# Moss > Moss is a real-time semantic search runtime for AI agents, voice agents, copilots, and multimodal apps. It delivers sub-10ms lookups with zero infrastructure. Built in Rust and WebAssembly. Backed by Y Combinator. Built by InferEdge Inc. ## What Moss Does Moss runs semantic search inside your agent runtime — browser, edge, on-device, or cloud — so retrieval is local, fast, and private. Connect your data once; Moss indexes, distributes, and keeps indexes fresh. No database clusters, no replicas, no DevOps. ## SDKs - JavaScript/TypeScript: npm install @inferedge/moss - Python: pip install inferedge-moss - Package name (JS): @inferedge/moss - Package name (Python): inferedge-moss ## Authentication Moss uses project-based credentials. Get your MOSS_PROJECT_ID and MOSS_PROJECT_KEY from the Moss Portal at https://portal.usemoss.dev. Set them as environment variables. ## Embedding Models - moss-minilm (default): Fast, lightweight, ideal for edge/offline use - moss-mediumlm: Higher accuracy with reasonable performance - Bring Your Own Embeddings (BYOE): Pass pre-computed embeddings via DocumentInfo.embedding at index time and QueryOptions.embedding at query time. Use any external model (OpenAI, Cohere, local, etc.). See python/custom_embedding_sample.py. ## Key Concepts - Index: A searchable structure built from your documents. Supports multiple indexes per project. - Document: Has id (string), text (string), and optional metadata (string map). Upserts replace matching ids. - Retrieval: Supports vector similarity (semantic), keyword/BM25, and hybrid search. Controlled via alpha parameter (1.0 = pure semantic, 0.0 = pure keyword). - Storage: Indexes stored on-device by default. Optional cloud sync for backup and sharing. - Client Lifecycle: Create index -> Load index -> Query -> Upsert/Delete docs -> Delete index when done. ## Getting Started - [Quickstart Guide](https://docs.moss.dev/docs/start/quickstart): Install SDK, configure credentials, create and query an index in minutes - [What is Moss?](https://docs.moss.dev/docs/start/what-is-moss): Overview and architecture - [Core Concepts](https://docs.moss.dev/docs/start/core-concepts): Index, Document, Embeddings, Retrieval, Storage explained ## Documentation - [SDK Overview](https://docs.moss.dev/docs/reference/sdk): High-level SDK guide with examples in JS and Python - [JS SDK Reference](https://docs.moss.dev/docs/reference/js/api): Full TypeScript API — MossClient class, interfaces, types - [MossClient API (JS)](https://docs.moss.dev/docs/reference/js/classes/MossClient): Complete method reference — createIndex, loadIndex, query, addDocs, deleteDocs, getDocs, getIndex, listIndexes, deleteIndex, getJobStatus - [API Reference (REST)](https://docs.moss.dev/docs/api-reference/v1/getting-started/introduction): Control Plane API at https://service.usemoss.dev/v1 ## Integration Guides - [Authentication](https://docs.moss.dev/docs/integrate/authentication): Setting up project credentials - [Indexing Data](https://docs.moss.dev/docs/integrate/indexing-data): Creating indexes, upserting documents, choosing models, chunking tips - [Retrieval](https://docs.moss.dev/docs/integrate/retrieval): Semantic, keyword, and hybrid search with alpha tuning and metadata filters - [Storage & Persistence](https://docs.moss.dev/docs/integrate/storage-persistence): Local storage, cloud sync, backup strategies - [Deployment / Production](https://docs.moss.dev/docs/integrate/deployment-production): Production checklist, security, observability ## Use Cases - [Sub-10ms Knowledge Retrieval](https://docs.moss.dev/docs/build/offline-first-search): Offline-first search for knowledge bases - [Voice Agent with LiveKit](https://docs.moss.dev/docs/integrations/livekit): Build a voice AI agent with Moss + LiveKit + OpenAI + Deepgram ## Pricing - Developer (Free): $5/month free credits, build & index datasets, unlimited local queries, shared infra - Hobbyist ($30/mo): Continuous sync engine, unlimited projects & indexes, session replays (7 days), file uploads - Start-up ($200/mo): Hot path cloud search, 150 concurrent sessions, session replays (30 days), priority ingest, email support - Enterprise (Custom): Custom scale, white glove onboarding, 99.9% SLA, SSO, 24/7 Slack support, SOC2 & HIPAA compliance - Details: https://www.moss.dev/pricing ## Sample Code - GitHub: https://github.com/usemoss/moss-samples - JS samples: javascript/comprehensive_sample.ts, javascript/load_and_query_sample.ts - Python samples: python/comprehensive_sample.py, python/load_and_query_sample.py, python/custom_embedding_sample.py (BYOE) ## Links - [Website](https://www.moss.dev) - [Documentation](https://docs.moss.dev/docs) - [Moss Portal](https://portal.usemoss.dev) - [GitHub](https://github.com/usemoss) - [Discord](https://moss.link/discord) - [Release Notes](https://docs.moss.dev/docs/changelog) ## Legal - [Privacy Policy](https://docs.moss.dev/docs/privacy) - [Terms of Service](https://docs.moss.dev/docs/tos) ## Company Moss is built by InferEdge Inc., based in San Francisco, CA. Backed by Y Combinator. Trusted by 500+ teams including Microsoft, EPAM, UC Berkeley, Carnegie Mellon, Podium, and Stanford.