Regenerate option

[pashna]

What is the right way to implement the "regenerate" option — for the latest response or for one of the previous ones in the conversation?

[DeanChensj]

Hi @pashna , what do you mean by "regenerate option"? Do you mean in ADK web we provide an option for user to reset output of the previous invocation and rerun the query?

[hangfei]

@adk-bot

[adk-bot]

Response from ADK Answering Agent (experimental, answer may be inaccurate)

TLDR: ADK does not have a built-in "regenerate" feature, so you need to implement it at the application level by managing the conversation history. For the latest response, remove the last agent message from the session history and re-run the agent. For a previous response, truncate the history to that point and then re-run the agent.

---

Here's a more detailed explanation of how you can implement the "regenerate" functionality in your application using ADK:

ADK manages conversations using a Session object, which contains a history of Events (like user messages and agent responses) in chronological order. [1, 2] To implement a regenerate feature, your application will need to programmatically modify this list of events.

Regenerating the Latest Response

This is the more straightforward scenario. The process would be:

1. The user requests a regeneration of the last response.
2. Your application retrieves the current session using the SessionService.
3. You would then identify and remove the last event from the session's history, which should be the agent's most recent response.
4. After updating the session, you would call the ADK runner again. The runner will process the now-shortened history and generate a new response to the user's last message.

Regenerating a Previous Response

Regenerating an earlier response in the conversation is more complex because it requires you to decide what to do with the part of the conversation that came after it. The simplest approach is to "roll back" the conversation to that point.

1. The user selects a specific, older agent response to be regenerated.
2. Your application retrieves the session and finds the user message (Event) that prompted the selected agent response.
3. You would then truncate the session's event history, removing all events that occurred after that user message.
4. With the history "rolled back", you call the ADK runner. The agent will then generate a new response based on the state of the conversation at that earlier point.

In both cases, the key is to use your application logic to manage the Session and its events. ADK provides the framework for conversation history management, and you can build features like "regenerate" on top of it by manipulating that history. [3]

[1] publicly accessible HTTPS URL of the document: https://google.github.io/adk-docs/get-started/about/
[2] publicly accessible HTTPS URL of the document: https://google.github.io/adk-docs/sessions/
[3] publicly accessible HTTPS URL of the document: https://google.github.io/adk-docs/sessions/session/

[hangfei]

I think this answer doesn't know about the rewind features yet.

[DeanChensj]

ADK runner now supports rewind_async() which allow you to rewind to a previous invocation, you can rewind and then resend the user query. See:

adk-python/src/google/adk/runners.py

Line 446 in aa77834

async def rewind_async(