Compaction

Stuffing

Summarization

• Compress history into shorter form
• https://docs.langchain.com/oss/python/langchain/middleware/built-in#summarization
• Stuffing: no summarization at all, just stuff the whole document into the prompt
• Map Reduce: send parallel requests to LLM to summarize each document/part and then integrate it all in a smaller prompt
• Refine: basically a reduce operation. pass "acc + el" to the LLM to summarize

Truncation

• Trim old messages
• dropping old tokens/messages, simplest strategy