Hyeonsang Cho d540be7e21
fix(frontend): gate tool-step links through the href scheme allowlist (#5526)
* fix(frontend): gate tool-step links through the href scheme allowlist

The chain-of-thought renderer turned web_fetch args and web_search /
image_search result URLs straight into <a href>. Markdown links already
pass isSafeHref, but these tool-step links bypassed it, so a
prompt-injected tool call could put file:, ms-msdt:, vscode: or other
OS protocol-handler links into the chat. React 19 only rewrites
javascript: hrefs.

All three sites now reuse the markdown allowlist and render an unsafe
URL as plain text (the image thumbnail stays, unlinked). Tests render
MessageGroup for each tool with unsafe schemes plus a web-URL control.

* docs(changelog): note tool-step link scheme gating (#5526)

* fix(frontend): mark omitted tool-step links and guard web_fetch url type

Review follow-up. Tool steps dropped an unsafe URL to bare text, while
markdown and artifact links show a dotted "Unsafe link omitted" span, so
the two surfaces applying the same rule degraded differently. That span
was already duplicated between markdown-link.tsx and artifact-link.tsx;
it is now one UnsafeLink component used by all three renderers. It
passes extra props through so the image tile still works as a Radix
tooltip trigger.

web_fetch also read args.url with a cast only. A non-string url (models
occasionally emit one mid-stream) reached JSX as an object and threw,
taking down the message list. It is now typeof-guarded.

* fix(frontend): default missing tool-call args before rendering steps

Review follow-up. The web_fetch typeof guard dropped the optional
chaining of the cast it replaced, so a tool call without an args object
threw again. Other branches were already exposed the same way: seven
tool kinds (web_fetch, web_search, image_search, read_file, write_file,
str_replace, browser_*) threw on a missing or null args while building
their labels. convertToSteps now defaults args to {} once, so every
ToolCall branch receives an object.
2026-09-18 16:35:16 +08:00
..
2026-01-14 09:58:53 +08:00
2026-02-10 22:07:25 +08:00

DeerFlow Frontend

Like the original DeerFlow 1.0, we would love to give the community a minimalistic and easy-to-use web interface with a more modern and flexible architecture.

Tech Stack

Quick Start

Prerequisites

  • Node.js 22+
  • pnpm 10.26.2+

Installation

# Install dependencies
pnpm install

# Copy environment variables
cp .env.example .env
# Edit .env with your configuration

Development

# Start development server
pnpm dev

# The app will be available at http://localhost:3000

Build & Test

# Type check
pnpm typecheck

# Check formatting
pnpm format

# Apply formatting
pnpm format:write

# Lint
pnpm lint

# Run unit tests
pnpm test

# One-time setup: install Playwright Chromium browser
pnpm exec playwright install chromium

# Run E2E tests (builds and starts production server automatically)
pnpm test:e2e

# Build for production
pnpm build

# Start production server
pnpm start

Site Map

├── /                    # Landing page
├── /chats               # Chat list
├── /chats/new           # New chat page
└── /chats/[thread_id]   # A specific chat page

Configuration

Environment Variables

Key environment variables (see .env.example for full list):

# Backend API URL (optional, uses local Next.js/nginx proxy by default)
NEXT_PUBLIC_BACKEND_BASE_URL="http://localhost:8001"
# LangGraph-compatible API URL (optional, uses local Next.js/nginx proxy by default)
NEXT_PUBLIC_LANGGRAPH_BASE_URL="http://localhost:8001/api"

Project Structure

tests/
├── e2e/                    # E2E tests (Playwright, Chromium, mocked backend)
└── unit/                   # Unit tests (mirrors src/ layout)
src/
├── app/                    # Next.js App Router pages
│   ├── api/                # API routes
│   ├── showcase/           # Allowlisted public read-only demos
│   ├── workspace/          # Main workspace pages
│   └── mock/               # Mock/demo pages
├── components/             # React components
│   ├── ui/                 # Reusable UI components
│   ├── workspace/          # Workspace-specific components
│   ├── landing/            # Landing page components
│   └── ai-elements/        # AI-related UI elements
├── core/                   # Core business logic
│   ├── api/                # API client & data fetching
│   ├── artifacts/          # Artifact management
│   ├── config/              # App configuration
│   ├── i18n/               # Internationalization
│   ├── mcp/                # MCP integration
│   ├── messages/           # Message handling
│   ├── models/             # Data models & types
│   ├── settings/           # User settings
│   ├── skills/             # Skills system
│   ├── threads/            # Thread management
│   ├── todos/              # Todo system
│   └── utils/              # Utility functions
├── hooks/                  # Custom React hooks
├── lib/                    # Shared libraries & utilities
├── server/                 # Server-side code
│   └── better-auth/        # Authentication setup and session helpers
└── styles/                 # Global styles

Scripts

Command Description
pnpm dev Start development server with Webpack
pnpm build Build for production
pnpm start Start production server
pnpm test Run unit tests with Rstest
pnpm test:e2e Run E2E tests with Playwright
pnpm format Check formatting with Prettier
pnpm format:write Apply formatting with Prettier
pnpm lint Run ESLint
pnpm lint:fix Fix ESLint issues
pnpm typecheck Run TypeScript type checking
pnpm check Run both lint and typecheck

Development Notes

  • Uses pnpm workspaces (see packageManager in package.json)
  • Webpack is the default development bundler until the upstream Turbopack PostCSS worker leak is fixed in a stable Next.js release (#5132). Set DEER_FLOW_DEV_BUNDLER=turbo to opt in to Turbopack for local diagnosis, or DEER_FLOW_DEV_BUNDLER=webpack to select Webpack explicitly. Reconsider the default after the stable fix is verified on macOS arm64 and Linux.
  • Environment validation can be skipped with SKIP_ENV_VALIDATION=1 (useful for Docker)
  • Backend API URLs are optional; nginx proxy is used by default in development

License

MIT License. See LICENSE for details.