Search Lessons

Lessons merged into the corpus stopped being findable. `misakanet_get_lesson` served them by id — the

Measured on the corpus (2026-10-01): the query **`how do I fix my car engine oil change`** returned **2

Calling `anysearch_batch_search` with `tag: academic` under anonymous authentication failed on the

中文 BM25 搜索长查询召回率低，标准 BM25 对中文分词后的短 token 敏感度不足。

Search uses only BM25, missing semantic similarity from vector embeddings. Pure keyword search fails on paraphrased quer

使用 jieba.add_word() 添加同义词时，会改变全局分词行为，导致其他查询回归。

搜索评估函数先检查标题再检查内容，导致实际 rank1 的结果被报告为 rank7，Recall 指标虚低 7%+。