> ## Documentation Index
> Fetch the complete documentation index at: https://docs.polarity.cc/llms.txt
> Use this file to discover all available pages before exploring further.

# Claude Code

> Connect Paragon to Claude Code via MCP

Add Paragon as an MCP server in Claude Code to get code review, testing, and analysis tools directly in your terminal.

## Prerequisites

* Active Claude subscription (Pro, Max, or API access)
* [Paragon CLI installed](/paragon/overview)

## Get your API key

1. Go to [app.paragon.run](https://app.paragon.run)
2. Sign in or create an account
3. Navigate to **Settings** → **API Keys**
4. Copy your API key

<Note>
  Some tools like `generate_tests`, `run_paragon`, `list_test_suites`, and `save_to_suite` require an API key. Other tools work without one.
</Note>

## Setup

<Steps>
  <Step title="Install Claude Code">
    ```bash theme={null}
    npm install -g @anthropic-ai/claude-code
    ```
  </Step>

  <Step title="Add Paragon as an MCP server">
    Run the following command to register Paragon with Claude Code:

    ```bash theme={null}
    claude mcp add-json paragon '{"command":"paragon","args":["mcp-server"],"env":{"POLARITY_API_KEY":"your-api-key-here"}}'
    ```

    Replace `your-api-key-here` with your API key from [app.paragon.run](https://app.paragon.run).
  </Step>

  <Step title="Verify the server is connected">
    ```bash theme={null}
    claude mcp list
    ```

    You should see `paragon` listed as a configured MCP server.
  </Step>
</Steps>

## Available tools

Once connected, Paragon exposes 12 tools to Claude Code:

### Code review

| Tool                     | Description                                                                                                                                                  |
| ------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `run_paragon`            | Run a Paragon AI prompt — reads/writes files, runs shell commands, and performs complex coding tasks. Requires API key.                                      |
| `list_reviewed_prs`      | List pull requests with Paragon review comments in the current repository. Supports filtering by state (`open`, `closed`, `all`).                            |
| `get_review_comments`    | Get parsed review findings from a PR, including severity, descriptions, file locations, and suggested fixes. Auto-detects PR from current branch if omitted. |
| `resolve_review_comment` | Reply to a review comment and optionally resolve the thread.                                                                                                 |

### Testing

| Tool                    | Description                                                                                                                                                       |
| ----------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `detect_test_framework` | Scan the repository and detect test frameworks in use. Returns framework details, run commands, file patterns, and confidence level.                              |
| `find_tests`            | Discover existing test files using framework-aware file patterns. Returns file paths and count.                                                                   |
| `run_tests`             | Execute unit/integration tests using the detected or specified framework. Returns pass/fail status and full output.                                               |
| `run_e2e_tests`         | Run Playwright E2E tests locally. Installs browsers if needed, optionally starts a dev server, and captures results.                                              |
| `generate_tests`        | Generate unit, integration, or E2E tests using Paragon AI. Detects patterns, writes tests, verifies compilation, runs them, and fixes failures. Requires API key. |

### Test suite management

| Tool               | Description                                                                                |
| ------------------ | ------------------------------------------------------------------------------------------ |
| `list_test_suites` | List your test repositories and suites from the Paragon cloud dashboard. Requires API key. |
| `save_to_suite`    | Save locally generated test files to a Paragon cloud test suite. Requires API key.         |

### Utility

| Tool          | Description                                                                                                        |
| ------------- | ------------------------------------------------------------------------------------------------------------------ |
| `check_setup` | Check if the MCP server is properly configured. Reports the status of the API key, Paragon binary, and GitHub CLI. |

## Usage

After setup, Claude Code can automatically use Paragon tools when relevant. You can also request them directly:

```
> Review the comments on my current PR and fix the issues

> Generate unit tests for src/auth.ts

> Run the test suite and show me what's failing

> Find all Playwright tests and run them in headed mode
```

## Configuration

To update your API key or other environment variables, remove and re-add the server:

```bash theme={null}
claude mcp remove paragon
claude mcp add-json paragon '{"command":"paragon","args":["mcp-server"],"env":{"POLARITY_API_KEY":"your-new-api-key"}}'
```