Sandcastle
Supports UIby metalbear-co
Provide AI agents with safe, isolated access to sandboxed environments for running commands and managing files.
What it does
Sandcastle is an MCP server that bridges the gap between an LLM and a sandboxed environment. Instead of trying to run the model inside the sandbox, Sandcastle allows the agent to live outside and interact with the sandbox via MCP tools, ensuring a clean separation of concerns and security.
Tools
read_file: Read contents of a file within the sandbox.write_file: Write or update files in the sandboxed environment.run_command: Execute shell commands inside the sandbox.manage_secrets: Handle sensitive environment variables and keys securely.
Installation
Add the following to your claude_desktop_config.json:
{
"mcpServers": {
"sandcastle": {
"url": "http://localhost:3000"
}
}
}
Supported hosts
Confirmed for Claude Desktop and any MCP-compliant client (e.g., Claude.ai via HTTPS/ngrok).
Quick install
docker run -p 3000:3000 -e SANDCASTLE_NO_AUTH=1 -e SANDCASTLE_PROVIDERS=local ghcr.io/metalbear-co/sandcastle:nightlyInformation
- Pricing
- free
- Published
- 6/28/2026
- stars
- 0
Categories
Choose your AI client and follow the steps below.
claude-ai
Use ngrok to expose http://localhost:3000 and add the HTTPS URL in Claude.ai Settings → IntegrationsClaude Desktop
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