Batch Review

A collaborative code and markdown review tool that bridges human reviewers and AI agents. Both can browse files, inspect git diffs, leave structured comments, and save a final review report — all from the same UI, in real time.

Batch Review UI — file tree on the left, rendered Markdown in the centre, and AI-generated review comments on the right


Features

FeatureDescription
3-panel review UIFile explorer + git changes on the left, viewer in the center, comment thread on the right
Markdown rendering.md files are fully rendered, including GitHub-style math rendered with KaTeX (inline dollar-backtick $`...`$, $$...$$, and fenced math blocks; plain $...$ is left as text to avoid currency and stock-symbol false positives) plus Mermaid fenced diagrams with a toolbar toggle between rendered and source views; highlight any paragraph to add a comment
HTML previewing.html and .htm files render in a sandboxed center-panel preview with scripts disabled; select rendered elements, text, or a visual region to add source-backed comments
PDF viewing.pdf files render in the center panel with page-aware text or region comments and reload support
Syntax highlightingAll common languages via Monaco Editor (Python, TypeScript, Go, Rust, etc.)
Inline git diffClick any changed file to view an inline red/green unified diff
Structured commentsEach comment captures @filename:L10-15 line references automatically, with richer rendered-view anchors where useful
Outdated recoveryWhen a text comment goes stale, refresh its stored highlight from the current file directly from the right panel
AI collaborationMCP server exposes many tools so AI agents can review alongside humans — UI updates live, with on-screen notices for agent-driven comment changes
Dual outputSaves review as both JSON (machine-readable) and Markdown (human-readable)
Resume sessionOn startup, if {output-dir}/{output}.json already exists, comments are loaded automatically
Cross-platformRuns on Windows and Linux

GitHub-style math example

Batch Review renders the same GitHub-style math forms it documents above, including inline dollar-backtick $`...`$ and block $$...$$ equations. Plain $...$ remains text so sentences about prices or stock symbols do not accidentally become math. For example:

Inline: eiπ+1=0`e^{i\pi} + 1 = 0`

θJ(θ)=E(s,a)πθ[θlogπθ(as)R(s,a)]\nabla_\theta J(\theta) = \mathbb{E}_{(s, a) \sim \pi_\theta} \left[\nabla_\theta \log \pi_\theta(a \mid s)\, R(s, a)\right]

Architecture

At runtime, Batch Review is a single Python application that serves the browser UI, exposes REST and WebSocket endpoints for that UI, and optionally exposes the same review session to MCP clients.

flowchart LR CLI["CLI entry point<br/>`uv run batch-review`"] Browser["Browser UI<br/>React + Zustand"] McpHost["MCP host<br/>Cursor / Claude Desktop / VS Code / other clients"] subgraph Backend["Batch Review backend process"] Server["FastAPI app<br/>static frontend `/`<br/>REST `/api/*`<br/>WebSocket `/ws`"] Mcp["FastMCP server<br/>stdio transport<br/>HTTP transport `/mcp`"] State["Shared AppState<br/>repo root, comments, MCP session,<br/>connected WebSocket clients"] end Repo["Git repository under review"] Output["Saved review output<br/>`review_comments.json`<br/>`review_comments.md`"] CLI --> Server CLI --> Mcp Server --> Browser Browser -->|"REST reads/writes"| Server Browser <-->|"live sync"| Server Server --> State Mcp --> State McpHost -->|"stdio or HTTP MCP"| Mcp State -->|"read files, diffs, existing review data"| Repo State -->|"save/load review reports"| Output State -.->|"broadcast UI events"| Browser

Distribution


Requirements


Installation

git clone https://github.com/hevangel/batch-review-mcp.git
cd batch-review-mcp
uv sync

The first run will automatically build the React frontend if frontend/dist/ does not exist (requires Node.js + npm on PATH).


Usage

Standalone mode (browser opens by default)

# Review the current directory
uv run batch-review

# Review a specific git repository
uv run batch-review --root /path/to/your/repo

# Custom host / port
uv run batch-review --root /path/to/repo --host 0.0.0.0 --port 9100

# Specify output filenames
uv run batch-review --root /path/to/repo --output review --output-dir /tmp/reviews
# → saves /tmp/reviews/review.json and /tmp/reviews/review.md

The server auto-selects a free port in the 9000–9999 range if the default port is already in use.

MCP stdio mode (Claude Desktop / Cursor / any MCP client; browser opens by default)

uv run batch-review --mcp --root /path/to/repo

The HTTP server starts in a background thread (so the browser UI remains accessible), your default browser opens to the app URL (same as standalone mode; use --no-browser to skip), and the MCP stdio transport runs in the main thread.

