CallbackManagerForChainGroup

Whether the callback manager is async.

Add a handler to the callback manager.

Remove a handler from the callback manager.

Set handlers as the only handlers on the callback manager.

Set handler as the only handler on the callback manager.

Run when LLM starts running.

Run when a chat model starts running.

Run when the Retriever starts running.

Run when a chain starts running.

Run when the tool starts running.