claw0

From Zero to One: Build an AI Agent Gateway

10 progressive sections -- every section is a single, runnable Python file. 3 languages (English, Chinese, Japanese) -- code + docs co-located.

What is this?

Most agent tutorials stop at "call an API once." This repository starts from that while loop and takes you all the way to a production-grade gateway.

Build a minimal AI agent gateway from scratch, section by section. 10 sections, 10 core concepts, ~7,000 lines of Python. Each section introduces exactly one new idea while keeping all prior code intact. After all 10, you can read OpenClaw's production codebase with confidence.

s01: Agent Loop           -- The foundation: while + stop_reason
s02: Tool Use             -- Let the model call tools: dispatch table
s03: Sessions & Context   -- Persist conversations, handle overflow
s04: Channels             -- Telegram + Feishu: real channel pipelines
s05: Gateway & Routing    -- 5-tier binding, session isolation
s06: Intelligence         -- Soul, memory, skills, prompt assembly
s07: Heartbeat & Cron     -- Proactive agent + scheduled tasks
s08: Delivery             -- Reliable message queue with backoff
s09: Resilience           -- 3-layer retry onion + auth profile rotation
s10: Concurrency          -- Named lanes serialize the chaos

Architecture

+------------------- claw0 layers -------------------+
|                                                     |
|  s10: Concurrency  (named lanes, generation track)  |
|  s09: Resilience   (auth rotation, overflow compact)|
|  s08: Delivery     (write-ahead queue, backoff)     |
|  s07: Heartbeat    (lane lock, cron scheduler)      |
|  s06: Intelligence (8-layer prompt, hybrid memory)  |
|  s05: Gateway      (WebSocket, 5-tier routing)      |
|  s04: Channels     (Telegram pipeline, Feishu hook) |
|  s03: Sessions     (JSONL persistence, 3-stage retry)|
|  s02: Tools        (dispatch table, 4 tools)        |
|  s01: Agent Loop   (while True + stop_reason)       |
|                                                     |
+-----------------------------------------------------+

Section Dependencies

s01 --> s02 --> s03 --> s04 --> s05
                 |               |
                 v               v
                s06 ----------> s07 --> s08
                 |               |
                 v               v
                s09 ----------> s10

s01-s02: Foundation (no dependencies)
s03: Builds on s02 (adds persistence to the tool loop)
s04: Builds on s03 (channels produce InboundMessages for sessions)
s05: Builds on s04 (routes channel messages to agents)
s06: Builds on s03 (uses sessions for context, adds prompt layers)
s07: Builds on s06 (heartbeat uses soul/memory for prompt)
s08: Builds on s07 (heartbeat output flows through delivery queue)
s09: Builds on s03+s06 (reuses ContextGuard for overflow, model config)
s10: Builds on s07 (replaces single Lock with named lane system)

Quick Start

# 1. Clone and enter
git clone https://github.com/shareAI-lab/claw0.git && cd claw0

# 2. Install dependencies
pip install -r requirements.txt

# 3. Configure
cp .env.example .env
# Edit .env: set ANTHROPIC_API_KEY and MODEL_ID

# 4. Run any section (pick your language)
python sessions/en/s01_agent_loop.py    # English
python sessions/zh/s01_agent_loop.py    # Chinese
python sessions/ja/s01_agent_loop.py    # Japanese

Learning Path

Each section adds exactly one new concept. All prior code stays intact:

Phase 1: FOUNDATION     Phase 2: CONNECTIVITY     Phase 3: BRAIN        Phase 4: AUTONOMY       Phase 5: PRODUCTION
+----------------+      +-------------------+     +-----------------+   +-----------------+   +-----------------+
| s01: Loop      |      | s03: Sessions     |     | s06: Intelligence|  | s07: Heartbeat  |   | s09: Resilience |
| s02: Tools     | ---> | s04: Channels     | --> |   soul, memory, | ->|   & Cron        |-->|   & Concurrency |
|                |      | s05: Gateway      |     |   skills, prompt |  | s08: Delivery   |   | s10: Lanes      |
+----------------+      +-------------------+     +-----------------+   +-----------------+   +-----------------+
 while + dispatch        persist + route            personality + recall  proactive + reliable  retry + serialize

Section Details

| # | Section | Core Concept | Lines | |---|---------|-------------|-------| | 01 | Agent Loop | while True + stop_reason -- that's an agent | ~175 | | 02 | Tool Use | Tools = schema dict + handler map. Model picks a name, you look it up | ~445 | | 03 | Sessions | JSONL: append on write, replay on read. Too big? Summarize old parts | ~890 | | 04 | Channels | Every platform differs, but they all produce the same InboundMessage | ~780 | | 05 | Gateway | Binding table maps (channel, peer) to agent. Most specific wins | ~625 | | 06 | Intelligence | System prompt = files on disk. Swap files, change personality | ~750 | | 07 | Heartbeat & Cron | Timer thread: "should I run?" + queue work alongside user messages | ~660 | | 08 | Delivery | Write to disk first, then send. Crashes can't lose messages | ~870 | | 09 | Resilience | 3-layer retry onion: auth rotation, overflow compaction, tool-use loop | ~1130 | | 10 | Concurrency | Named lanes with FIFO queues, generation tracking, Future-based results | ~900 |

Repository Structure

claw0/
  README.md              English README
  README.zh.md           Chinese README
  README.ja.md           Japanese README
  .env.example           Configuration template
  requirements.txt       Python dependencies
  sessions/              All teaching sessions (code + docs)
    en/                  English
      s01_agent_loop.py  s01_agent_loop.md
      s02_tool_use.py    s02_tool_use.md
      ...                (10 .py + 10 .md)
    zh/                  Chinese
      s01_agent_loop.py  s01_agent_loop.md
      ...                (10 .py + 10 .md)
    ja/                  Japanese
      s01_agent_loop.py  s01_agent_loop.md
      ...                (10 .py + 10 .md)
  workspace/             Shared workspace samples
    SOUL.md  IDENTITY.md  TOOLS.md  USER.md
    HEARTBEAT.md  BOOTSTRAP.md  AGENTS.md  MEMORY.md
    CRON.json
    skills/example-skill/SKILL.md

Each language folder is self-contained: runnable Python code + documentation side by side. Code logic is identical across languages; comments and docs differ.

Prerequisites

Python 3.11+
An API key for Anthropic (or compatible provider)

Dependencies

anthropic>=0.39.0
python-dotenv>=1.0.0
websockets>=12.0
croniter>=2.0.0
python-telegram-bot>=21.0
httpx>=0.27.0

Related Projects

learn-claude-code -- A companion teaching repo that builds an agent framework (nano Claude Code) from scratch in 12 progressive sessions. Where claw0 focuses on gateway routing, channels, and proactive behavior, learn-claude-code dives deep into the agent's internal design: structured planning (TodoManager + nag), context compression (3-layer compact), file-based task persistence with dependency graphs, team coordination (JSONL mailboxes, shutdown/plan-approval FSM), autonomous self-organization, and git worktree isolation for parallel execution. If you want to understand how a production-grade unit agent works inside, start there.

About

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License

MIT

Claw0

Install / Use

README