Open Email Harvester

Privacy-first contact extractor for any website, any browser, and any AI.

Scan a page to pull out emails (obfuscated ones too), phone numbers, social/profile links, names, the page title, the source URL and the company domain. Your contacts stay in your browser. If you want an AI assistant to work with them, connect it through MCP or a localhost REST/OpenAPI bridge.

CI workflow: ci/github-actions-ci.yml. Copy it to .github/workflows/ci.yml to enable GitHub Actions (lint + tests on Node 18/20/22 + web-ext lint).

Why it's different

Related MCP server: MCP Google Contacts Server

Features

• Scan the current page with a click or Alt+Shift+E, or turn on auto-scan.

• Extracts emails, phones, social links (GitHub, X/Twitter, Facebook, Instagram, YouTube, Mastodon, Bluesky and more), guessed names, page title, source URL and domain/company.

• Validity hints that work offline: each email is checked for syntax, matched against a disposable-domain list and flagged if it's a role account (info@, support@ and so on). These checks make no network calls.

• Manage your list: duplicates are merged automatically. You can add tags and notes, search everything (or type #tag to filter by tag), filter by type and group by domain.

• Export/import as CSV or JSON, or clear everything.

• Optional sync to the local bridge. It's off by default and only accepts localhost URLs.

Repository layout

extension/   MV3 extension (popup, options, background, content, src/ shared logic)
server/      mcp.js (MCP stdio server), bridge.js (REST), openapi.yaml, db.js
test/        node:test unit tests

Install the extension

First, download open-email-harvester-extension-v1.0.0.zip from Releases and unzip it, or clone this repo and use the extension/ folder.

Chrome / Brave / Opera / Vivaldi

1. Open chrome://extensions (brave://extensions, opera://extensions).

2. Turn on Developer mode.

3. Click Load unpacked and select the extension/ folder.

Microsoft Edge

1. Open edge://extensions.

2. Turn on Developer mode.

3. Click Load unpacked and select extension/.

Firefox (128+)

• To try it temporarily: open about:debugging#/runtime/this-firefox, click Load Temporary Add-on… and pick extension/manifest.json.

• To install it permanently: sign it with npx web-ext sign --source-dir extension using your own AMO credentials, or install it in Developer Edition/Nightly with xpinstall.signatures.required=false.

Using it

1. Open any page and click the toolbar icon, then Scan this page.

2. To scan pages as they load, open Settings, turn on Auto-scan and accept the optional permission.

Connect an AI

You'll need Node 18 or newer. Clone the repo; the server has no runtime dependencies:

git clone https://github.com/tanmayrastogi57/open-email-harvester && cd open-email-harvester

By default, data is stored in ~/.open-email-harvester/contacts.json. To change that, set OEH_DATA.

MCP tools

Claude Desktop

Edit claude_desktop_config.json. It's in ~/Library/Application Support/Claude/ on macOS and %APPDATA%\Claude\ on Windows:

{ "mcpServers": { "open-email-harvester": { "command": "node", "args": ["/ABS/PATH/open-email-harvester/server/mcp.js"] } } }

Restart Claude Desktop.

Cursor

Add the same block to ~/.cursor/mcp.json, or to .cursor/mcp.json in a project.

VS Code (Copilot), Windsurf, Cline, Continue, Zed and other MCP clients

Use stdio transport with the command node /ABS/PATH/server/mcp.js.

ChatGPT, custom GPTs, Gemini, local LLMs and other non-MCP tools

1. Start the bridge:

   node server/bridge.js            # http://127.0.0.1:8765
   OEH_TOKEN=choose-a-secret node server/bridge.js   # optional bearer token

2. Point your tool at the spec: http://127.0.0.1:8765/openapi.yaml (the same file is at server/openapi.yaml).

   • Custom GPT actions: these need a public HTTPS URL. If you want that, expose the bridge yourself through a tunnel and set OEH_TOKEN.

   • Ollama, LM Studio, LangChain, n8n and scripts: call the REST endpoints directly.

Syncing the extension to the bridge

Open extension Settings, turn on Sync, keep the URL as http://127.0.0.1:8765 and enter the token if you set one. New scans are then sent to the bridge, so your AI sees them. The Sync button in the popup pushes everything you've already saved.

REST quick reference

GET    /health
GET    /contacts?query=&tag=&type=email|phone|social&domain=
POST   /contacts                 body: contact or [contacts]
PATCH  /contacts/{id}            body: {tags:[], notes:""}
DELETE /contacts/{id}  |  DELETE /contacts
GET    /domains
GET    /export?format=csv|json
POST   /extract                  body: {text, html, url, title, links[], save}
GET    /validate?email=

Example:

curl -s -X POST localhost:8765/extract -H 'content-type: application/json' \
  -d '{"text":"jane [at] example [dot] com, +1 555 010 0199","save":true}'

Development

npm ci
npm test          # unit tests (node:test)
npm run lint      # eslint
npm run lint:ext  # web-ext lint
npm run package   # builds dist/*.zip

Responsible use

Only collect contact data you're allowed to process, and follow privacy and anti-spam laws (GDPR, CAN-SPAM, etc.) and each site's terms. The tool doesn't get around logins or paywalls. It only reads pages you have open.

License

MIT