Rag.Reranker behaviour (rag v0.3.4)

Behaviour for reranking retrieved results.

Rerankers improve retrieval quality by rescoring documents based on relevance to the query.

Usage

# Using Passthrough reranker (no reranking)
reranker = %Rag.Reranker.Passthrough{}
{:ok, docs} = Rag.Reranker.rerank(reranker, query, documents)

# Using LLM-based reranker
reranker = Rag.Reranker.LLM.new()
{:ok, docs} = Rag.Reranker.rerank(reranker, query, documents, top_k: 5)

Document Format

Documents should be maps with the following structure:

%{
  id: any(),           # Unique identifier
  content: String.t(), # The text content
  score: float(),      # Relevance score
  metadata: map()      # Additional metadata
}

Reranker Implementations

Rag.Reranker.Passthrough - Returns documents unchanged
Rag.Reranker.LLM - Uses an LLM to score and rerank documents

Summary

Types

document()

Callbacks

rerank(reranker, query, documents, opts)

Rerank documents based on their relevance to the query.

Functions

rerank(reranker, query, documents, opts \\ [])

Convenience function to rerank documents.

Types

document()

@type document() :: %{id: any(), content: String.t(), score: float(), metadata: map()}

Callbacks

rerank(reranker, query, documents, opts)

@callback rerank(
  reranker :: struct(),
  query :: String.t(),
  documents :: [document()],
  opts :: keyword()
) :: {:ok, [document()]} | {:error, term()}

Rerank documents based on their relevance to the query.

Parameters

reranker - The reranker struct implementing this behaviour
query - The search query string
documents - List of documents to rerank
opts - Additional options (implementation-specific)

Returns

{:ok, reranked_documents} - Documents sorted by relevance
{:error, reason} - If reranking fails

Functions

rerank(reranker, query, documents, opts \\ [])

@spec rerank(struct(), String.t(), [document()], keyword()) ::
  {:ok, [document()]} | {:error, term()}

Convenience function to rerank documents.

Delegates to the appropriate reranker implementation based on the struct type.

Examples

reranker = Rag.Reranker.LLM.new()
{:ok, docs} = Rag.Reranker.rerank(reranker, "What is Elixir?", documents)

# With options
{:ok, docs} = Rag.Reranker.rerank(reranker, query, documents, top_k: 5)