AgentDB Semantic Vector Search

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LIBRARY-FIRST PROTOCOL (MANDATORY)

Before writing ANY code, you MUST check:

Step 1: Library Catalog

• Location: .claude/library/catalog.json
• If match >70%: REUSE or ADAPT

Step 2: Patterns Guide

• Location: .claude/docs/inventories/LIBRARY-PATTERNS-GUIDE.md
• If pattern exists: FOLLOW documented approach

Step 3: Existing Projects

• Location: D:\Projects\*
• If found: EXTRACT and adapt

Decision Matrix

Match	Action
Library >90%	REUSE directly
Library 70-90%	ADAPT minimally
Pattern exists	FOLLOW pattern
In project	EXTRACT
No match	BUILD (add to library after)

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Overview

Implement semantic vector search with AgentDB for intelligent document retrieval, similarity matching, and context-aware querying. Build RAG systems, semantic search engines, and knowledge bases.

SOP Framework: 5-Phase Semantic Search

Phase 1: Setup Vector Database (1-2 hours)

• Initialize AgentDB
• Configure embedding model
• Setup database schema

Phase 2: Embed Documents (1-2 hours)

• Process document corpus
• Generate embeddings
• Store vectors with metadata

Phase 3: Build Search Index (1-2 hours)

• Create HNSW index
• Optimize search parameters
• Test retrieval accuracy

Phase 4: Implement Query Interface (1-2 hours)

• Create REST API endpoints
• Add filtering and ranking
• Implement hybrid search

Phase 5: Refine and Optimize (1-2 hours)

• Improve relevance
• Add re-ranking
• Performance tuning

Quick Start

import { AgentDB, EmbeddingModel } from 'agentdb-vector-search';

// Initialize
const db = new AgentDB({ name: 'semantic-search', dimensions: 1536 });
const embedder = new EmbeddingModel('openai/ada-002');

// Embed documents
for (const doc of documents) {
  const embedding = await embedder.embed(doc.text);
  await db.insert({
    id: doc.id,
    vector: embedding,
    metadata: { title: doc.title, content: doc.text }
  });
}

// Search
const query = 'machine learning tutorials';
const queryEmbedding = await embedder.embed(query);
const results = await db.search({
  vector: queryEmbedding,
  topK: 10,
  filter: { category: 'tech' }
});

Features

• Semantic Search: Meaning-based retrieval
• Hybrid Search: Vector + keyword search
• Filtering: Metadata-based filtering
• Re-ranking: Improve result relevance
• RAG Integration: Context for LLMs

Success Metrics

• Retrieval accuracy > 90%
• Query latency < 100ms
• Relevant results in top-10: > 95%
• API uptime > 99.9%

MCP Requirements

This skill operates using AgentDB's npm package and API only. No additional MCP servers required.

All AgentDB operations are performed through:

• npm CLI: npx agentdb@latest
• TypeScript/JavaScript API: import { AgentDB } from 'agentdb-vector-search'

Additional Resources

• Full docs: SKILL.md
• AgentDB Vector Search: https://agentdb.dev/docs/vector-search

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Core Principles

AgentDB Semantic Vector Search operates on 3 fundamental principles for building intelligent document retrieval systems:

Principle 1: Meaning Over Keywords

Semantic search retrieves documents based on meaning similarity rather than exact keyword matching, enabling context-aware retrieval.

In practice:

• Generate embeddings for documents using models like OpenAI ada-002 (1536 dimensions) to capture semantic meaning
• Store vectors with rich metadata (title, content, category, tags) to enable hybrid search combining semantic and keyword filters
• Search using query embeddings to find semantically similar documents even when exact keywords differ
• Implement distance metrics (cosine similarity, euclidean) to rank results by semantic relevance rather than keyword frequency

Principle 2: Performance Through Indexing

Build HNSW indexes for 150x faster vector search compared to exhaustive search, essential for production-scale retrieval.

In practice:

• Create HNSW (Hierarchical Navigable Small World) indexes after document ingestion to enable fast approximate nearest neighbor search
• Optimize search parameters (ef_construction, M) based on accuracy vs speed tradeoffs for your use case
• Test retrieval accuracy with evaluation datasets to ensure index parameters maintain >90% recall at top-10 results
• Batch insert operations during document ingestion to amortize indexing overhead across multiple documents

Principle 3: Context-Aware Retrieval

Enhance search with filtering, re-ranking, and hybrid approaches to improve relevance beyond pure vector similarity.

In practice:

• Add metadata filters to search queries (category, date range, author) to constrain results to relevant document subsets
• Implement re-ranking with cross-encoders or relevance models to improve ordering of top-K results after initial retrieval
• Build hybrid search combining vector similarity (semantic) with keyword matching (BM25) for robust retrieval
• Track query-document relevance metrics to continuously improve search quality through user feedback loops

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Common Anti-Patterns

Anti-Pattern	Problem	Solution
Exhaustive Search Without Indexing	Searching all vectors linearly has O(N) complexity, causing query latency to scale linearly with dataset size and becoming unusable at >10k documents	Build HNSW index (Phase 3) to enable approximate nearest neighbor search with O(log N) complexity, achieving <100ms queries at millions of documents
Single-Model Embeddings	Using only vector similarity ignores keyword signals and metadata, causing retrieval to miss exact matches and fail when embeddings don't capture query intent	Implement hybrid search combining vector similarity with keyword search (BM25) and metadata filtering to leverage multiple retrieval signals
Ignoring Retrieval Metrics	Deploying semantic search without measuring precision/recall creates invisible quality issues where search appears to work but returns irrelevant results	Establish retrieval accuracy baselines (>90% recall@10 target) with evaluation datasets and track metrics continuously to detect degradation

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Conclusion

AgentDB Semantic Vector Search enables building production-grade document retrieval systems for RAG applications, knowledge bases, and search engines. By prioritizing meaning over keywords, leveraging HNSW indexing for performance, and implementing context-aware retrieval strategies, it provides the foundation for intelligent information retrieval.

This skill excels at building RAG systems where LLMs need relevant context, semantic search engines for large document collections, and recommendation systems based on content similarity. Use this when keyword search is insufficient because users search by concept rather than exact terms, or when you need to retrieve contextually relevant documents even when query phrasing differs from document text.

The 5-phase framework (setup database, embed documents, build index, implement query interface, refine optimization) provides a systematic path from initial prototype to production deployment with <100ms query latency and >90% retrieval accuracy at scale.