v2: Reranking function interface and providers

[oss-amikos]

Context

The Go client has a RerankingFunction interface with multiple provider implementations. The Java client has no reranking support at all.

Missing API

Interface

public interface RerankingFunction {
    String id();
    List<RankedResult> rerank(String query, List<String> documents);
    QueryResult rerankResults(List<String> queryTexts, QueryResult results);
}

public final class RankedResult {
    private final int index;
    private final double score;
    private final String document;
}

Providers

Provider	Description
Cohere	Cohere Reranker API
Jina	Jina AI Reranker
HuggingFace	HuggingFace HFEI Server Reranker
Together	Together AI Reranker

Reference

• Go client: RerankingFunction interface
• Go packages: rerankings/cohere, rerankings/jina, rerankings/hf, rerankings/together