These docs are for version 1.x of Rasa Open Source.

- Trackers maintain the state of a dialogue between the assistant and the user in the form of conversation sessions. To learn more about how to configure the session behavior, check out the docs on [Session configuration](https://legacy-docs-v1.rasa.com/1.10.16/core/domains/#session-config).

### `rasa.core.trackers.DialogueStateTracker`(_sender_id_, _slots_, _max_event_history=None_, _sender_source=None_)
Maintains the state of a conversation.

#### Methods
- `applied_events()`  
Returns all actions that should be applied - w/o reverted events.
- `as_dialogue()`  
Return a `Dialogue` object containing all of the turns, which can be serialised and later used to recover the state of this tracker exactly.
- `change_form_to(_form_name_)`  
Activate or deactivate a form.
- `clear_followup_action()`  
Clears follow up action when it was executed.
- `copy()`  
Creates a duplicate of this tracker.
- `current_slot_values()`  
Return the currently set values of the slots.
- `current_state(_event_verbosity=<EventVerbosity.NONE: 1>_)`  
Return the current tracker state as an object.
- `events_after_latest_restart()`  
Return a list of events after the most recent restart.
- `export_stories(_e2e=False_, _include_source=False_)`  
Dump the tracker as a story in the Rasa Core story format.
- `export_stories_to_file(_export_path='debug.md'_)`  
Dump the tracker as a story to a file.
- `from_dict(_sender_id_, _events_as_dict_, _slots=None_, _max_event_history=None_)`  
Create a tracker from dump.
- `generate_all_prior_trackers()`  
Returns a generator of the previous trackers.
- `get_last_event_for(_event_type_, _action_names_to_exclude=None_, _skip=0_)`  
Gets the last event of a given type which was actually applied.
- `get_latest_entity_values(_entity_type_, _entity_role=None_, _entity_group=None_)`  
Get entity values found for the passed entity type.
- `get_latest_input_channel()`  
Get the name of the input_channel of the latest UserUttered event.
- `get_slot(_key_)`  
Retrieves the value of a slot.
- `idx_after_latest_restart()`  
Return the idx of the most recent restart in the list of events.
- `init_copy()`  
Creates a new state tracker with the same initial values.
- `is_paused()`  
State whether the tracker is currently paused.
- `last_executed_action_has(_name_, _skip=0_)`  
Returns whether last ActionExecuted event had a specific name.
- `past_states(_domain_)`  
Generate the past states of this tracker based on the history.
- `recreate_from_dialogue(_dialogue_)`  
Use a serialised Dialogue to update the trackers state.
- `reject_action(_action_name_)`  
Notify active form that it was rejected.
- `replay_events()`  
Update the tracker based on a list of events.
- `set_form_validation(_validate_)`  
Toggle form validation.
- `set_latest_action_name(_action_name_)`  
Set latest action name and reset form validation and rejection parameters.
- `travel_back_in_time(_target_time_)`  
Creates a new tracker with a state at a specific timestamp.
- `trigger_followup_action(_action_)`  
Triggers another action following the execution of the current.
- `update(_event_, _domain=None_)`  
Modify the state of the tracker according to an `Event`.

### Image

👋 I can help you get started with Rasa and answer your technical questions.