToolNotFoundError(ValueError):
+    """Raised when a requested tool cannot be found in any active loader."""
+
+    def __init__(self, name: str):
+        self.name = name
+        super().__init__(f'Tool not found: {name}')

src/langbot/pkg/provider/tools/loader.py

@@ -4,12 +4,15 @@ import abc
 import typing
 from typing import TYPE_CHECKING
 
+from langbot_plugin.api.definition.components.manifest import ComponentManifest
 from langbot_plugin.api.entities.events import pipeline_query
 import langbot_plugin.api.entities.builtin.resource.tool as resource_tool
 
 if TYPE_CHECKING:
     from ...core import app
 
+ToolLookupResult = resource_tool.LLMTool | ComponentManifest
+
 
 preregistered_loaders: list[typing.Type[ToolLoader]] = []
 
@@ -43,6 +46,13 @@ class ToolLoader(abc.ABC):
         """获取所有工具"""
         pass
 
+    async def get_tool(self, name: str) -> ToolLookupResult | None:
+        """Get one tool by name."""
+        for tool in await self.get_tools():
+            if tool.name == name:
+                return tool
+        return None
+
     @abc.abstractmethod
     async def has_tool(self, name: str) -> bool:
         """检查工具是否存在"""

src/langbot/pkg/provider/tools/loaders/mcp.py

@@ -567,6 +567,13 @@ class MCPLoader(loader.ToolLoader):
                     return True
         return False
 
+    async def get_tool(self, name: str) -> resource_tool.LLMTool | None:
+        for session in self.sessions.values():
+            for function in session.get_tools():
+                if function.name == name:
+                    return function
+        return None
+
     async def invoke_tool(self, name: str, parameters: dict, query: pipeline_query.Query) -> typing.Any:
         """执行工具调用"""
         for session in self.sessions.values():

src/langbot/pkg/provider/tools/loaders/native.py

@@ -7,6 +7,7 @@ import langbot_plugin.api.entities.builtin.resource.tool as resource_tool
 from langbot_plugin.api.entities.events import pipeline_query
 
 from .. import loader
+from ..errors import ToolNotFoundError
 from . import skill as skill_loader
 
 EXEC_TOOL_NAME = 'exec'
@@ -90,7 +91,7 @@ class NativeToolLoader(loader.ToolLoader):
             return await self._invoke_glob(parameters, query)
         if name == GREP_TOOL_NAME:
             return await self._invoke_grep(parameters, query)
-        raise ValueError(f'未找到工具: {name}')
+        raise ToolNotFoundError(name)
 
     async def shutdown(self):
         pass

src/langbot/pkg/provider/tools/loaders/plugin.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 import typing
 import traceback
 
+from langbot_plugin.api.definition.components.manifest import ComponentManifest
 from langbot_plugin.api.entities.events import pipeline_query
 
 from .. import loader
@@ -39,7 +40,7 @@ class PluginToolLoader(loader.ToolLoader):
                 return True
         return False
 
-    async def _get_tool(self, name: str) -> resource_tool.LLMTool:
+    async def get_tool(self, name: str) -> ComponentManifest | None:
         for tool in await self.ap.plugin_connector.list_tools():
             if tool.metadata.name == name:
                 return tool

src/langbot/pkg/provider/tools/toolmgr.py

@@ -6,6 +6,9 @@ from typing import TYPE_CHECKING
 import langbot_plugin.api.entities.builtin.resource.tool as resource_tool
 from langbot_plugin.api.entities.events import pipeline_query
 
+from . import loader as tool_loader
+from .errors import ToolNotFoundError
+
 if TYPE_CHECKING:
     from ...core import app
     from langbot.pkg.provider.tools.loaders import (
@@ -67,6 +70,20 @@ class ToolManager:
 
         return all_functions
 
+    async def get_tool_by_name(self, name: str) -> tool_loader.ToolLookupResult | None:
+        """Get tool by name from any active loader."""
+        for active_loader in (
+            self.native_tool_loader,
+            self.plugin_tool_loader,
+            self.mcp_tool_loader,
+            self.skill_tool_loader,
+        ):
+            tool = await active_loader.get_tool(name)
+            if tool:
+                return tool
+
+        return None
+
     async def generate_tools_for_openai(self, use_funcs: list[resource_tool.LLMTool]) -> list:
         tools = []
 
@@ -98,7 +115,7 @@ class ToolManager:
         if await self.skill_tool_loader.has_tool(name):
             telemetry_features.increment(query, 'tool_calls', 'skill')
             return await self.skill_tool_loader.invoke_tool(name, parameters, query)
-        raise ValueError(f'未找到工具: {name}')
+        raise ToolNotFoundError(name)
 
     async def shutdown(self):
         await self.native_tool_loader.shutdown()

tests/unit_tests/provider/test_tool_manager.py

@@ -226,7 +226,7 @@ class TestToolManagerExecuteFuncCall:
 
     @pytest.mark.asyncio
     async def test_execute_raises_when_tool_not_found(self, mock_app_with_loaders, sample_query):
-        """Test that execute_func_call raises ValueError when tool not found."""
+        """Test that execute_func_call raises ToolNotFoundError when tool not found."""
         toolmgr = get_toolmgr_module()
 
         mock_app, mock_plugin_loader, mock_mcp_loader = mock_app_with_loaders
@@ -236,7 +236,7 @@ class TestToolManagerExecuteFuncCall:
         manager = toolmgr.ToolManager(mock_app)
         self._wire_loaders(manager, mock_app, mock_plugin_loader, mock_mcp_loader)
 
-        with pytest.raises(ValueError, match='未找到工具'):
+        with pytest.raises(toolmgr.ToolNotFoundError, match='Tool not found: unknown_tool'):
             await manager.execute_func_call('unknown_tool', {}, sample_query)
 
     @pytest.mark.asyncio