Stop concatenating skill name + description + body: scoring fields separately lifts skill retrieval to 77.95 Recall@10

arXiv 2608.02880·medium signalXBlueskyLinkedInCopy link

Most skill retrievers flatten a skill into one document before embedding, discarding the fact that name, description, and body each answer a different question about when and how to invoke it. Computing sparse and dense similarity per field and combining the field-level scores — either uniformly or with a small learned MLP — hit 77.95 Recall@10 on SkillRet and 83.78 on SRA-Bench, beating concatenated baselines, with the margin widening as the skill bank grows. If your agent's skill library has crossed a few hundred entries and the right skill stopped surfacing, this is a retrieval-layer fix, not a prompt fix.