# Browser Cookies

> Export, save, and import cookies for isolated browser MCP agents. Use after new logins in isolated browsers to persist sessions across restarts, or to seed isolated browsers from the real Chrome session.

- Skill: `m13v/browser-cookies` (Agent Skill)
- Install (CLI): `npx skillmds@latest add m13v/browser-cookies`
- Raw SKILL.md: https://api.skillmd.com/api/skills/m13v/browser-cookies/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: m13v (https://skillmd.com/u/m13v)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/m13v/browser-cookies

---


# Browser Cookies

Manage cookie persistence for isolated browser MCP agents. Isolated browsers load cookies from `~/.claude/browser-sessions.json` at startup but do not save changes back automatically. This skill handles the export/import cycle.

## Storage

- **Cookie file:** `~/.claude/browser-sessions.json`
- **Format:** Playwright `storageState` JSON (`{ "cookies": [...], "origins": [...] }`)
- **Consumers:** All isolated browser agents (isolated-browser, reddit-agent, twitter-agent, linkedin-agent) load from this file via `storageState` in their config

## Workflow 1: Save cookies FROM an isolated browser

Use this after logging into a new service in the isolated browser. This exports the current session cookies and merges them back into the shared cookie file.

### Step 1: Export cookies from the isolated browser

```javascript
// Call via mcp__isolated-browser__browser_run_code
async (page) => {
  const cookies = await page.context().cookies();
  return JSON.stringify(cookies);
}
```

The result is a large JSON string. Save it to a temp file if it exceeds inline limits.

### Step 2: Merge into browser-sessions.json

Parse the exported cookies and merge them into the existing file. When merging, cookies from the export take precedence (matched by domain + name + path).

```python
import json

# Load exported cookies (from temp file or inline)
with open('/tmp/exported-cookies.json') as f:
    new_cookies = json.load(f)

# Load existing storage state
with open('~/.claude/browser-sessions.json') as f:
    state = json.load(f)

# Build lookup of existing cookies
existing = {}
for c in state.get('cookies', []):
    key = (c['domain'], c['name'], c.get('path', '/'))
    existing[key] = c

# Merge: new cookies overwrite existing, add any new ones
for c in new_cookies:
    key = (c['domain'], c['name'], c.get('path', '/'))
    existing[key] = c

state['cookies'] = list(existing.values())

with open('~/.claude/browser-sessions.json', 'w') as f:
    json.dump(state, f, indent=2)
```

### Step 3: Restart the isolated browser

Close and reopen the isolated browser to load the updated cookies:
1. `mcp__isolated-browser__browser_close`
2. `mcp__isolated-browser__browser_navigate` to the target URL

## Workflow 2: Seed cookies FROM the real Chrome browser

Use this to refresh all cookies from the user's real Chrome session (via playwright-extension). This replaces all cookies in the file.

### Step 1: Export from playwright-extension

```javascript
// Call via mcp__playwright-extension__browser_run_code
async (page) => {
  const cookies = await page.context().cookies();
  return JSON.stringify(cookies);
}
```

### Step 2: Replace cookies in browser-sessions.json

```python
import json

# Parse the exported cookies from the MCP result
# (handle the escaped JSON string from ### Result section)
new_cookies = ...  # parsed cookie array

with open('~/.claude/browser-sessions.json') as f:
    state = json.load(f)

state['cookies'] = new_cookies

with open('~/.claude/browser-sessions.json', 'w') as f:
    json.dump(state, f, indent=2)
```

### Step 3: Restart isolated browsers to pick up new cookies

## Workflow 3: Save cookies after EVERY isolated browser session

**IMPORTANT:** When you finish a browser task that involved any login, form submission, or authentication in the isolated browser, always run Workflow 1 before closing/leaving. This ensures the next isolated browser session has the updated cookies.

## Notes

- Cookies are loaded once at context creation. Changes during a session are only in memory until explicitly saved.
- All isolated browser agents share the same `browser-sessions.json`. Saving from one agent updates cookies for all of them.
- Some httpOnly session-bound cookies may not transfer (e.g., GitHub `user_session`). These require re-login per session.
- Google session cookies (SID, HSID, SSID, APISID, SAPISID, etc.) DO transfer and persist well.