OpenClaw Architecture Deep Dive: From LLM to Action
In-depth analysis of OpenClaw technical architecture including LLM call chains and tool execution engine.
System Overview
OpenClaw's architecture is designed for flexibility, security, and extensibility. This article provides an in-depth look at how the system processes requests from user input to action execution.
Core Components
┌─────────────────────────────────────────────────────────────────┐
│ OpenClaw Runtime │
├─────────────────────────────────────────────────────────────────┤
│ ┌─────────────┐ ┌─────────────┐ ┌─────────────────────────┐ │
│ │ Message │ │ Context │ │ Tool Executor │ │
│ │ Router │ │ Manager │ │ │ │
│ │ │ │ │ │ ┌─────┐ ┌─────┐ ┌────┐ │ │
│ │ WhatsApp ──┤ │ Memory ────┤ │ │Shell│ │Files│ │API │ │ │
│ │ Telegram ──┤ │ Bootstrap ─┤ │ └─────┘ └─────┘ └────┘ │ │
│ │ Discord ───┤ │ Session ───┤ │ │ │
│ └─────────────┘ └─────────────┘ └─────────────────────────┘ │
│ │ │ ▲ │
│ ▼ ▼ │ │
│ ┌─────────────────────────────────────────────────────────┐ │
│ │ LLM Interface │ │
│ │ ┌─────────┐ ┌─────────────┐ ┌────────────────────┐ │ │
│ │ │ OpenAI │ │ Anthropic │ │ Local (Ollama) │ │ │
│ │ └─────────┘ └─────────────┘ └────────────────────┘ │ │
│ └─────────────────────────────────────────────────────────┘ │
└─────────────────────────────────────────────────────────────────┘
Request Processing Flow
1. Message Ingestion
When a user sends a message:
// Message arrives via platform adapter
{
platform: 'telegram',
userId: '12345',
messageId: 'msg_001',
content: 'Send an email to john about the meeting',
timestamp: 1706400000
}
2. Context Assembly
The Context Manager builds the complete context:
const context = {
// Bootstrap files
system: loadBootstrapFiles(),
// Conversation history
history: getConversationHistory(userId),
// Available tools
tools: mcp.listTools(),
// Current request
userMessage: message.content
};
3. LLM Processing
The assembled context is sent to the LLM:
const response = await llm.complete({
messages: [
{ role: 'system', content: context.system },
...context.history,
{ role: 'user', content: context.userMessage }
],
tools: context.tools,
tool_choice: 'auto'
});
4. Tool Execution
If the LLM requests tool use:
// LLM response includes tool calls
{
content: "I'll send that email for you.",
tool_calls: [{
id: 'call_001',
name: 'gmail_send',
arguments: {
to: '[email protected]',
subject: 'Meeting Update',
body: '...'
}
}]
}
// Tool Executor processes each call
for (const call of response.tool_calls) {
const result = await toolExecutor.run(call);
context.history.push({
role: 'tool',
tool_call_id: call.id,
content: JSON.stringify(result)
});
}
5. Response Synthesis
After tool execution, the LLM synthesizes the final response:
// Final response to user
{
content: "✅ Email sent to [email protected] with subject 'Meeting Update'"
}
Memory Architecture
Short-term Memory
Maintains current conversation context:
class ShortTermMemory {
private messages: Message[] = [];
private maxTokens: number = 8000;
add(message: Message) {
this.messages.push(message);
this.prune(); // Keep within token limit
}
}
Long-term Memory
Persistent storage for cross-session knowledge:
class LongTermMemory {
// Vector store for semantic search
private vectorStore: VectorDB;
// Structured storage for facts
private factStore: KeyValueStore;
async remember(content: string, metadata: object) {
const embedding = await embed(content);
await this.vectorStore.upsert(embedding, content, metadata);
}
async recall(query: string, limit: number = 5) {
const embedding = await embed(query);
return this.vectorStore.search(embedding, limit);
}
}
Tool Execution Engine
Sandboxing
Tools execute in isolated environments:
class ToolSandbox {
// Resource limits
maxMemory: '512MB',
maxCPU: '50%',
timeout: 30000,
// Filesystem restrictions
allowedPaths: ['/workspace', '/tmp'],
deniedPaths: ['/etc', '/var', '/usr'],
// Network restrictions
allowedHosts: ['api.github.com', 'smtp.gmail.com'],
deniedPorts: [22, 23, 3389]
}
Execution Flow
async executeTool(call: ToolCall): Promise {
// 1. Validate permissions
if (!this.checkPermissions(call)) {
return { error: 'Permission denied' };
}
// 2. Apply rate limits
await this.rateLimiter.acquire(call.name);
// 3. Execute in sandbox
const result = await this.sandbox.run(call);
// 4. Log for audit
await this.auditLog.record(call, result);
return result;
}
Conclusion
OpenClaw's architecture balances power with safety, enabling sophisticated agent behaviors while maintaining control and auditability. Understanding these internals helps you build more effective and secure agent configurations.