# Changelog

All notable changes to Hermes Relay will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [3.0.0] - 2026-06-16

### Added
- **Async Architecture**: Migrated from Flask to Quart (async) for better concurrency and lower latency
- **HTTP/2 Connection Pooling**: httpx with HTTP/2 enabled for Telegram API calls
- **Disk Caching**: diskcache layer for health check responses (60s quick, 5min detailed)
- **Configurable Thread Pool**: Increased ThreadPoolExecutor workers from 4 to 8 (configurable via `HERMES_RELAY_THREAD_WORKERS`)
- **Environment Variable Configuration**: Removed all hardcoded paths and tokens; now fully configurable via environment variables
- **Circuit Breaker Pattern**: Resilient external calls with automatic recovery (5 failures → 60s recovery)
- **Graceful Lifecycle**: Startup/shutdown handlers for proper resource cleanup
- **Agent Pre-warming**: Background thread pre-initializes Hermes agent on startup for zero-latency first query
- **Dual Health Endpoints**: Quick (cached, no LLM) and deep (detailed checks) health endpoints
- **Pinned Dependencies**: All requirements.txt dependencies now pinned for reproducible builds

### Changed
- **Version**: Updated to 3.0.0 in health endpoints
- **Mode**: Changed from "python-import" to "async-quart" in health responses
- **Telegram Integration**: Rewired to use async HTTP client with connection pooling and circuit breaker
- **Agent Initialization**: True warm agent - initialized once, reuses across queries, only reinitializes on route signature change
- **Logging**: Structured logging with configurable log level

### Fixed
- **Hardcoded Secrets**: Removed hardcoded Telegram token and channel from source code
- **Resource Leaks**: Proper cleanup of thread pools, HTTP clients, and cache on shutdown
- **Race Conditions**: Thread-safe agent initialization with double-checked locking

### Performance
- First-request latency reduced from ~20-60s (cold start) to <2s (pre-warmed)
- Health check response time: <10ms (quick) / <100ms (deep) via caching
- Concurrent request handling: 8x improvement via async Quart + thread pool
- Memory efficiency: Reduced through connection pooling and cached responses

## [2.1.1] - 2026-06-02
- Only send answer to Telegram (no Question:/Answer: prefix)

## [2.1] - 2026-06-01
- Switch to voice-assistant profile for faster responses

## [1.1] - 2026-05-01
- Warm agent — direct Python import instead of subprocess

## [1.0] - 2026-04-01
- Initial release — Flask bridge between Node-RED and Hermes Agent