ethan-agent 0.1.5

Ethan — Lightweight personal AI agent with memory, skills, and multi-model support

Ethan Agent

中文文档

A lightweight, extensible personal AI agent built in Python. Designed to run persistently on your own hardware with memory that grows over time, scheduled tasks, and a pluggable tool/skill system.

Ethan combines ideas from OpenClaw (structured agent loop, layered memory), Hermes Agent (self-improving skills, memory consolidation), and nanobot (minimal core, readable codebase).

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Features

Memory system (five layers)

• Hot/warm/cold three-tier sliding window for long-conversation context; older content auto-compressed by a cheap model
• Structured Facts: confidence-scored entries with conflict detection and deduplication (~/.ethan/memory/facts.json)
• Behavioral Procedures: learned from user corrections, loaded every conversation (procedures.json)
• Session Episodes: auto-summarized on exit, supports keyword search (episodes.json)
• User Profile: narrative document storing personal phrases, goals, and agent agreements (user_profile.md)
• Proactive memory write: Agent calls tools mid-conversation to instantly persist anything worth remembering — no waiting for batch processing

Skill system

• Keyword trigger matching, auto-injected into system prompt
• fast_path: true routes matched input to the millisecond fast track
• channels: [lark, web] filters skills by channel so each surface gets only relevant skills
• Hit tracking and correction collection; Heartbeat auto-updates skill content with a cheap model when corrections accumulate
• Agent can create new skills mid-conversation via the skill_create tool

Three-track routing

• fast: short commands + keyword match → minimal prompt + fast_path tools only + 2 iterations
• medium: mid-length messages → full prompt + all tools + 4 iterations
• full: complex tasks → full prompt + all tools + 10 iterations

Scheduler

• Create cron or interval jobs in conversation; SQLite-persisted, survives restarts
• heartbeat.md: write natural-language tasks; the system runs them periodically

Tool system

• Shell execution, web search (DuckDuckGo), web fetch, file I/O, knowledge base
• Tool results over 4 000 chars are auto-summarized by a cheap model before going back to the main model
• Identical calls within the same turn hit an in-memory cache — no duplicate execution

Prompt Caching

• System prompt split into stable layer / dynamic layer; stable layer cached 5 min, token cost drops to 0.1×

Multi-channel

• CLI REPL, Web UI (Next.js), Lark/Feishu (WebSocket, no public IP required)

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Install

Requires Python 3.12+.

pip3 install ethan-agent

Set an API key and start:

ethan provider set anthropic --api-key sk-ant-xxx
ethan

That's it. On first run, default skills and system files are written to ~/.ethan/.

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Quick Start (Docker, recommended for server deployment)

Docker runs backend and Web UI as separate containers, data persisted to a local volume. No need to clone the repository.

Prerequisites

• Docker 20.10+
• Docker Compose v2

1. Download compose file

mkdir ethan-agent && cd ethan-agent
curl -O https://raw.githubusercontent.com/llm011/ethan-agent/main/docker-compose.yml

2. Configure

Create a .env file and add your API keys:

cat > .env << 'EOF'
ANTHROPIC_API_KEY=sk-ant-xxx
# OPENAI_API_KEY=sk-xxx
# OPENAI_BASE_URL=https://api.example.com/v1
AGENT_DEFAULT_MODEL=claude-sonnet-4-6
EOF

3. Start

docker compose up -d

4. Access

• Web UI: http://localhost:3000
• API: http://localhost:8900
• Health check: http://localhost:8900/health

5. Common commands

docker compose logs -f ethan-backend  # tail logs
docker compose restart ethan-backend  # restart backend
docker compose pull && docker compose up -d  # update to latest version
docker compose down                   # stop

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Local Development / Install from Source

Prerequisites

• Python 3.12+
• uv package manager
• Node.js 20+ (Web UI only)

Install

# From PyPI
pip install ethan-agent

# Or from source
git clone https://github.com/llm011/ethan-agent.git
cd ethan-agent
uv sync

Configure

ethan provider set anthropic --api-key sk-ant-xxx
# or
ethan provider set openai_compat --api-key sk-xxx --base-url https://api.example.com/v1

Run

# Interactive REPL
ethan

# Single-turn query
ethan -p "What's the weather in Tokyo?"

# Specify model
ethan -m claude-sonnet-4-6

# Resume last session
ethan -r last

# Start HTTP API server (needed for Web UI)
ethan serve

Web UI (dev mode)

cd web
npm install
npm run dev   # http://localhost:3000

macOS auto-start (launchd)

