Concurrent Agent Loop
Treats concurrent sessions as OS threads sharing a common event bus and memory address space. Every cycle includes execution, independent peer evaluation, friction tracking, self-assessment surveys, post-run metrics, and memory persistence.
When to Use This Pattern
Use when:
- Coordinating continuous improvement across multiple concurrent agent sessions.
- Evaluating and improving multiple skills, workflows, or templates in parallel.
- You need every cycle to generate measurable accuracy gains and persistent memory.
Do NOT use for:
- Single-session procedural tasks (use
os-eval-runner directly).
- Signal-only coordination with no evaluation, survey, or memory steps.
Key Invariants
- No-Rollback Rule: Never manually roll back changes during a cycle unless
evaluate.py registers an explicit accuracy regression.
- Eval Gate Mandatory: Every modification must pass the independent evaluation gate (
evaluate.py exit code 0). No manual bypasses.
- NEVER STOP Discipline: Do not abort a running loop due to minor/moderate errors. Complete the loop close checklist and log unresolved issues as Map Debt.
- Outer Loop Ownership: The outer loop owns session lifecycle. Inner loop tasks (
os-eval-runner) must not prematurely close a session without running Stage 4 (memory promotion and survey collection).
Stage Pointers & Reference Protocols
The execution details are split across modular references:
- Stage 0: Setup and Orientation — Pre-flight reads, registry, and packet design.
- Stage 1: INNER_AGENT Execution — Strategy execution, friction logging, and local scoring.
- Stage 2: PEER_AGENT Verification — Independent evaluation run and verdict formulation.
- Stage 3: Decision Logic — KEEP/DISCARD actions and correction packets.
- Stage 4: Loop Close Checklist — Surveys, ledger updates, memory promotion, and retrospectives.
- Orchestrator Meta-Survey — Meta-evaluation of loop coordination patterns.
- Lab Limits — Hard caps on iterations, eval sets, and critic invocations per run.
Smoke Test
- Verify Event Registry: Run
os-init or start a test loop. Assert that context/events.jsonl registers start events correctly.
- Execute Scorer: Run
python3 ./scripts/evaluate.py --skill skills/todo-check/ on a dummy check to verify that exit codes map correctly (0 for KEEP, 1 for DISCARD, 2 for path error).
- Friction Event Test: Propose a manual edit, emit a mock
friction event, resolve it with friction.resolved, and verify the metrics engine logs the resolution gate pass.
Gotchas
- Conflation of Loops: Conflating the inner target skill loop with the outer OS-improvement loop. Outer loop changes the OS workflows; inner loop changes target skills.
- Orphaned Sessions: Completing inner loop tasks but failing to run memory promotion and survey curation. Ephemeral findings are lost.
- Directory Symlinks: Creating directory-level symlinks from skills to shared roots. Use file-level symlinks only — directory symlinks fail on cross-platform checkouts. Shared resources must be hard copies or individual file symlinks, never directory-level links.
