Dual-Review MCP (Cursor + Claude Code)

Overview

This repository provides a production-grade MCP (Model Context Protocol) server for Cursor that performs a dual code review over the current Git diff:

• Gets the current Git diff (staged by default)
• Requests a JSON review from Cursor’s model (via a Cursor Project Rule)
• Requests a second JSON review from Claude Code CLI (headless, JSON-only)
• Merges both results into a single Markdown report and computes a 1–10 score

The scoring is severity-weighted and tuned for NestJS/Event-driven architectures.

Quickstart

1. Install prerequisites

• Node.js 18+ and pnpm 9+
• Anthropic Claude Code CLI installed and ANTHROPIC_API_KEY set
• Git repo with staged changes to review

2. Install and build

pnpm i
pnpm lint
pnpm build
pnpm test

3. Start MCP server (for local manual run)

This command runs the server over stdio. Normally Cursor launches this automatically based on .cursor/mcp.json.

pnpm start

4. Configure Cursor

Cursor will pick up the MCP config from .cursor/mcp.json in this repo. Ensure the path to servers/dual-review/dist/index.js remains valid.

5. Use the Project Rule

The rule in .cursor/rules/dual-review.mdc orchestrates the workflow inside Cursor chat: it fetches the Git diff, asks Cursor’s model for a JSON review, calls the MCP tool to ask Claude for a second JSON review, then merges and renders the combined report.

Workspace structure

.
├─ .cursor/
│  ├─ mcp.json
│  └─ rules/
│     └─ dual-review.mdc
├─ servers/
│  └─ dual-review/
│     ├─ src/
│     │  ├─ index.ts
│     │  ├─ merge.ts
│     │  ├─ constants.ts
│     │  └─ env.ts
│     ├─ test/
│     │  └─ merge.test.ts
│     ├─ package.json
│     ├─ tsconfig.json
│     └─ eslint.config.mjs
└─ README.md

Environment variables

• ANTHROPIC_API_KEY must be set for the Claude Code CLI to work.
• Optional:
  • DUAL_REVIEW_STDIO_MAX_BUFFER (bytes) to override default stdio buffer size (default: 10 MiB)
  • DUAL_REVIEW_DEFAULT_MODEL to set a default Claude model when not provided in the tool call

Running in Cursor

1. Open this repository in Cursor
2. Ensure MCP is enabled and the dual-review server is detected
3. Trigger the project rule “Dual Review” from the chat or run it per your Cursor setup

Notes

• The Claude CLI is invoked in non-interactive mode with JSON-only output. Make sure the CLI is on your PATH and authenticated.
• The report’s weighting emphasizes security/correctness/reliability for NestJS/CQRS/event-driven stacks.

Tutorial: Using Dual-Review MCP in Cursor

1. Prerequisites

• Cursor (latest) with MCP enabled
• Node 18+ and pnpm 9+
• Claude Code CLI installed and ANTHROPIC_API_KEY set
• A Git repo with staged changes

2. Install and build

pnpm i
pnpm build

3. Open in Cursor and verify MCP

• Open the repo folder in Cursor
• Check the Tools panel: you should see a server named dual-review with tools enabled
• .cursor/mcp.json is already configured to launch servers/dual-review/dist/index.js

4. Run the standard dual review (Cursor + Claude)

• In Cursor chat, run the Project Rule “Dual Review” (from .cursor/rules/dual-review.mdc). The rule:
  • Fetches the staged git diff (dual-review:git_diff)
  • Asks Cursor’s model to produce a JSON review (schema enforced in the rule)
  • Calls dual-review:review_with_claude to get Claude’s JSON review
  • Calls dual-review:compare_reviews to compute score and render the Markdown report

5. Reverse direction or other CLIs (Claude + Cursor/Codex/OpenAI)

• Use the generic tool dual-review:review_with_command to run any CLI in JSON-only mode. Example:

Tool: dual-review:review_with_command
Args:
{
  "diff": "<your-diff-string>",
  "command": "cursor",             // or "codex" / "openai" / other
  "promptArgName": "-p",
  "outputJsonArgs": ["--output-format", "json"],
  "modelArgName": "--model",
  "model": "<model-id>",
  "extraArgs": []
}

• Then pass the resulting JSON alongside Claude’s JSON into dual-review:compare_reviews.

6. Local manual run (optional)

pnpm start

This starts the MCP stdio server; Cursor normally manages this automatically.

Troubleshooting

• “claude: command not found”: ensure Claude CLI is installed and on PATH; ensure ANTHROPIC_API_KEY is set and valid.
• “Invalid JSON” in reviews: re-run the reviewer step; the rule enforces a strict schema, so any deviation will be rejected.
• “No issues found / empty diff”: ensure you have staged changes; try git add -p and re-run.
• MCP server not visible in Cursor: close and reopen the project or reload MCP Tools; ensure .cursor/mcp.json path is valid.