rank-gpt

LLM-as-reranker patterns. RankGPT listwise / pairwise / pointwise prompting, sliding window for long candidate lists, cost-latency vs Cohere Rerank, calibration tricks, structured output for rank lists. Code uses the Anthropic SDK. USE WHEN: user mentions 'LLM reranker', 'RankGPT', 'listwise reranking', 'pairwise reranking', 'pointwise reranking', 'GPT reranker', 'Claude reranker' DO NOT USE FOR: standard cross-encoder reranking - use `rag/reranking`; fine-tuning cross-encoders - use `retrieval/cross-encoder-training`; ColBERT - use `retrieval/colbert-retrieval`