# Configure the Model Context Protocol (MCP) Server

How to connect DynoCap's MCP server to Claude Desktop, Cursor, and Cline to empower LLMs with safe, local sandboxes.

HTML: https://dynocap.dev/docs/how-to/configure-mcp-server

The **Model Context Protocol (MCP)** enables AI coding assistants like Claude Desktop, Cursor, and Cline to call local tools.

DynoCap includes a first-party MCP server package (`@dynocap/mcp`) that exposes tools for starting tasks, executing commands in an isolated Linux microVM, inspecting diffs, and exporting patches.

---

## Prerequisites

1. DynoCap CLI installed (`brew install baires/tap/dynocap`, the curl installer, or `./scripts/build-macos.sh` from a checkout).
2. The runtime your projects use, prepared with `dynocap doctor --fix ./project` (or `--runtime python:3.14`, for example). When a task omits `runtimes`, DynoCap picks one from the project's files, the same way `clone` does, and falls back to `shell:1` (bash, git, ssh). The task result reports the runtime used.
3. Build the TypeScript packages:
   ```sh
   npm run typecheck
   npm run --prefix sdk/mcp build
   ```

---

## MCP Server Security Policies

By default, `@dynocap/mcp` enforces strict security boundaries:

- **Offline Only by Default:** The LLM cannot allocate network interfaces or connect to external hosts.
- **Opt-in Network Modes:** You must explicitly enable network flags via environment variables when launching the server:
  - `DYNOCAP_MCP_ALLOW_FILTERED=1`: Permits HTTPS access to the task runtime's package registry (`registry.npmjs.org` for node, `pypi.org` and `files.pythonhosted.org` for python, `proxy.golang.org` and `sum.golang.org` for go, and none for `shell:1`) and, for a repository URL, that URL's host.
  - `DYNOCAP_MCP_ALLOW_NAT=1`: Permits unrestricted outbound NAT connectivity.
- **Server-chosen host paths:** `projectPath` must be inside `DYNOCAP_MCP_ROOTS` (default: the server's working directory) and is never the home directory or a dot directory in it. Desktop clients often start servers from `/` or `~`, which leaves no default root, so set `DYNOCAP_MCP_ROOTS` to your project directories.
- **Repository hosts and keys:** `repositoryUrl` must name a host in `DYNOCAP_MCP_GIT_HOSTS` (default `github.com,gitlab.com,bitbucket.org`), and `sshKeyPath` needs `DYNOCAP_MCP_ALLOW_SSH_KEY=1`.

Filtered egress limits destinations, not what leaves: the registries and Git hosts it allows accept uploads. See [What filtered egress does not stop](../explanation/security-and-isolation.mdx#what-filtered-egress-does-not-stop).

---

## Connecting to Claude Desktop

Add DynoCap to your Claude Desktop configuration file:

📁 `~/Library/Application Support/Claude/claude_desktop_config.json`:

```json
{
  "mcpServers": {
    "dynocap": {
      "command": "node",
      "args": ["/Users/YOUR_USER/playground/dynocap/sdk/mcp/dist/bin.js"],
      "env": {
        "DYNOCAP_MCP_ALLOW_FILTERED": "1",
        "DYNOCAP_MCP_ROOTS": "/Users/YOUR_USER/code"
      }
    }
  }
}
```

Restart Claude Desktop. You will see the DynoCap tools appear in the hammer icon list.

---

## Connecting to Cursor

To configure Cursor to use DynoCap:

1. Open **Cursor Settings** -> **Features** -> **MCP Servers**.
2. Click **+ Add New MCP Server**.
3. Set:
   - **Name:** `dynocap`
   - **Type:** `command`
   - **Command:** `node /Users/YOUR_USER/playground/dynocap/sdk/mcp/dist/bin.js`

---

## Connecting to Cline / Roo-Code

In Cline/Roo-Code MCP settings:

```json
{
  "mcpServers": {
    "dynocap": {
      "command": "node",
      "args": ["/Users/YOUR_USER/playground/dynocap/sdk/mcp/dist/bin.js"],
      "env": {
        "DYNOCAP_MCP_ALLOW_FILTERED": "1"
      }
    }
  }
}
```

---

## Available MCP Tools

Once connected, your AI assistant can use the following tools:

| MCP Tool              | Purpose                                                                 |
| :-------------------- | :---------------------------------------------------------------------- |
| `dynocap_task_start`  | Imports a project tree or Git URL into an isolated task sandbox.        |
| `dynocap_task_exec`   | Runs a shell command inside the task's `/workspace`. Streams output.    |
| `dynocap_diff`        | Previews unified Git diffs of modifications made by the agent.          |
| `dynocap_task_finish` | Shuts down the sandbox and saves the verified patch and execution logs. |
| `dynocap_ls`          | Lists active sandboxes and retained task records.                       |
| `dynocap_rm`          | Destroys sandboxes or purges retained task directories.                 |
| `dynocap_run`         | Boots a raw Linux sandbox without a project tree.                       |
| `dynocap_exec`        | Executes a command inside a raw sandbox.                                |
| `dynocap_destroy`     | Destroys a raw sandbox.                                                 |

---

## Typical Prompt Example

You can prompt your assistant like this:

> _"Clone `./my-web-app` into a DynoCap sandbox named `feature-auth`. Run `npm test` inside the sandbox to make sure it's green. Then implement OAuth token validation in `src/auth.js`, verify the tests pass, show me the diff preview, and finish the task."_

The assistant will autonomously invoke `dynocap_task_start`, `dynocap_task_exec`, `dynocap_diff`, and `dynocap_task_finish` safely within the Linux microVM.