CapX — Context Transfer Hub

Transfer full context between AI chat platforms and CLI tools. A browser extension + CLI companion.

Features

• 7 supported platforms: ChatGPT, Claude, Gemini, Perplexity, Grok, DeepSeek, Mistral
• Web → Web: Capture context from one AI chat and inject into another
• Web → CLI: Export context and pipe into opencode, Claude Code, Gemini CLI, or any stdin-based tool
• Full context preservation: Messages, code blocks, images, file references
• Long context handling: Auto-chunking and truncation strategies
• Cloud sync: Optional Supabase sync for cross-device access
• Local-first storage: All data stored in IndexedDB, private by default
• Open source: MIT licensed

Quick Start

Browser Extension

1. Clone the repo
2. pnpm install
3. cd extension && npx wxt build
4. Load the extension/.output/chrome-mv3 directory as an unpacked extension in Chrome

CLI Tool

cd cli
pnpm build

# Format a capsule and pipe into a target CLI
node bin/main.js format opencode --file capsule.json | opencode

# Or inject directly (spawns the target CLI with context piped in)
node bin/main.js inject opencode --file capsule.json

# List capsules in a directory
node bin/main.js list ./capsules

Usage

Capturing Context

1. Open any supported AI chat platform
2. Click the blue Capture Context button (bottom-right corner)
3. Or right-click the page and select "Capture conversation with CapX"
4. The conversation is saved to your local capsule store

Injecting Context

Web to Web:

1. Open the target AI chat platform
2. Click the purple Inject Context button
3. The last captured capsule will be replayed into the chat

Via Popup:

1. Click the CapX extension icon
2. Click "Inject" on any capsule in the list
3. It will be injected into the active tab's chat

Exporting

Use the extension popup to download capsules as:

• JSON — Full structured data, ideal for re-import
• Markdown — Human-readable conversation transcript

Cloud Sync

1. Create a free Supabase project
2. Create a capsules table with columns: id, title, source, model, timestamp, messages, metadata, tags, updated_at
3. Open the CapX popup → click the cloud icon → add your Supabase URL + anon key
4. Use Push to Cloud / Pull from Cloud to sync

Project Structure

capx/
├── packages/capx-core/        # Shared types, schemas, utilities
├── extension/                  # WXT browser extension
│   └── src/
│       ├── entrypoints/        # Background, popup, content scripts
│       ├── content-scripts/    # Per-platform parsers + injectors
│       ├── storage/            # IndexedDB via Dexie.js
│       ├── engine/             # Context normalization and formatting
│       ├── sync/               # Cloud sync adapters
│       └── messages.ts         # Extension message protocol
├── cli/                       # CLI companion tool
│   └── src/
│       ├── main.ts             # CLI entry point
│       ├── formatters.ts       # Output formatters per target
│       └── utils.ts            # File I/O and helpers
└── LICENSE (MIT)

Development

pnpm install
cd extension && npx wxt dev     # Dev mode with HMR
cd cli && pnpm dev -- args...   # Run CLI in dev mode

License

MIT