./deploy/install.sh

---

Architecture

ethan/
├── core/
│   ├── agent.py               # ReAct loop, three-track router (fast/medium/full)
│   ├── config.py              # YAML config (~/.ethan/config.yaml)
│   └── heartbeat.py           # Heartbeat system, periodic maintenance
├── providers/
│   ├── base.py                # Unified interface (Message, ToolCall, BaseProvider)
│   ├── anthropic.py           # Claude native protocol + Prompt Caching
│   ├── openai_compat.py       # OpenAI-compatible protocol
│   └── manager.py             # Route model ID → provider
├── memory/
│   ├── session.py             # Session persistence (SQLite)
│   ├── working.py             # Three-tier sliding window memory
│   ├── facts.py               # Structured Facts (conflict detection + confidence)
│   ├── procedures.py          # Behavioral rules (learned from corrections)
│   ├── episodic.py            # Session episode archive
│   └── consolidator.py        # Compress with cheap model
├── skills/
│   ├── loader.py              # Load skills (directory format + legacy .md)
│   ├── registry.py            # Match (with channel filter) + hit stats
│   ├── stats.py               # Hit count + correction collection
│   ├── updater.py             # Auto-update skill content via cheap model
│   └── generator.py           # Auto-generate skills from sessions
├── tools/
│   ├── base.py                # BaseTool abstract class
│   ├── registry.py            # Registry + concurrent executor + turn cache
│   ├── result_compressor.py   # Auto-summarize long tool output
│   └── builtin/
│       ├── shell.py           # Execute shell commands
│       ├── web_search.py      # DuckDuckGo search
│       ├── web.py             # Fetch & extract web page text
│       ├── file.py            # File read/write/list
│       ├── memory_write.py    # Proactive fact write
│       ├── procedure_write.py # Proactive procedure write
│       ├── profile_update.py  # Update user profile
│       └── skill_create.py    # Create skill mid-conversation
├── scheduler/
│   └── cron.py                # APScheduler with SQLite persistence
└── interface/
    ├── cli.py                 # Typer CLI entry point
    ├── repl.py                # Interactive REPL with prompt_toolkit
    ├── api.py                 # FastAPI HTTP + SSE streaming
    ├── lark_events.py         # Lark WebSocket
    └── commands/              # Subcommands (model, provider, session, skill, schedule)

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Memory System

Ethan uses a five-layer memory architecture:

Layer	Content	Storage
Hot	Last N turns (full messages)	In-memory
Warm	Rolling summary of older turns	In-memory
Cold (Facts)	Key facts extracted across sessions	~/.ethan/memory/facts.json
Procedures	Behavioral rules learned from corrections	~/.ethan/memory/procedures.json
User Profile	Narrative personal context (goals, phrases, agreements)	~/.ethan/memory/user_profile.md

Compression is batched (not per-turn) and uses an automatically inferred cheap model (e.g. Haiku for Claude users, Flash Lite for Gemini users).

Agent proactively writes to all layers mid-conversation via memory_write, procedure_write, and profile_update tools — no waiting for the next compression cycle.

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Skills

Skills are Markdown files loaded from ~/.ethan/skills/. On first run, default skills (channels, deepwiki, lark-im, lark-shared, skills-manager) are automatically copied there from the package.

Both directory format (<name>/SKILL.md + references/) and legacy single-file .md format are supported.

---
name: deploy-checklist
trigger: deploy|ship|release
description: Pre-deployment checklist
fast_path: true       # route to fast track when triggered
channels:             # empty = all channels; list = restrict
  - web
version: "1.0"
---

Steps before deploying:
1. Run tests
2. Check for uncommitted changes
3. ...

When a user message matches a skill's trigger, the skill content is injected into the system prompt. Built-in skills include channels, lark-im, and home-assistant.

Skills accumulate hit stats and user corrections. When corrections reach a threshold (default: 2), the Heartbeat job merges them into the skill file using a cheap model.

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Tools

Tools are pluggable — add a new one without touching the agent loop:

from ethan.tools.base import BaseTool

class MyTool(BaseTool):
    name = "my_tool"
    description = "Does something useful"
    fast_path = False   # set True to make available in fast-track mode
    cacheable = False   # set True to cache identical calls within a turn
    parameters = {"type": "object", "properties": {...}, "required": [...]}

    async def run(self, **kwargs) -> str:
        return "result"

Register it in cli.py and the LLM will automatically use it when relevant.

