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

## User Guide

- [Installation](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/installation/)
- [Tutorial: Rasa Basics](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/rasa-tutorial/)
- [Tutorial: Building Assistants](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/building-assistants/)
- [Command Line Interface](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/command-line-interface/)
- [Architecture](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/architecture/)
- [Messaging and Voice Channels](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/messaging-and-voice-channels/)
- [Testing Your Assistant](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/testing-your-assistant/)
- [Setting up CI/CD](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/setting-up-ci-cd/)
- [Validate Data](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/validate-files/)
- [Configuring the HTTP API](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/configuring-http-api/)
- [Deploying Your Rasa Assistant](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/how-to-deploy/)
- [Cloud Storage](https://legacy-docs-v1.rasa.com/1.9.6/user-guide/cloud-storage/)

## NLU

- [About](https://legacy-docs-v1.rasa.com/1.9.6/nlu/about/)
- [Using NLU Only](https://legacy-docs-v1.rasa.com/1.9.6/nlu/using-nlu-only/)
- [Training Data Format](https://legacy-docs-v1.rasa.com/1.9.6/nlu/training-data-format/)
- [Language Support](https://legacy-docs-v1.rasa.com/1.9.6/nlu/language-support/)
- [Choosing a Pipeline](https://legacy-docs-v1.rasa.com/1.9.6/nlu/choosing-a-pipeline/)
- [Components](https://legacy-docs-v1.rasa.com/1.9.6/nlu/components/)
- [Entity Extraction](https://legacy-docs-v1.rasa.com/1.9.6/nlu/entity-extraction/)

## Core

- [About](https://legacy-docs-v1.rasa.com/1.9.6/core/about/)
- [Stories](https://legacy-docs-v1.rasa.com/1.9.6/core/stories/)
- [Domains](https://legacy-docs-v1.rasa.com/1.9.6/core/domains/)
- [Responses](https://legacy-docs-v1.rasa.com/1.9.6/core/responses/)
- [Actions](https://legacy-docs-v1.rasa.com/1.9.6/core/actions/)
- [Reminders and External Events](https://legacy-docs-v1.rasa.com/1.9.6/core/reminders-and-external-events/)
- [Policies](https://legacy-docs-v1.rasa.com/1.9.6/core/policies/)
- [Slots](https://legacy-docs-v1.rasa.com/1.9.6/core/slots/)
- [Forms](https://legacy-docs-v1.rasa.com/1.9.6/core/forms/)
- [Retrieval Actions](https://legacy-docs-v1.rasa.com/1.9.6/core/retrieval-actions/)
- [Interactive Learning](https://legacy-docs-v1.rasa.com/1.9.6/core/interactive-learning/)
- [Fallback Actions](https://legacy-docs-v1.rasa.com/1.9.6/core/fallback-actions/)
- [Knowledge Base Actions](https://legacy-docs-v1.rasa.com/1.9.6/core/knowledge-bases/)

## Conversation Design

- [Dialogue Elements](https://legacy-docs-v1.rasa.com/1.9.6/dialogue-elements/dialogue-elements/)
- [Small Talk](https://legacy-docs-v1.rasa.com/1.9.6/dialogue-elements/small-talk/)
- [Completing Tasks](https://legacy-docs-v1.rasa.com/1.9.6/dialogue-elements/completing-tasks/)
- [Guiding Users](https://legacy-docs-v1.rasa.com/1.9.6/dialogue-elements/guiding-users/)

## API Reference

- [Action Server](https://legacy-docs-v1.rasa.com/1.9.6/api/action-server/)
- [HTTP API](https://legacy-docs-v1.rasa.com/1.9.6/api/http-api/)
- [Jupyter Notebooks](https://legacy-docs-v1.rasa.com/1.9.6/api/jupyter-notebooks/)
- [Agent](https://legacy-docs-v1.rasa.com/1.9.6/api/agent/)
- [Custom NLU Components](https://legacy-docs-v1.rasa.com/1.9.6/api/custom-nlu-components/)
- [Rasa SDK](https://legacy-docs-v1.rasa.com/1.9.6/api/rasa-sdk/)
- [Events](https://legacy-docs-v1.rasa.com/1.9.6/api/events/)
- [Tracker](https://legacy-docs-v1.rasa.com/1.9.6/api/tracker/#)
- [Tracker Stores](https://legacy-docs-v1.rasa.com/1.9.6/api/tracker-stores/)
- [Event Brokers](https://legacy-docs-v1.rasa.com/1.9.6/api/event-brokers/)
- [Lock Stores](https://legacy-docs-v1.rasa.com/1.9.6/api/lock-stores/)
- [Training Data Importers](https://legacy-docs-v1.rasa.com/1.9.6/api/training-data-importers/)
- [Featurization of Conversations](https://legacy-docs-v1.rasa.com/1.9.6/api/core-featurization/)
- [TensorFlow Configuration](https://legacy-docs-v1.rasa.com/1.9.6/api/tensorflow_usage/)
- [Migration Guide](https://legacy-docs-v1.rasa.com/1.9.6/migration-guide/)
- [Rasa Open Source Change Log](https://legacy-docs-v1.rasa.com/1.9.6/changelog/)

## Migrate from (beta)

- [Dialogflow](https://legacy-docs-v1.rasa.com/1.9.6/migrate-from/google-dialogflow-to-rasa/)
- [Wit.ai](https://legacy-docs-v1.rasa.com/1.9.6/migrate-from/facebook-wit-ai-to-rasa/)
- [LUIS](https://legacy-docs-v1.rasa.com/1.9.6/migrate-from/microsoft-luis-to-rasa/)
- [IBM Watson](https://legacy-docs-v1.rasa.com/1.9.6/migrate-from/ibm-watson-to-rasa/)

## Reference

- [Glossary](https://legacy-docs-v1.rasa.com/1.9.6/glossary/)

## Tracker

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 behaviour, check out the docs on [Session configuration](https://legacy-docs-v1.rasa.com/1.9.6/core/domains/#session-config).

_class_`rasa.core.trackers.``DialogueStateTracker`( _sender_id_, _slots_, _max_event_history=None_, _sender_source=None_)

Maintains the state of a conversation.

The field max_event_history will only give you these last events, it can be set in the tracker_store

### 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.
- `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 of this tracker.
- `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 and optional role and group in latest message.
- `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`.