Diff Review for Copilot

Inline code review comments for VS Code — review AI-generated changes, submit feedback in batch, and let agents respond.

Add review comments on any line in any file, then submit them all to Copilot, Claude Code, or any AI agent as a structured prompt. Comments include surrounding code context and git diff hunks so the AI knows exactly what changed and what you want fixed. Perfect for reviewing Copilot Edits, PR changes, or any code modifications.

Quick Start

1. Add Review Comments

Open any file → hover on the line gutter → click the + icon → type your feedback (e.g., "rename this variable", "add error handling") → click Add Comment.

2. Review & Manage

Click the status bar (💬 2 open · 1 resolved) to open the comment panel — search, filter, batch-resolve, or navigate to any comment.

3. Submit to AI

• Send to Copilot — click the 📤 button on any thread or use the comment panel to submit all
• Copy to Clipboard — click 📋 to copy the structured prompt, then paste into Claude Code, Codex, or any AI chat
• MCP Server — Claude Code connects directly via MCP for real-time comment interaction

Features

Inline Commenting on Any File

• "+" gutter buttons on every line — add comments on any file type (not just markdown)
• Threaded replies with 👤 User and 🤖 Agent role badges
• Edit comments inline, resolve/reopen threads, delete individual replies
• Send to Copilot button directly on each thread's title bar
• Copy to Clipboard button for pasting into any AI chat

Git Diff Context in Prompts

When you submit comments, the prompt includes the git diff hunk for each commented line — showing what was added, removed, and changed. The AI sees both the current code and the change history:

### Line 15

→ 15 | const userData = await fetchUser(id);

**Git diff:**
```diff
@@ -13,5 +13,5 @@
-const data = fetch('/api/user/' + id);
+const userData = await fetchUser(id);

Comment: Good rename, but add error handling for the await

### Comment Panel (Status Bar)

![Comment Panel](https://github.com/jinqishen0725/diff-review/raw/HEAD/examples/screenshot-panel.png)

Click the status bar to open an interactive panel with:
- **Search/filter** — type to find comments by text or filename
- **Global batch actions** — Submit All, Copy All, Resolve All, Delete Resolved, Clear All
- **Per-file batch actions** — Submit, Copy, Resolve, Delete Resolved scoped to a single file
- **Per-comment actions** — Go to, Send to Copilot, Copy, Resolve, Delete

### Comment Persistence
- Comments **survive window reloads** via VS Code workspace state
- **Branch-scoped** — comments are stored per repository + branch
- Switch branches → comments swap automatically
- New branches **inherit** comments from the parent branch, then diverge independently

### Line Tracking
- Comments **follow the code** when lines are added or removed above them
- CRLF-aware — works correctly on Windows with `\r\n` line endings

### 4 Copilot Language Model Tools
Enable in **Agent Mode → Tools** to let Copilot interact with your review comments:

![Agent Reply](https://github.com/jinqishen0725/diff-review/raw/HEAD/examples/screenshot-agent.png)

| Tool | Description |
|---|---|
| `#listDiffComments` | List all comments with IDs, file locations, status, and thread text |
| `#replyToDiffComment` | Reply to a comment as the agent role |
| `#resolveDiffComment` | Mark a comment as resolved/done |
| `#deleteDiffComment` | Delete a comment thread |

**Example workflow:**

User: "Address all my review comments" Agent: [calls #listDiffComments] → sees 3 open comments [makes code changes based on feedback] [calls #replyToDiffComment] → explains what was changed [calls #resolveDiffComment] → marks each as done

### Claude Code Integration (MCP)
The extension includes an MCP server that Claude Code can connect to for real-time access to review comments.

**Setup:**
```bash
claude mcp add diff-review node /path/to/diff-review/out/mcp-server.js

The MCP server connects to the extension's IPC server — comments are always live (no stale files). Available tools: listDiffComments, replyToDiffComment, resolveDiffComment, deleteDiffComment.

Clipboard Support

Every action that sends to Copilot also has a Copy to Clipboard variant — paste the structured prompt into Claude Code, Codex CLI, ChatGPT, or any AI:

• Per-thread: 📋 button on the thread title bar
• Per-file: Copy action in the comment panel
• Global: "Diff Review: Copy All to Clipboard" in the command palette

Commands

Architecture

src/
  extension.ts   — Comment controller, persistence, IPC server, Copilot tools
  mcp-server.ts  — Standalone MCP server for Claude Code (connects to IPC)

IPC Server: The extension starts a local HTTP server on 127.0.0.1 (random port). The MCP server discovers the port via a temp file. All comment reads/writes go through the extension (single source of truth).

Branch Scoping: Comments are stored under diffReview.state.{repoName}.{branchName} in VS Code's workspace state. Branch switches are detected via the git extension API.

Development

# Install dependencies
npm install

# Build extension + MCP server
npm run build

# Build extension only
npm run build:ext

# Build MCP server only
npm run build:mcp

# Package vsix
npx @vscode/vsce package --no-dependencies --allow-missing-repository

# Deploy to installed extension (dev shortcut)
Copy-Item "out\extension.js" "$HOME\.vscode\extensions\jinqishen.diff-review-0.1.0\out\extension.js" -Force

Version History

License

MIT