Evaluate versioning control sessions

Measure VCS isolation performance per-agent-mode

When measuring whether agents properly isolate before editing a shared repository.

• · args: JSON object or string with phase configuration

• · JSON object matching declared schema

• · Claude Code Workflow harness (injected globals: agent, parallel, phase, log)
• · Package manager (pnpm/npm/bun) for CI

• · Workflow harness must inject phase(), agent(), parallel() globals
• · args must be a valid plain object (not a string) before phase execution

• · Phase exits early if any agent returns null or throws
• · Subsequent phases cannot recover from prior phase failure