Run multiple independent browser tests concurrently to reduce total execution time. Instead of running tests sequentially (sum of all durations), parallel execution runs them simultaneously: total time equals the longest single test.
When to Run in Parallel
Split objectives and run in parallel when:
- An objective has more than 15 steps: long objectives drift; split them
- Tasks are independent: no shared browser state or sequential dependencies
- You’re testing different features: login vs. checkout vs. settings
- You’re testing different user roles: admin flow vs. customer flow
Each sub-objective must be self-contained: it navigates to its own URL, authenticates independently, and asserts its own outcomes.
Sequential Pattern
Run three tests one after another:
kane-cli run "Log in and verify dashboard" --url https://myapp.com --headless --timeout 120
kane-cli run "Search for products and verify results" --url https://myapp.com --headless --timeout 120
kane-cli run "Complete checkout and confirm order" --url https://myapp.com --headless --timeout 120
Parallel Pattern (Shell Background Processes)
#!/bin/bash
RESULTS_DIR=$(mktemp -d)
# Start all tests in background
kane-cli run "Log in and verify dashboard" \
--url https://myapp.com --agent --headless --timeout 120 \
> "$RESULTS_DIR/test1.ndjson" 2>&1 &
kane-cli run "Search for products and verify results" \
--url https://myapp.com --agent --headless --timeout 120 \
> "$RESULTS_DIR/test2.ndjson" 2>&1 &
kane-cli run "Complete checkout and confirm order" \
--url https://myapp.com --agent --headless --timeout 120 \
> "$RESULTS_DIR/test3.ndjson" 2>&1 &
kane-cli run "Verify admin user management page" \
--url https://myapp.com --agent --headless --timeout 120 \
> "$RESULTS_DIR/test4.ndjson" 2>&1 &
# Wait for all to finish
wait
# Parse and print results
echo ""
echo "| # | Test | Status | Steps | Time | Summary |"
echo "|---|------|--------|-------|------|---------|"
i=1
for f in "$RESULTS_DIR"/test*.ndjson; do
result=$(tail -1 "$f")
status=$(echo "$result" | jq -r '.status')
duration=$(echo "$result" | jq -r '.duration')
summary=$(echo "$result" | jq -r '.one_liner')
echo "| $i | $(basename $f .ndjson) | $status | - | ${duration}s | $summary |"
((i++))
done
rm -rf "$RESULTS_DIR"
After all tests complete, present results like this:
🧪 Test Suite: Core Flows
📅 Run at: 2026-04-14 14:30 UTC
| # | Test | Status | Steps | Time | Summary |
|---|------------------------|--------|-------|------|--------------------------------|
| 1 | Login + dashboard | ✅ | 5 | 12s | Welcome banner visible |
| 2 | Product search | ✅ | 7 | 18s | 3 results for 'shoes' |
| 3 | Checkout flow | ❌ | 9 | 25s | Payment form did not load |
| 4 | Admin user management | ✅ | 6 | 15s | Users table loaded (12 rows) |
📊 Pass rate: 3/4 (75%) · Total steps: 27 · Total time: 25s (longest test)
AI Agent Sub-Task Pattern
For AI coding agents (Claude Code, Codex CLI, Gemini CLI), use the agent’s parallel task mechanism to spawn multiple sub-agents simultaneously. Each sub-agent runs one Kane CLI command and returns structured results.
Agent prompt template (give this to each sub-agent):
Run this Kane CLI browser test and report the results:
kane-cli run "<objective>" --agent --headless --timeout 120
After the command completes:
1. Capture the exit code
2. Parse the run_end event (last line of stdout)
3. If status is "failed", read the failing step's screenshot from run_dir
4. Return: { status, steps, duration, summary, session_dir, failure_step, screenshot_path }
Resource Limits
Each parallel Kane CLI instance opens its own Chrome browser. Monitor resources when running many parallel tests:
- Each instance uses ~150–300 MB RAM
- 4 concurrent tests = ~800 MB – 1.2 GB RAM
- Each instance uses its own CDP port (9222–9230)
Start with 4 parallel tests and scale up based on your environment. Always use --headless for parallel runs: multiple visible browser windows cause confusion and unnecessary resource overhead.
