Feature Request: Public API to initialize Chat with history

[vorburger]

Currently, the Chat API in google-genai (Java SDK) does not expose a way to initialize a Chat session with an existing history of messages (e.g., loaded from persistent storage).

When reloading a session from disk (e.g. JSON/YAML), developers currently have to work around this limitation by either:

1. Re-sending all previous messages to the model, which is slow and consumes tokens.
2. Using reflection to manually populate the private comprehensiveHistory and curatedHistory fields in ChatBase, which is fragile and not recommended.

It would be very beneficial to have a public API (e.g., an overload of Chats.create() or a builder method) that accepts an initial List<Content> to restore the conversation state.

[hemasekhar-p]

Hi @vorburger, Thanks for raising this Feature request. After reviewing the current java-genai SDK documentation and source code, there is no public API available to initialize a Chat instance with pre-existing history. we'll be filing a feature request to track this internally.

[priyanahata]

Hi @vorburger

We have a library built on top of genai java sdk that allows you to fully customize the chat history and also saves it automatically using Kryo on every turn so you can resume your session the next time your application restarts. It also supports stateful tools and will preserve the state of your java classess containing the tools, like you can have normal fields or transient fields in your tool class.

I posted some screenshots here a minute ago

#807

We have some documentation here: http://asi.anahata.uno, check the core module for messages, parts,

But basically, yes, you can save the entire context window to a kryo file and reload it any time you want. It supports "soft deleting" any part of the history (like you can undelete a message or a part that you or the model deleted from the conversation). It also provides the model with an index of all the items in your history so the model can also prune any parts of the history whenever it wants.

Hope it helps