What is erii

erii is an AI group chat bot framework built on Kotlin and Ktor. It is not merely a message reply system, but an intelligent agent with comprehensive cognitive capabilities.

erii integrates emotion perception, memory storage, and personality modeling. Its emotional state adapts dynamically to conversation content, with linguistic style adjusting synchronously. It employs an active perception architecture rather than a passive command-response model: by analyzing group atmosphere, it engages or remains silent at appropriate moments, and proactively initiates topics when the group becomes inactive. Through sustained interaction, erii memorizes member preferences and acquires group-specific terminology and expressions.

Core Systems

• Emotion System

  ---

  PAD three-dimensional emotion model (Pleasure, Arousal, Dominance). Real-time emotional adjustment based on conversation content, influencing reply tone, emoji usage, and linguistic style.

• Memory System

  ---

  Multi-dimensional memory (user profiles, preferences, facts, summaries). Semantic retrieval based on vector similarity across three levels: global, group, and member.

• Flow System

  ---

  0-100 flow value quantifying conversational engagement. Rapid entry into focused state upon matching topics of interest, with built-in overheat protection.

• Volition System

  ---

  Proactive speech impulse calculated from multi-dimensional factors including emotion, flow, and keywords. Three modes: Interrupt, Icebreak, and Routine, with situational awareness capability.

• Rule Management

  ---

  Rules stored as Markdown files with hot reload support. Multi-level scope (global > Bot > group). AI may manage rules autonomously via ToolSet.

• Cron System

  ---

  Efficient time-wheel-based task scheduling. Supports one-shot and recurring reminders defined by Cron expressions. AI generates natural reminder text.

• Summary System

  ---

  Automatic generation of group chat conversation summaries. AI extracts key information and topic threads, with historical summary retrieval.

• Evolution System

  ---

  Automatic learning of new vocabulary and trending expressions from group chats. Records semantic meaning and usage context, integrating them naturally at appropriate moments.

Plugin Extensions

erii is built on the PF4J plugin framework and supports four extension points:

Extension Type	Description	Trigger
AgentExtension	General agent extension	Always participates in agent loop
RouteExtension	LLM routing extension	Matched by RoutingAgent intent classification
CmdExtension	Command extension	/xxx command prefix match, supports aliases
PassiveExtension	Passive extension	Background tasks / event listeners

Component Services

Component	Description	Supported Backends
LLM Chat	AI conversational reasoning	Google Gemini / DeepSeek / MiniMax / OpenAI / Anthropic / OpenRouter
Vector Embedding	Text and image semantic vectorization	ByteDance Embedding / SiliconFlow
Web Search	Real-time search for AI Agent	Exa / MiniMax Search
Vision	Image content understanding and description	MiniMax Vision
Browser	Web page screenshots and Markdown scraping	Playwright

Tech Stack

• Backend

  ---

  Kotlin 2.2+ · Ktor 3.3+ · Koin 4.1+ · JobRunr 8.3+ · H2 · Exposed · PF4J 3.15+

• AI Framework

  ---

  Koog Agents 0.7+ · Multi-provider LLM support

• CLI Tool

  ---

  Go 1.21+ · Bubble Tea TUI

• Distribution

  ---

  npm monorepo · Node.js CLI launcher