Kavachos: Agent and Human Authentication OS

Kavachos is a comprehensive authentication and authorization library designed for both human users and, uniquely, AI agents. It provides identity management, fine-grained permissions, delegation capabilities, and an immutable audit trail tailored for the 'agentic era'. The current stable version is 0.4.2, with rapid iterative releases addressing features and fixes, as seen by the frequent minor and patch updates between 0.3.0 and 0.4.2. A key differentiator is its dual focus on AI agent identity (cryptographic bearer tokens, wildcard permissions, delegation chains) alongside robust human authentication (14 methods, 27+ OAuth providers, passkeys, SSO). It also functions as a spec-compliant OAuth 2.1 authorization server for the Model Context Protocol (MCP) and is designed to be edge-compatible, running on platforms like Cloudflare Workers, Deno, Bun, and Node.js with a minimal runtime dependency footprint.