System Architecture

Agent3 follows a hybrid Web2 + Web3 design for practicality and trust:

• Off-chain Layer (Performance & Search)

  • A central server hosts APIs for registration, search, and sync.

  • A Postgres database stores structured metadata and embeddings via pgvector.

  • A sync service crawls or ingests agent cards from third-party registries or agent websites.

• On-chain Layer (Integrity & Verifiability)

  • Agent cards and evaluation summaries are stored as objects on Binance Greenfield (cheap & decentralized storage).

  • Each object’s hash + URI is anchored on BSC through a smart contract AgentCardRegistry (functions: register, update, revoke).

  • Anyone can verify that an off-chain card matches its on-chain hash.

• Vector Search Engine

  • Uses embeddings to represent both agent capabilities and evaluation data.

  • Supports hybrid filtering (capabilities, region, pricing) + semantic similarity search.

• Open Protocol

  • Fully supports ERC-8004 so developers can self-host or build custom discovery UIs.

  • Provides REST/GraphQL APIs for easy integration.

This design ensures fast UX for search while maintaining crypto-level auditability .