Browser Tab Manager

Browser Tab Manager

Prevent duplicate tabs and clean up unused ones. Load this skill BEFORE navigating to a URL and AFTER each browser milestone.

Problem

Without tab management, browser sessions:

• Open duplicate tabs for the same URL, wasting RAM
• Accumulate stale tabs from previous milestones
• Eventually crash on low-resource machines (Colab, VPS)

When to Use

Step 1: Check If URL Already Open (Before Navigate)

BEFORE calling open_browser_url or navigating, the Browser Subagent MUST:

1. List all open tabs — check the current tab's URL and any other tabs
2. Match the target URL against all open tab URLs:
   • Exact match: Switch to that tab instead of opening a new one
   • Same domain + path match (ignore query params): Switch to that tab and reload if needed
   • No match: Proceed with opening a new tab
3. Log the decision:

   🔍 Tab Check: [TARGET_URL]
   → Found existing tab: [yes/no]
   → Action: [switched to tab N / opened new tab]
   → Total open tabs: [N]
   

Instructions for Browser Subagent Task Prompt

When writing the Task for browser_subagent, include this instruction block:

TAB MANAGEMENT RULES:
- Before navigating to any URL, first check all open browser tabs
- If the target URL (or same domain+path) is already open, switch to that tab instead of opening a new one
- After completing the task, report how many tabs are currently open
- If there are more than 3 tabs open, close any tabs that are not needed for the current task
- Always prefer reusing existing tabs over opening new ones

Step 2: Clean Stale Tabs (After Milestone)

AFTER each browser milestone (every ≤10 steps), the Browser Subagent MUST:

1. Count open tabs — if > 3, proceed to cleanup
2. Identify the active tab — the one currently needed
3. Close all other tabs except:
   • The active/current tab
   • Tabs explicitly bookmarked by the task (if any)
4. Report cleanup:

   🧹 Tab Cleanup:
   → Tabs before: [N]
   → Closed: [list of closed tab URLs]
   → Tabs after: [M]
   

Instructions for Browser Subagent Task Prompt

When writing the Task for browser_subagent, include this at the END of the task:

BEFORE RETURNING:
- List all currently open browser tabs
- Close any tabs that are NOT needed for the next milestone
- Keep only the most relevant tab open (max 2 tabs)
- Report: "Tabs cleaned: [closed N tabs, kept M]"

Step 3: Integration with Existing Skills

With browser-preflight (BEFORE launch)

Add to preflight check: count existing browser tabs from previous sessions.

With rule-using-browser (DURING session)

Every milestone task prompt MUST include tab management instructions from Steps 1 & 2.

With browser-cleanup (AFTER session)

Tab cleanup happens automatically when browser processes are killed. No extra action needed.

Quick Reference: Task Prompt Template

Use this template when building Browser Subagent task prompts:

[Your actual task description here]

--- TAB MANAGEMENT ---
1. Before navigating to any URL, check if it's already open in a tab. If yes, switch to it.
2. Do NOT open duplicate tabs for the same URL.
3. If more than 3 tabs are open, close the ones not needed for this task.
4. Before returning, close all tabs except the one most relevant for future work.
5. Report tab status: "Open tabs: [N], Reused: [yes/no], Cleaned: [N closed]"