OpenCrust

The secure, lightweight open-source AI agent framework.

A single 17 MB binary that runs your AI agents across Telegram, Discord, Slack, WhatsApp, LINE, and iMessage - with encrypted credential storage, config hot-reload, and 13 MB of RAM at idle. Built in Rust for the security and reliability that AI agents demand.

Why OpenCrust?

vs OpenClaw, ZeroClaw, and other AI agent frameworks

OpenCrustOpenClaw (Node.js)ZeroClaw (Rust)
Binary size17 MB~1.2 GB (with node_modules)~25 MB
Memory at idle13 MB~388 MB~20 MB
Cold start3 ms13.9 s~50 ms
Credential storageAES-256-GCM encrypted vaultPlaintext config filePlaintext config file
Auth defaultEnabled (WebSocket pairing)Disabled by defaultDisabled by default
SchedulingCron, interval, one-shotYesNo
Multi-agent routingPlanned (#108)Yes (agentId)No
Session orchestrationPlanned (#108)YesNo
MCP supportStdioStdio + HTTPStdio
Channels66+4
LLM providers1510+22+
Pre-compiled binariesYesN/A (Node.js)Build from source
Config hot-reloadYesNoNo
WASM plugin systemYes (sandboxed)NoNo

Benchmarks measured on a 1 vCPU, 1 GB RAM DigitalOcean droplet. Reproduce them yourself.

Features

  • LLM Providers: 15 providers - Anthropic Claude, OpenAI, Ollama, and 12 OpenAI-compatible (Sansa, DeepSeek, Mistral, Gemini, Falcon, Jais, Qwen, Yi, Cohere, MiniMax, Moonshot).
  • Channels: Telegram, Discord, Slack, WhatsApp, LINE, iMessage.
  • MCP: Connect any MCP-compatible server for external tools.
  • Personality (DNA): Conversational bootstrap on first message - the agent asks your preferences and writes ~/.opencrust/dna.md. Hot-reloads on edit.
  • Agent Runtime: 6 built-in tools (bash, file_read, file_write, web_fetch, web_search, schedule_heartbeat), memory with vector search, conversation summarization, scheduled tasks.
  • Skills: Define skills as Markdown files.
  • Infrastructure: Config hot-reload, daemonization, self-update, migration tools.
  • Diagnostics: opencrust doctor checks config, credential vault, LLM provider reachability, channel credentials, MCP server connectivity, and database integrity.

Documentation Structure

  • Getting Started: Install and configure OpenCrust.
  • Architecture: Understand the internal design.
  • Channels: Configure communication channels.
  • Providers: Set up LLM providers.
  • Tools: Built-in agent tools reference.
  • MCP: Connect external tools via Model Context Protocol.
  • Security: Learn about security features.
  • Plugins: Extend functionality with WASM plugins.