Introduce events for agent config/status updates

decoupling dashboard config computation from the task queue

Resolves #1064

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 Status of the `main` branch. Changes prior to the next official version change will appear here.
 
+* Dashboard:
+  - Decouple configuration computation from the agent's task queue by introducing events for agent config/status updates.
+    This allows the dashboard to display the configuration while the project provided at startup is still initialising. #1064
+    
 # v1.5.1 (2026-05-18)
 
 * General:

src/serena/agent.py

@@ -544,6 +544,7 @@ class SerenaAgent:
         self._project_prompt_status = ProjectPromptProvisionStatus()
         self._session_mode_selection_definition = modes
         self.version = serena_version()
+        self._config_changed_callbacks: list[Callable[[], None]] = []
 
         # obtain serena configuration using the decoupled factory function
         self.serena_config = serena_config or SerenaConfig.from_config_file()
@@ -633,7 +634,7 @@ class SerenaAgent:
 
         # create executor for starting the language server and running tools in another thread
         # This executor is used to achieve linear task execution
-        self._task_executor = TaskExecutor("SerenaAgentTaskExecutor")
+        self._task_executor = TaskExecutor("SerenaAgentTaskExecutor", self._task_completion_callback)
 
         # Initialize the prompt factory
         self.prompt_factory = SerenaPromptFactory()
@@ -659,13 +660,22 @@ class SerenaAgent:
         self._active_tools: AvailableTools
         self._update_active_tools()
 
-        # start the dashboard (web frontend), registering its log handler
-        # should be the last thing to happen in the initialization since the dashboard
-        # may access various parts of the agent
+        # create the dashboard backend (if enabled), which will register callback.
+        dashboard_api: SerenaDashboardAPI | None = None
         if self.serena_config.web_dashboard:
-            self._dashboard_thread, port = SerenaDashboardAPI(
-                get_memory_log_handler(), tool_names, agent=self, tool_usage_stats=self._tool_usage_stats
-            ).run_in_thread(host=self.serena_config.web_dashboard_listen_address)
+            dashboard_api = SerenaDashboardAPI(get_memory_log_handler(), tool_names, agent=self, tool_usage_stats=self._tool_usage_stats)
+
+        # propagate the initial config/state to listeners, particularly to the dashboard API.
+        # Note: The only ongoing task can be the LS initialisation, which does not change the config
+        # This is executed before starting the dashboard thread to ensure that the dashboard
+        # has the correct initial state before can requests come in.
+        self._on_config_changed()
+
+        # start the dashboard backend thread and the dashboard frontend manager (if enabled).
+        # This should be the last thing to happen in the initialization since the dashboard
+        # may access various parts of the agent
+        if dashboard_api:
+            dashboard_thread, port = dashboard_api.run_in_thread(host=self.serena_config.web_dashboard_listen_address)
             self._dashboard_manager = DashboardManager(
                 port,
                 self.serena_config.web_dashboard_listen_address,
@@ -1072,6 +1082,27 @@ class SerenaAgent:
         """
         return self._task_executor.execute_task(task, name=name, logged=logged, timeout=timeout)
 
+    def _task_completion_callback(self) -> None:
+        """
+        Called after every task completion. Tasks potentially change the agent's state/configuration.
+        """
+        self._on_config_changed()
+
+    def _on_config_changed(self) -> None:
+        for callback in self._config_changed_callbacks:
+            try:
+                callback()
+            except Exception as e:
+                log.error(f"Error in config changed callback {callback}: {e}", exc_info=e)
+
+    def register_config_changed_callback(self, callback: Callable[[], None]) -> None:
+        """
+        Registers a callback to be called when the agent configuration has (potentially) changed.
+
+        :param callback: the callback function to register
+        """
+        self._config_changed_callbacks.append(callback)
+
     def is_using_language_server(self) -> bool:
         """
         :return: whether this agent uses language server-based code analysis

src/serena/dashboard.py

@@ -207,7 +207,12 @@ class SerenaDashboardAPI:
         self._news_ready = threading.Event()
         self._setup_routes()
         self._read_news = ReadNews.load()
-        # Fetch remote news in background on startup (non-blocking)
+
+        # register callback for config changes
+        self._current_config_overview: dict[str, Any] | None = None
+        self._agent.register_config_changed_callback(self._on_agent_config_changed)
+
+        # fetch remote news in background on startup (non-blocking)
         threading.Thread(target=self._fetch_news, daemon=True).start()
 
