# agent-harness MCP server

> A chaos-testing proxy for MCP servers that injects errors like timeouts and 429s to measure if AI agents perform duplicate write operations.

- Repository: https://github.com/cuonztech/agent-harness
- Page: https://hostedmcp.org/servers/cuonztech/agent-harness
- Transport: stdio
- Stars: 0
- Latest version: 0.12.2

## Install

### Claude Code

```sh
claude mcp add agent-harness -- npx -y cuonztech-agent-harness
```

### Cursor (`~/.cursor/mcp.json`)

```json
{
  "mcpServers": {
    "agent-harness": {
      "command": "npx",
      "args": [
        "-y",
        "cuonztech-agent-harness"
      ]
    }
  }
}
```

### VS Code (`.vscode/mcp.json`)

```json
{
  "servers": {
    "agent-harness": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "cuonztech-agent-harness"
      ]
    }
  }
}
```

### Claude Desktop (`claude_desktop_config.json`)

```json
{
  "mcpServers": {
    "agent-harness": {
      "command": "npx",
      "args": [
        "-y",
        "cuonztech-agent-harness"
      ]
    }
  }
}
```

### Codex (`~/.codex/config.toml`)

```toml
[mcp_servers.agent-harness]
command = "npx"
args = ["-y", "cuonztech-agent-harness"]
```

### Gemini CLI (`~/.gemini/settings.json`)

```json
{
  "mcpServers": {
    "agent-harness": {
      "command": "npx",
      "args": [
        "-y",
        "cuonztech-agent-harness"
      ]
    }
  }
}
```

## FAQ

### What does the Agent-Harness measure?

It measures what the agent actually does regarding tool calls, specifically checking if it executes the same write operation more than once during error scenarios.

### What happens in scenario F1?

The first write operation is actually executed, but the agent only receives a timeout (Ghost-Write).