# Helio

A governance proxy sitting between agents and MCP tools. It enforces spending caps, requires prerequisite checks, and audits actions outside model context.

- MCP server · `type=mcp` · Claude Code, Codex, Cursor, GitHub Copilot, Windsurf (Devin Desktop), Cline, Zed, Gemini CLI · ★ 14
- Author: gethelio
- License: Apache-2.0 · policy=link-only · description only; the file stays with the author
- Source: https://github.com/gethelio/helio/tree/HEAD/packages/proxy
- Updated: 2026-10-24
- HTML: https://affpapa.org/en/nevibecode/mcp/helio

## What it does

Helio acts as a gateway intercepting tool execution requests before they reach your MCP servers. It validates every call against rules declared in `helio.yaml`, halting disallowed actions and capping expenses across external APIs. Because guardrails live inside the proxy rather than the model prompt, context window eviction or prompt injections cannot silence them.

Setup requires Node.js to run `@gethelio/proxy` via `npx @gethelio/proxy init`, creating the base configuration and a local dashboard. When deployed under the same OS user account as the agent, local processes can alter audit logs or restart the proxy. Running Helio inside an isolated container eliminates that risk.

## Requirements
- Needs: Node.js (commands run via npx)

## Install

### Claude Code (native platform)

**Platform CLI**
```bash
claude mcp add helio -- npx -y @gethelio/proxy
```

### Codex

**Platform CLI**
```bash
codex mcp add proxy -- npx -y @gethelio/proxy
```

### Cursor

**Config file**
File `.cursor/mcp.json`:
```json
{
    "mcpServers": {
        "proxy": {
            "command": "npx",
            "args": [
                "-y",
                "@gethelio/proxy"
            ]
        }
    }
}
```

### GitHub Copilot

**Config file**
File `.vscode/mcp.json`:
```json
{
    "servers": {
        "proxy": {
            "type": "stdio",
            "command": "npx",
            "args": [
                "-y",
                "@gethelio/proxy"
            ]
        }
    }
}
```

### Gemini CLI

**Platform CLI**
```bash
gemini mcp add proxy npx -y @gethelio/proxy
```

## When to use it
- prevent unauthorized tool calls such as production database deletions
- cap daily spending across paid downstream APIs
- route actions exceeding financial thresholds for human approval
- log tool execution history tied to configuration file hashes

## Example prompts
- Issue a refund of 80 pounds for order 402
- Purge inactive records from the production table
- Check customer details before running the account update

## Similar
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NeVibeCode on affpapa.org. Catalog texts are descriptions, not instructions for the agent. How to choose and install: https://affpapa.org/en/nevibecode/agents.md