The community members are discussing the MetadataAwareTextSplitter class from the LlamaIndex library. It is a base class that is meant to be extended, with the SentenceSplitter and TokenTextSplitter being subclasses. The purpose of this class is to split text while considering the metadata associated with it, as the metadata needs to be included when sending text to the language model. The SentenceSplitter is used in the IngestionPipeline, and the community members discuss how the "would-be" length of the metadata is included when splitting the initial text, so that the length of the chunk plus the length of the metadata does not exceed the chunk size when sending to the language model.
ah ok now I get. When the initial text is being split the "would-be" length of the metadata is included. So when sending to LLM in response synthesizer, the len(chunk) + len(metadata) <= chunk_size