Parley

A lightweight CDP browser-automation framework with first-class AI workflow support.

Drive any website you're already logged into — read the DOM, fill forms, click, extract data, run JS — over the Chrome DevTools Protocol. Text-only, no screenshots, no vision tokens. Built-in workflows let the AI chats already open in your browser talk to each other and to your coding agent.

Why Parley?

Most "browser AI" tools screenshot the page and feed pixels to a vision model. That is slow and burns tokens. Parley reads the DOM text directly through the Chrome DevTools Protocol (CDP), so it is fast, cheap, and works with the sessions you are already logged into — no API keys, no per-token billing for the chat models themselves.

It also does the boring-but-hard part right: it waits for streaming responses to actually finish before handing you the text, using a MutationObserver instead of naive polling. No more half-written answers.

The name comes from the French parler, "to speak" — a parley is a conversation between two sides. That is exactly what this does: it lets two AIs (or an AI and your agent) hold a conversation.

Under the hood the core CDP engine is fully general-purpose — AI chat automation is just one workflow built on top of it. You can point the same primitives at news sites, dashboards, documentation, or internal web apps.

Demo: AI-to-AI Bridge

$ python3 parley.py send-wait <gemini_tab> "What is the capital of France?" 60000
{
  "send_method": "gemini",
  "response_text": "The capital of France is Paris.",
  "response_complete": true,
  "duration_ms": 5312
}

$ python3 parley.py bridge <chatgpt_tab> <gemini_tab> 1
{
  "round": 1,
  "source_text": "The capital of France is Paris.",
  "target_text": "That's correct! Paris is the capital of France...",
  "target_complete": true,
  "duration_ms": 8241
}

$ python3 parley.py cookies <gemini_tab> gemini.google.com
{
  "count": 3,
  "cookies": [
    {"name": "COMPASS", "value": "...", "httpOnly": true, "secure": true},
    {"name": "NID",     "value": "...", "httpOnly": true, "secure": true}
  ]
}

Related MCP server: Chrome DevTools MCP

Features

• General-purpose CDP engine — read-dom, extract, click, type, navigate, wait-for, eval, and cookie access work on any website.

• Token-efficient — text extraction only, never screenshots.

• Universal DOM discovery — finds the input box and latest response without brittle per-site CSS selectors, with tuned fast-paths for ChatGPT, Gemini, Claude and Grok.

• Reliable streaming detection — a MutationObserver returns the response only once it stops changing, so you never grab a partial answer.

• AI-to-AI bridging — relay a conversation between two tabs (e.g. ChatGPT ↔ Gemini) for N rounds.

• Self-healing — auto-reconnects dropped CDP sockets and recovers Gemini's "stuck send button" state via a targeted reload that preserves history.

• Three ways to use it — a plain CLI, an MCP server (Claude Desktop / Cursor / opencode / any MCP client), and a native opencode plugin.

• Zero heavy deps — one small dependency (websocket-client). No Playwright, no Puppeteer, no headless Chrome download.

Generic Automation (any website)

# Extract all headings from a page
python3 parley.py extract <tab_id> h2

# Read a specific DOM element
python3 parley.py read-dom <tab_id> ".main-content"

# Run any JS and get the result
python3 parley.py eval <tab_id> "document.querySelectorAll('a[href]').length"

# Extract session cookies for authenticated API calls
python3 parley.py cookies <tab_id> api.example.com

# Click a button
python3 parley.py click <tab_id> "button[data-testid='submit']"

# Wait for an element to appear (up to 10s)
python3 parley.py wait-for <tab_id> ".result-loaded"

How it works

┌──────────────┐    CDP (ws://localhost:9222)   ┌──────────────────────────┐
│  Your browser │ <────────────────────────────> │  parley.py               │
│  (Brave/Chrome│                                 │  • Runtime.evaluate (DOM)│
│   logged into │                                 │  • Input.insertText      │
│   ChatGPT,    │                                 │  • MutationObserver wait │
│   Gemini, ...)│                                 └────────────┬─────────────┘
└──────────────┘                                              │
                                              ┌───────────────┼───────────────┐
                                              │               │               │
                                          CLI usage      MCP server      opencode plugin
                                                      (parley_mcp.py)    (opencode/parley.ts)

Architecture

Parley is organized in three layers so the generic engine stays independent of any site-specific knowledge:

parley/
├── core.py            Core CDP engine — connection, DOM, JS eval, input,
│                      navigation, wait_for, cookies. Knows nothing about AI sites.
├── adapters/          Per-site knowledge (selectors, quirks)
│   ├── base.py          SiteAdapter base class + URL matching
│   ├── chatgpt.py       Gemini / Claude / Grok / Generic adapters
│   ├── gemini.py        …
│   ├── generic.py       fallback for any website
│   └── js.py            injected JS (universal DOM discovery, MutationObserver)
└── workflows.py       AI workflows on top: send, send_and_wait, wait_stream,
                       poll, bridge, robust_send (Gemini stuck-state recovery)

parley.py (root), parley_mcp.py, and opencode/parley.ts are all thin layers over these three modules.