Claude Desktop config (claude_desktop_config.json):

{
  "mcpServers": {
    "batch-review": {
      "command": "uv",
      "args": ["run", "batch-review", "--mcp", "--root", "/path/to/repo"]
    }
  }
}

Official MCP registry

This project includes a root-level server.json for the Model Context Protocol registry (preview). The entry uses registryType": "mcpb": the download URL must be a public GitHub release asset, and fileSha256 must match those bytes exactly (the Release workflow builds the .mcpb on Linux, which can differ from a pack produced on Windows).

Recommended order for a new version (e.g. v0.4.3):

  1. Bump version in pyproject.toml, mcpb/manifest.json, and server.json (top-level version plus packages[0].identifier URL: .../releases/download/v0.4.3/batch-review-mcp-0.4.3.mcpb).
  2. Commit and push that release-prep change to main.
  3. Push the tag (e.g. git tag v0.4.3 && git push origin v0.4.3).
  4. The Release workflow builds the Linux artifacts again, runs scripts/update_server_json_mcpb_sha.py to patch server.json in the workflow workspace from the Linux-built .mcpb, runs scripts/verify_release_mcp_registry.py, creates or updates the GitHub release, publishes server.json to the MCP Registry via GitHub Actions OIDC (mcp-publisher login github-oidc), and publishes the wheel/sdist to PyPI when PYPI_API_TOKEN is configured. If identifier or versions do not match the tag, or if the patched server.json still does not match the Linux-built .mcpb, the job fails so you never publish a broken asset to the registry.

The separate MCP registry preflight (Linux MCPB hash) workflow is now optional. It is still useful when you want to inspect the Linux-built bundle bytes before tagging or debug a registry mismatch, but normal releases no longer require copying a SHA into server.json by hand.

If a tag already exists but the Release workflow itself needed a workflow-only fix, you can rerun it manually from Actions via workflow_dispatch by providing release_tag (for example v0.4.3). That manual path checks out the tag you name, overlays the current release metadata from main, and reuses the existing tag name, so you can recover the release without moving the tag or rebuilding from a different code revision. That rerun path also repairs MCP Registry publication because the workflow republishes server.json from the current main branch metadata and recomputes the Linux fileSha256 before verify/publish.

scripts/build_mcpb.py rewrites the packed archive deterministically after mcpb pack, so the Linux SHA from preflight should match the Linux SHA seen again in the Release workflow for the same source tree.

Local mcp-publisher login github remains useful for one-off manual publishes, but normal tagged releases no longer require workstation device-code confirmation.

CLI flags

FlagDefaultDescription
--root PATHcurrent directoryGit repository to review
--host HOST127.0.0.1Bind address
--port PORT9000Preferred port (auto-increments if busy)
--output NAMEreview_commentsBase filename for saved output (no extension)
--output-dir DIRrepo rootDirectory to write output files
--mcpoffEnable MCP stdio transport
--no-browserfalse (omit)Normal behavior (flag omitted): browser opens automatically ~1.2s after the server is ready in standalone, --dev, and --mcp. Pass --no-browser to disable.
--skip-buildoffSkip the npm build step

UI Walkthrough

Left panel — two tabs

Files tab — lazy directory tree. The first render loads only the first few levels so large repositories stay responsive; expanding a folder loads its children on demand while deeper folders continue hydrating in the background. Click a file to open it in the center panel.

Git tab — lists files changed relative to HEAD with status badges:

Click a changed file to open it in inline diff mode.

Center panel

Right panel

Each comment shows:

The 💾 Save Review button saves all comments to:

When the server starts, if that JSON file already exists it is loaded into the session so you can continue a saved review (invalid files are skipped with a log warning). Loading a saved review from the right-panel folder button also updates the active review stem shown in the footer so subsequent saves target that loaded review name by default.


MCP Tools

AI agents connect via http://localhost:PORT/mcp (HTTP transport) or stdio (--mcp flag).