HANDOFF_BLOCK Template
Every loop execution that completes a cycle must output this block in its handoff:
## HANDOFF_BLOCK
- **Cycle ID**: cycle-YYYYMMDD-HHMMSS
- **Target Skill**: [path/to/target]
- **Verdict**: KEEP / DISCARD
- **Score (Before -> After)**: [0.XX -> 0.YY]
- **Friction Events**: [N encountered / N resolved]
- **Outstanding Map Debt**: [list links or IDs]
- **Recommended Next Step**: [next hypothesis to test]
1---2name: os-improvement-loop3description: Pattern 5: Concurrent Event-Driven Multi-Agent Loop. Coordinates multiple Claude sessions as OS threads sharing a common event bus and memory address space. Every loop cycle is a full improvement cycle: execute, eval against benchmark (KEEP/DISCARD), emit friction events, and close with surveys, metrics, memory persistence, and Triple-Loop triggers.4---56# Concurrent Agent Loop78Treats concurrent sessions as OS threads sharing a common event bus and memory address space. Every cycle includes execution, independent peer evaluation, friction tracking, self-assessment surveys, post-run metrics, and memory persistence.910---1112## When to Use This Pattern1314Use when:15- Coordinating continuous improvement across multiple concurrent agent sessions.16- Evaluating and improving multiple skills, workflows, or templates in parallel.17- You need every cycle to generate measurable accuracy gains and persistent memory.1819Do NOT use for:20- Single-session procedural tasks (use `os-eval-runner` directly).21- Signal-only coordination with no evaluation, survey, or memory steps.2223---2425## Key Invariants2627- **No-Rollback Rule**: Never manually roll back changes during a cycle unless `evaluate.py` registers an explicit accuracy regression.28- **Eval Gate Mandatory**: Every modification must pass the independent evaluation gate (`evaluate.py` exit code 0). No manual bypasses.29- **NEVER STOP Discipline**: Do not abort a running loop due to minor/moderate errors. Complete the loop close checklist and log unresolved issues as Map Debt.30- **Outer Loop Ownership**: The outer loop owns session lifecycle. Inner loop tasks (`os-eval-runner`) must not prematurely close a session without running Stage 4 (memory promotion and survey collection).3132---3334## Stage Pointers & Reference Protocols3536The execution details are split across modular references:37- [Stage 0: Setup and Orientation](references/stage-0-orientation.md) — Pre-flight reads, registry, and packet design.38- [Stage 1: INNER_AGENT Execution](references/stage-1-execution.md) — Strategy execution, friction logging, and local scoring.39- [Stage 2: PEER_AGENT Verification](references/stage-2-verification.md) — Independent evaluation run and verdict formulation.40- [Stage 3: Decision Logic](references/stage-3-decision.md) — KEEP/DISCARD actions and correction packets.41- [Stage 4: Loop Close Checklist](references/stage-4-close.md) — Surveys, ledger updates, memory promotion, and retrospectives.42- [Orchestrator Meta-Survey](references/orchestrator-meta-survey.md) — Meta-evaluation of loop coordination patterns.43- [Lab Limits](references/lab-limits.md) — Hard caps on iterations, eval sets, and critic invocations per run.4445---4647## Smoke Test48491. **Verify Event Registry**: Run `os-init` or start a test loop. Assert that `context/events.jsonl` registers start events correctly.502. **Execute Scorer**: Run `python3 ./scripts/evaluate.py --skill skills/todo-check/` on a dummy check to verify that exit codes map correctly (0 for KEEP, 1 for DISCARD, 2 for path error).513. **Friction Event Test**: Propose a manual edit, emit a mock `friction` event, resolve it with `friction.resolved`, and verify the metrics engine logs the resolution gate pass.5253---5455## Gotchas5657- **Conflation of Loops**: Conflating the inner target skill loop with the outer OS-improvement loop. Outer loop changes the OS workflows; inner loop changes target skills.58- **Orphaned Sessions**: Completing inner loop tasks but failing to run memory promotion and survey curation. Ephemeral findings are lost.59- **Directory Symlinks**: Creating directory-level symlinks from skills to shared roots. Use file-level symlinks only — directory symlinks fail on cross-platform checkouts. Shared resources must be hard copies or individual file symlinks, never directory-level links.6061---6263## HANDOFF_BLOCK Template6465Every loop execution that completes a cycle must output this block in its handoff:6667```markdown68## HANDOFF_BLOCK69- **Cycle ID**: cycle-YYYYMMDD-HHMMSS70- **Target Skill**: [path/to/target]71- **Verdict**: KEEP / DISCARD72- **Score (Before -> After)**: [0.XX -> 0.YY]73- **Friction Events**: [N encountered / N resolved]74- **Outstanding Map Debt**: [list links or IDs]75- **Recommended Next Step**: [next hypothesis to test]76```