Opus 5.5 Enables Five-Agent QA Workflow: Test Apps Before Launch with Parallel Subagent Teams

Anthropic's Claude Opus 5.5, released in September 2026, has made it practical to orchestrate multiple specialized subagents in parallel for comprehensive application testing. Developers using Claude Code can now spin up five independent agents—a planner, test writer, browser-QA tester, flaky-test fixer, and reviewer—to stress-test applications before real users encounter them. This workflow represents a shift from single-agent QA to distributed, parallel testing teams within the same development environment.