RETRIEVER Spans

Purpose

RETRIEVER spans represent document/context retrieval operations (vector DB queries, semantic search, keyword search).

Required Attributes

Attribute Reference

Query

Document Schema

Flattening Pattern for Documents

Documents are flattened using zero-indexed notation:

retrieval.documents.0.document.id
retrieval.documents.0.document.content
retrieval.documents.0.document.score
retrieval.documents.1.document.id
retrieval.documents.1.document.content
retrieval.documents.1.document.score
...

Document Metadata

Common metadata fields (stored as JSON string):

{
  "source": "knowledge_base.pdf",
  "page": 42,
  "section": "Introduction",
  "author": "Jane Doe",
  "created_at": "2024-01-15",
  "url": "https://example.com/doc",
  "chunk_id": "chunk_123"
}

Example with metadata:

{
  "retrieval.documents.0.document.id": "doc_123",
  "retrieval.documents.0.document.content": "Machine learning is a method of data analysis...",
  "retrieval.documents.0.document.score": 0.92,
  "retrieval.documents.0.document.metadata": "{\"source\": \"ml_textbook.pdf\", \"page\": 15, \"chapter\": \"Introduction\"}"
}

Ordering

Documents are ordered by index (0, 1, 2, ...). Typically:

• Index 0 = highest scoring document
• Index 1 = second highest
• etc.

Preserve retrieval order in your flattened attributes.

Large Document Handling

For very long documents:

• Consider truncating document.content to first N characters
• Store full content in separate document store
• Use document.id to reference full content

Examples

Basic Vector Search

{
  "openinference.span.kind": "RETRIEVER",
  "input.value": "What is machine learning?",
  "retrieval.documents.0.document.id": "doc_123",
  "retrieval.documents.0.document.content": "Machine learning is a subset of artificial intelligence...",
  "retrieval.documents.0.document.score": 0.92,
  "retrieval.documents.0.document.metadata": "{\"source\": \"textbook.pdf\", \"page\": 42}",
  "retrieval.documents.1.document.id": "doc_456",
  "retrieval.documents.1.document.content": "Machine learning algorithms learn patterns from data...",
  "retrieval.documents.1.document.score": 0.87,
  "retrieval.documents.1.document.metadata": "{\"source\": \"article.html\", \"author\": \"Jane Doe\"}",
  "retrieval.documents.2.document.id": "doc_789",
  "retrieval.documents.2.document.content": "Supervised learning is a type of machine learning...",
  "retrieval.documents.2.document.score": 0.81,
  "retrieval.documents.2.document.metadata": "{\"source\": \"wiki.org\"}",
  "metadata.retriever_type": "vector_search",
  "metadata.vector_db": "pinecone",
  "metadata.top_k": 3
}