     @property
@@ -272,8 +277,10 @@ class SerenaDashboardAPI:
 
         @self._app.route("/get_config_overview", methods=["GET"])
         def get_config_overview() -> dict[str, Any]:
-            result = self._agent.execute_task(self._get_config_overview, logged=False)
-            return result.model_dump()
+            result = self._current_config_overview
+            if result is None:
+                raise ValueError("Config overview not yet available")
+            return result
 
         @self._app.route("/shutdown", methods=["PUT"])
         def shutdown() -> dict[str, str]:
@@ -468,7 +475,7 @@ class SerenaDashboardAPI:
         if self._tool_usage_stats is not None:
             self._tool_usage_stats.clear()
 
-    def _get_config_overview(self) -> ResponseConfigOverview:
+    def _compute_config_overview(self) -> ResponseConfigOverview:
         from serena.config.context_mode import SerenaAgentContext, SerenaAgentMode
         from serena.tools.tools_base import Tool
 
@@ -596,6 +603,9 @@ class SerenaDashboardAPI:
             serena_version=self._agent.version,
         )
 
+    def _on_agent_config_changed(self) -> None:
+        self._current_config_overview = self._compute_config_overview().model_dump()
+
     def _get_available_languages(self) -> ResponseAvailableLanguages:
         from solidlsp.ls_config import Language
 

src/serena/task_executor.py

@@ -16,7 +16,12 @@ T = TypeVar("T")
 
 
 class TaskExecutor:
-    def __init__(self, name: str):
+    def __init__(self, name: str, task_completion_callback: Callable[[], None] | None = None):
+        """
+        :param name: the name of the task executor, used for logging purposes
+        :param task_completion_callback: an optional callback function that will be called after each task completion
+            (regardless of success, failure, or cancellation)
+        """
         self._task_executor_lock = threading.Lock()
         self._task_executor_queue: list[TaskExecutor.Task] = []
         self._task_executor_thread = Thread(target=self._process_task_queue, name=name, daemon=True)
@@ -24,6 +29,7 @@ class TaskExecutor:
         self._task_executor_task_index = 1
         self._task_executor_current_task: TaskExecutor.Task | None = None
         self._task_executor_last_executed_task_info: TaskExecutor.TaskInfo | None = None
+        self._task_completion_callback = task_completion_callback
 
     class Task(ToStringMixin, Generic[T]):
         def __init__(self, function: Callable[[], T], name: str, logged: bool = True, timeout: float | None = None):
@@ -130,6 +136,13 @@ class TaskExecutor:
                 if task.logged:
                     self._task_executor_last_executed_task_info = self.TaskInfo.from_task(task, is_running=False)
 
+            # call the task completion callback if provided
+            if self._task_completion_callback is not None:
+                try:
+                    self._task_completion_callback()
+                except Exception as e:
+                    log.error(f"Error in task completion callback after executing {task.name}: {e}", exc_info=e)
+
     @dataclass
     class TaskInfo:
         name: str

test/serena/test_dashboard.py

@@ -1,3 +1,4 @@
+from collections.abc import Callable
 from types import SimpleNamespace
 
 from serena.dashboard import SerenaDashboardAPI
@@ -16,6 +17,9 @@ class _DummyAgent:
     def __init__(self, project: SimpleNamespace | None) -> None:
         self._project = project
 
+    def register_config_changed_callback(self, callback: Callable[[], None]) -> None:
+        pass
+
     def execute_task(self, func, *, logged: bool | None = None, name: str | None = None):
         del logged, name
         return func()