The MCP surface is intentionally review-first. Batch Review is not trying to be a general repo browser or editor API; it is a shared review-state server for:

A typical agent flow is:

  1. Call get_git_changes()
  2. Call get_git_diff(path) for files worth reviewing
  3. Use get_file_content(path) only when extra non-diff context is needed
  4. Add or update comments, optionally driving the shared UI with open/highlight/jump tools
  5. Save or load the review session with the review file tools

Repo-local MCP host configuration

This repository includes checked-in defaults so common agents can use Batch Review and Playwright together:

ProductConfig fileFormat
Cursor (editor and agent CLI).cursor/mcp.jsonmcpServers with "type": "stdio"
VS Code / GitHub Copilot.vscode/mcp.jsonservers with "type": "stdio" (reference)
Claude Code.mcp.jsonProject mcpServers (stdio)
OpenAI Codex CLI.codex/config.toml[mcp_servers.NAME] stdio blocks (loaded for trusted projects)
Gemini CLI.gemini/settings.jsonTop-level mcpServers (guide)

All definitions run uv run batch-review --mcp --root . --skip-build so the review root is the workspace directory hosts use as the server cwd. Cursor’s agent CLI does not always expand ${workspaceFolder} inside args, so these configs use "." for --root (VS Code may still use ${workspaceFolder} in .vscode/mcp.json, which that host expands).

Verifying stdio MCP

# Smoke test with the official Python MCP client
uv run python scripts/test_mcp_client.py

# Cursor Agent CLI (after install: https://cursor.com/docs/cli )
cd /path/to/batch_review_mcp
agent mcp enable batch-review
agent mcp list-tools batch-review
agent --approve-mcps -p "Your prompt that may call MCP tools"
ToolDescription
init_batch_review_session(coding_agent, model_name?, client_version?)Call first once per MCP connection; registers the host and model. Other tools return an error until this succeeds (except get_config, get_review_web_url, and resource batch-review://server/urls).
get_git_changes()List changed files vs HEAD
get_git_diff(path)Unified diff + original/modified content
add_comment(...)Add a review comment; shows a short notice in the UI
update_comment(comment_id, text)Edit comment body; UI notice
delete_comment(id)Delete a comment; UI notice
clear_all_comments()Remove every in-memory comment at once; UI notice
delete_outdated_comments()Remove comments with outdated true; UI notice
list_comments()List all in-memory comments
recompute_comment_stale()Re-scan files vs highlighted_text and set each comment's outdated flag; UI notice
list_review_files()List stems of *.json reviews in output_dir
load_review_by_stem(stem)Replace comments from {stem}.json; UI notice
save_comments(output_stem?, output_dir?)Save JSON + Markdown report, returns paths
get_file_content(path)Read file content as structured data (content, line_count, language, path) when diff context alone is not enough
list_directory(path)Minimal repo navigation helper for hosts that want the review file tree
open_file_in_ui(path, mode)Open a file in the center panel (view or diff); same path+mode refreshes the view
highlight_in_ui(path, line_start?, line_end?, pdf_page?, region_x1?, …)Source files: line_startline_end (1-based). PDFs: pdf_page + region_* normalized 0–1 on that page. Images: region_* in original pixels (omit pdf_page)
jump_to_comment_in_ui(comment_id)Same as clicking a comment’s @file:L… link: open the file and highlight that anchor
get_config()Return output_stem, output_dir, and web_ui_url (when the server has bound)
get_review_web_url()Return web_ui, websocket, and mcp_http URLs for the running app
(resource)MCP resource URI batch-review://server/urls — same URL JSON as get_review_web_url (resources/read); readable before init_batch_review_session

Agents should call init_batch_review_session immediately after connecting (with a non-empty coding_agent, e.g. Cursor or Claude Desktop). The server enforces this: calling any other tool first yields a clear “call init…” error.

Comment add, update, delete, clear_all_comments, delete_outdated_comments, recompute_comment_stale, and load_review_by_stem also push a dismissible toast at the bottom of the right panel (similar styling to the post-save path hints).


Output formats

JSON (review_comments.json)

[
  {
    "id": "4c66b5fc-...",
    "file_path": "src/auth.py",
    "line_start": 42,
    "line_end": 55,
    "reference": "@src/auth.py:L42-55",
    "text": "Token is never validated — add expiry check.",
    "highlighted_text": "…",
    "outdated": false,
    "created_at": "2026-04-15T10:00:00+00:00"
  }
]

Markdown (review_comments.md)

# Code Review

_Generated: 2026-04-15 10:00 UTC — 3 comment(s)_

---

## src/auth.py

### `@src/auth.py:L42-55`
> Token is never validated — add expiry check.

---

Development

# Backend only (no frontend build needed)
uv run batch-review --root . --skip-build --no-browser

# Frontend dev server (proxies API to port 9000)
cd frontend && npm run dev

# Full production build
cd frontend && npm run build

For contributor documentation, name session_history/ files with the actual date of the AI session that produced the change rather than copying the date from an older entry.


License

MIT