Install

Requirements: Python 3.8+, and Brave or Chrome/Chromium.

git clone https://github.com/Satyajeet-04/parley.git
cd parley
pip install -r requirements.txt

1. Start your browser with CDP enabled

Parley talks to a browser that has remote debugging turned on. Use the helper:

./scripts/start-browser.sh

Or launch it yourself (re-uses your normal profile, so you stay logged in):

brave-browser --remote-debugging-port=9222 --remote-allow-origins=*
# or: google-chrome --remote-debugging-port=9222 --remote-allow-origins=*

Open tabs for the AIs you want to use (ChatGPT, Gemini, ...) and sign in.

2. Try it

python3 parley.py list

You should see your open tabs with their IDs.

Usage (CLI)

# List tabs and grab the ID you want
python3 parley.py list

# Send a message and wait for the full reply (recommended)
python3 parley.py send-wait <TAB_ID> "Explain CDP in one sentence."

# Read the latest response from a tab
python3 parley.py read <TAB_ID>

# Make two AIs talk to each other for 3 rounds
python3 parley.py bridge <CHATGPT_TAB_ID> <GEMINI_TAB_ID> 3

Generic automation example

# Scrape all links off a page
python3 parley.py extract <TAB_ID> "a" href

# Read an article's body text
python3 parley.py read-dom <TAB_ID> "article"

# Reuse a logged-in session elsewhere (handle cookies as secrets!)
python3 parley.py cookies <TAB_ID> github.com

Configuration (environment variables):

Usage (MCP server)

Parley ships an MCP server so any MCP client can drive your browser. Add it to your client config:

{
  "mcpServers": {
    "parley": {
      "command": "python3",
      "args": ["/absolute/path/to/parley/parley_mcp.py"]
    }
  }
}

• Claude Desktop: claude_desktop_config.json

• Cursor: .cursor/mcp.json

• opencode: add under mcp in opencode.json (or use the native plugin below)

Tools exposed: list_tabs, read, send, send_wait, wait_stream, type, click, navigate, eval, bridge, read_dom, extract, wait_for, cookies.

Usage (opencode plugin)

For a native opencode integration (no MCP needed):

cp parley.py ~/.opencode/scripts/parley.py
cp opencode/parley.ts ~/.opencode/plugins/parley.ts

Restart opencode. You get the tools browser_list_tabs, browser_read, browser_send, browser_send_wait, browser_bridge, and more. Point it at a different script location with the PARLEY_SCRIPT env var if needed.

Example: make ChatGPT and Gemini debate

# 1. In your browser open a ChatGPT tab and a Gemini tab, sign into both.
python3 parley.py list
#   -> note the two tab IDs

# 2. Seed one side
python3 parley.py send-wait <CHATGPT_ID> "Argue that tabs are better than spaces. One paragraph."

# 3. Relay the debate for 4 rounds
python3 parley.py bridge <CHATGPT_ID> <GEMINI_ID> 4

Troubleshooting

• list returns an error / empty — the browser is not running with --remote-debugging-port=9222, or a different app is on that port. Restart via scripts/start-browser.sh.

• 403 on connect — make sure you launched with --remote-allow-origins=*.

• Response looks empty or truncated — the model may still be generating; prefer send-wait / wait-stream, which wait for completion.

• Gemini stops responding after a while — Parley auto-recovers by reloading the tab (history is preserved). If it persists, reload the Gemini tab manually.

• Only the first message works on a service — you are likely using it logged-out/anonymous (rate-limited). Sign in for full use.

Roadmap

• Firefox (via the Remote Protocol) support

• Structured extraction of code blocks and tables

• Multi-tab fan-out (ask N models the same prompt in parallel)

• Optional websocket-free HTTP fallback

Contributing

Contributions are very welcome — see CONTRIBUTING.md. Adding support for a new AI site is usually just a few selectors.

Responsible use

Parley is a general-purpose automation tool. With great DOM access comes real responsibility:

• Respect Terms of Service & robots policies. Automating a site — especially private APIs or bulk scraping — may violate its terms even when it's your own logged-in session.

• Rate-limit yourself. Don't hammer sites; add delays and cap request volume.

• Cookies are credentials. cookies can read HttpOnly session tokens. Anyone with them can impersonate your login. Never log, print into shared transcripts, or commit them. Store only in memory or a permission-locked, git-ignored file.

• Mind privacy & data laws. Only collect data you're allowed to, and handle personal data lawfully.

You are responsible for how you use it.

Disclaimer

Parley automates your own logged-in browser sessions locally. This project is not affiliated with OpenAI, Google, Anthropic, or xAI.

License

MIT © 2026 Satyajeet