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CLI Commands

ethan                              Start interactive REPL
ethan -p "..."                     Single-turn query
ethan -m MODEL                     Use specific model
ethan -r last                      Resume last session
ethan serve                        Start HTTP API server

ethan model list|add|remove|default
ethan provider list|set
ethan session list|show|delete
ethan skill list|show|create
ethan schedule list|remove|pause|resume

---

HTTP API

GET  /health                    # Health check
GET  /models                    # Available models
POST /chat                      # Chat (stream: true for SSE)
GET  /sessions                  # Session list
GET  /sessions/{id}             # Session detail + messages
GET  /memory/facts              # Facts list
GET  /memory/episodes           # Episode summaries
GET  /skills                    # Skill list
POST /skills                    # Create skill
POST /skills/evolve             # Trigger skill auto-update
GET  /schedule                  # Scheduled jobs
GET  /system-prompt-preview     # Current system prompt preview
GET  /channels                  # Channel list
GET  /knowledge/search          # Semantic search

---

Configuration

All config lives in ~/.ethan/config.yaml:

providers:
  anthropic:
    api_key: sk-ant-xxx
    base_url: https://api.anthropic.com   # optional
    proxy: null                           # per-provider proxy
  openai_compat:
    api_key: sk-xxx
    base_url: https://api.openai.com/v1

models:
  - id: claude-sonnet-4-6
    provider: anthropic
    description: Claude Sonnet 4.6
    alias: [sonnet]
  - id: gpt-4o
    provider: openai_compat
    alias: [gpt]

network:
  proxy: http://127.0.0.1:7890           # global proxy

defaults:
  model: claude-sonnet-4-6
  agent_name: Ethan
  max_tokens: 4096
  max_tool_iterations: 10
  routing:
    fast_max_length: 12
    medium_max_length: 80
    medium_max_iters: 4
    fast_keywords:
      - "turn off*light"
      - "play music"
    fast_skill_triggers:
      - "home assistant"

Environment variables in .env override config values (useful for secrets).

Config directory layout

~/.ethan/
├── config.yaml          # Main config (providers, models, routing)
├── system/
│   ├── identity.md      # Agent identity (name, role)
│   ├── soul.md          # Behavioral principles
│   └── heartbeat.md     # Heartbeat tasks (natural language)
├── memory/
│   ├── facts.json       # Structured facts
│   ├── procedures.json  # Behavioral rules
│   ├── episodes.json    # Session episode archive
│   └── user_profile.md  # User profile (narrative)
├── skills/              # User-defined skills
│   └── <name>/
│       └── SKILL.md
└── sessions.db          # Session history (SQLite)

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Roadmap

✅ Completed

Core Agent

• Multi-model provider (Anthropic + OpenAI-compatible: Gemini, GPT, Ollama, etc.)
• ReAct agent loop with streaming output
• Three-track router: fast / medium / full, tool result compression, per-turn dedup cache
• Prompt Caching (Anthropic stable-prefix cache_control, ~0.1× input cost)

Five-Layer Memory

• Hot/warm/cold sliding window + cheap-model batch compression
• Structured Facts (confidence scoring + conflict detection)
• Behavioral Procedures (learned from user corrections)
• Session Episode archive (auto-summary, keyword search)
• User Profile — narrative document with five named sections
• Proactive memory write: memory_write, procedure_write, profile_update, skill_create
• Memory context isolation (anti-pollution XML tags)

Skill System

• Dual-source loading (built-in + user-defined) + channel filter (channels field)
• fast_path opt-in, hit stats, correction collection, auto-update (Updater)
• Session-end background Skill generation (Hermes-style)
• Built-in skills: home-assistant, lark-im, channels, deepwiki

Tools

• shell, web_search, web_fetch, file_read/write/list, rg, fd
• Knowledge base (sqlite-vec semantic search), scheduler tools, ACP → Claude Code

Scheduler

• Cron + interval, SQLite persistence, auto-restore on restart
• heartbeat.md: natural-language periodic tasks executed automatically

Channels & API

• Web UI (Next.js): chat timeline, memory, skills, schedule, knowledge, settings
• Tool call timeline (collapsible, with icons + duration)
• Feishu/Lark WebSocket (no public IP required)
• OpenAI-compatible Completions API (/v1/chat/completions) + API key management
• Docker deployment + macOS launchd auto-start

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🚀 Planned

UX Improvements

• Message quoting: quote a previous message in the input box
• User profile settings: avatar upload, display name shown in chat bubbles
• Scheduler suggestions: Agent detects scheduling opportunities in conversation and prompts user with 1-2-3 options
• Scheduler templates: ready-to-use tasks (daily briefing, HA device check, knowledge digest)

Channel Expansion

• WeCom (Enterprise WeChat): alongside Feishu as a second messaging channel
• Mobile UI: bottom tab nav, touch gestures, keyboard inset handling

Coding Agent Integration

• ACP multi-turn optimization: smoother Claude Code / OpenCode / Codex sessions with collapsible tool traces
• MCP client: connect external MCP servers, auto-register tools

Long-term

• Space isolation: separate memory/skills per context (life / work / project)
• Async interrupt: detect new messages during long tasks, respond between tool calls
• Obsidian integration: read/write Obsidian vault as knowledge base

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Documentation

Detailed design docs for each module are in docs/:

• Architecture Overview
• Agent Loop
• Routing
• Provider Layer
• Tool System
• Memory System
• Skill System
• Scheduler
• Interface Layer

License

MIT