OPC Architecture Understanding OPC (Orchestrated Parallel Claude) extends Claude Code it does NOT replace it. Core Concept Claude Code CLI is the execution engine. OPC adds orchestration via: Hooks Intercept Claude Code events (PreToolUse, PostToolUse, SessionStart, etc.) Skills Load prompts into Claude Code Scripts Called by hooks/skills for coordination Database Store state between Claude Code instances How Agents Work When you spawn an agent: 1. Main Claude Code instance (your terminal) runs hook on Task tool 2. Hook calls subprocess.Popen(["claude", " p", "prompt"]) 3. A NEW Claude Code instance spawns as child process 4. Child runs independently, reads/writes to coordination DB 5. Parent tracks child via PID in DB What OPC Is NOT OPC is NOT a separate application OPC does NOT run without Claude Code OPC does NOT intercept Claude API calls directly OPC does NOT modify Claude Code's internal behavior What OPC IS OPC IS hooks that Claude Code loads from .claude/hooks/ OPC IS skills that Claude Code loads from .claude/skills/ OPC IS scripts that hooks/skills call for coordination OPC IS a database backend for state across Claude Code instances Key Files Coordination Flow 1. User runs claude in terminal 2. Claude Code loads hooks from .claude/settings.json 3. User says "spawn a research agent" 4. Claude uses Task tool 5. PreToolUse hook fires, checks resources 6. Hook spawns claude p "research..." as subprocess 7. Hook stores PID in PostgreSQL 8. Child agent runs, writes output to .claude/cache/agents/<id / 9. Child completes, broadcasts "done" to PostgreSQL 10. Parent checks DB, reads child's output file Remember Every "agent" is just another claude p process Hooks intercept events, they don't create new functionality All coordination happens via files and PostgreSQL Claude Code is always the execution engine

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