fix(agent-server/sdk): subagents missing in remote workspace

examples/01_standalone_sdk/42_file_based_subagents.py

@@ -13,7 +13,6 @@
     Agent,
     Conversation,
     Tool,
-    agent_definition_to_factory,
     register_agent,
 )
 from openhands.sdk.subagent import AgentDefinition
@@ -32,7 +31,7 @@
 # 2. Register it in the delegate registry
 register_agent(
     name=grammar_checker.name,
-    factory_func=agent_definition_to_factory(grammar_checker),
+    factory_func=grammar_checker.to_factory(),
     description=grammar_checker.description,
 )
 

openhands-agent-server/openhands/agent_server/conversation_service.py

@@ -27,6 +27,9 @@
 )
 from openhands.sdk.event import MessageEvent
 from openhands.sdk.event.conversation_state import ConversationStateUpdateEvent
+from openhands.sdk.subagent.registry import (
+    register_agent_if_absent,
+)
 from openhands.sdk.utils.cipher import Cipher
 
 
@@ -240,6 +243,20 @@ async def start_conversation(
                     f"{list(request.tool_module_qualnames.keys())}"
                 )
 
+        # Register subagent definitions from the client's registry
+        if request.subagent_definitions:
+            for agent_def in request.subagent_definitions:
+                factory = agent_def.to_factory()
+                if not agent_def.description:
+                    agent_def = agent_def.model_copy(
+                        update={"description": f"Remote agent: {agent_def.name}"}
+                    )
+                register_agent_if_absent(factory, agent_def)
+            logger.info(
+                f"Registered {len(request.subagent_definitions)} subagent "
+                f"definitions for conversation {conversation_id}: "
+                f"{[d.name for d in request.subagent_definitions]}"
+            )
         # Plugin loading is now handled lazily by LocalConversation.
         # Just pass the plugin specs through to StoredConversation.
         # LocalConversation will:

openhands-agent-server/openhands/agent_server/models.py

@@ -21,6 +21,7 @@
     ConfirmationPolicyBase,
     NeverConfirm,
 )
+from openhands.sdk.subagent.schema import AgentDefinition
 from openhands.sdk.utils.models import DiscriminatedUnionMixin, OpenHandsModel
 from openhands.sdk.workspace import LocalWorkspace
 
@@ -108,6 +109,13 @@ class StartConversationRequest(BaseModel):
             "to register the tools for this conversation."
         ),
     )
+    subagent_definitions: list[AgentDefinition] = Field(
+        default_factory=list,
+        description=(
+            "Subagent definitions from the client's registry. These are "
+            "registered on the server so DelegateTool can advertise them."
+        ),
+    )
     plugins: list[PluginSource] | None = Field(
         default=None,
         description=(

openhands-sdk/openhands/sdk/__init__.py

@@ -48,7 +48,6 @@
 )
 from openhands.sdk.plugin import Plugin
 from openhands.sdk.subagent import (
-    agent_definition_to_factory,
     load_agents_from_dir,
     load_project_agents,
     load_user_agents,
@@ -124,7 +123,6 @@
     "load_project_agents",
     "load_user_agents",
     "load_agents_from_dir",
-    "agent_definition_to_factory",
     "load_project_skills",
     "load_skills_from_dir",
     "load_user_skills",

openhands-sdk/openhands/sdk/conversation/impl/local_conversation.py

@@ -373,10 +373,7 @@ def _ensure_plugins_loaded(self) -> None:
 
         # Register file-based agents defined in plugins
         if all_plugin_agents:
-            register_plugin_agents(
-                agents=all_plugin_agents,
-                work_dir=self.workspace.working_dir,
-            )
+            register_plugin_agents(agents=all_plugin_agents)
 
         # Combine explicit hook_config with plugin hooks
         # Explicit hooks run first (before plugin hooks)

openhands-sdk/openhands/sdk/conversation/impl/remote_conversation.py

@@ -635,10 +635,14 @@ def __init__(
 
         if should_create:
             # Import here to avoid circular imports
+            from openhands.sdk.subagent.registry import (
+                get_registered_agent_definitions,
+            )
             from openhands.sdk.tool.registry import get_tool_module_qualnames
 
             tool_qualnames = get_tool_module_qualnames()
             logger.debug(f"Sending tool_module_qualnames to server: {tool_qualnames}")
+            subagent_defs = get_registered_agent_definitions()
             payload = {
                 "agent": agent.model_dump(
                     mode="json", context={"expose_secrets": True}
@@ -652,6 +656,8 @@ def __init__(
                 ).model_dump(),
                 # Include tool module qualnames for dynamic registration on server
                 "tool_module_qualnames": tool_qualnames,
+                # Include subagent definitions for delegate tool on server
+                "subagent_definitions": [d.model_dump() for d in subagent_defs],
                 # Include plugins to load on server
                 "plugins": [p.model_dump() for p in plugins] if plugins else None,
             }

openhands-sdk/openhands/sdk/subagent/__init__.py

@@ -4,7 +4,6 @@
     load_user_agents,
 )
 from openhands.sdk.subagent.registry import (
-    agent_definition_to_factory,
     get_agent_factory,
     get_factory_info,
     register_agent,
@@ -29,5 +28,4 @@
     "get_agent_factory",
     # Agent def and factory
     "AgentDefinition",
-    "agent_definition_to_factory",
 ]