\n\nTL;DR: Some COG skills are not one-shot prompts. They are loops: act, observe, verify, decide whether to continue. This skill is the shared vocabulary those skills use. The iron rule: trust deterministic checks, never the agent's own \"looks done\" self-report. Every loop must declare its verifier, its stopping conditions, and which pattern it follows.
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This is a reference and design aid, not a content-generating workflow. Skills that loop (daily-brief, knowledge-consolidation, url-dump, weekly-checkin, and research/triage skills like auto-research and scout) link here instead of restating the rules. Invoke it directly when you are building or fixing an iterative skill.
\nA chain runs fixed steps: A then B then C. A loop is dynamic: the agent takes an action, reads real feedback (a fetched page, a date stamp, a file count), reasons about it, and repeats until a goal is met or a stop condition fires. Most knowledge-work that \"keeps going until good enough\" is a loop, and COG benefits from naming the loop explicitly rather than hoping a single prompt nails it.
\n ┌──────────────────────────────────────────────┐\n │ 1. Gather pull context (vault + sources) │\n │ 2. Act one step: search / fetch / scan │\n │ 3. Observe read the real result │\n │ 4. Verify run the deterministic check │\n │ 5. Update write progress to a vault file │\n │ 6. Decide continue? → loop │\n │ stop? → finish + report │\n └──────────────────────────────────────────────┘\nStep 4 is the load-bearing one. A loop without a verifier is just a chain that repeats.
\nA robust loop needs several exits so it always halts:
\n| Exit | \nWhat it is | \nExample | \n
|---|---|---|
| Deterministic verifier | \nA mechanical pass/fail that confirms the goal | \n\"Publication date is within 7 days\" | \n
| Hard iteration cap | \nMax passes, no matter what | \n\"Stop after 5 searches per topic\" | \n
| Budget guard | \nMax time / tool calls / tokens | \n\"Stop after 20 fetches total\" | \n
| No-progress detection | \nRecent passes changed nothing | \n\"2 searches in a row found nothing new\" | \n
| Human escalation | \nHand a stuck loop back to the user | \n\"Asked twice, still unclear: ask the user\" | \n
Pick the verifier plus at least one safety exit (cap or budget) for every loop. No-progress detection is what stops the quiet infinite loops that a cap alone misses.
\nCOG is verification-first: no hallucinations, sources required. Inside a loop that means:
\nLong loops fill the window with old tool output and start to drift (\"context rot\"). Counter it:
\nagent_mode: team, give each worker only the slice it needs and take back only its conclusion, so one subtask runs in a clean window. Never paste one worker's raw output into the next worker's prompt.| Pattern | \nShape | \nWhere COG uses it | \n
|---|---|---|
| Act-observe (ReAct) | \nreason → act → observe → repeat | \nbase of every COG loop | \n
| Reflect-retry (Reflexion) | \non failure, write the lesson, retry differently | \nurl-dump / scout fetch retries, daily-brief re-search | \n
| Plan-execute-verify | \nplan steps, run them, verify each | \nknowledge-consolidation passes | \n
| Evaluator-optimizer | \ngenerate, score against criteria, repeat until it passes | \ndaily-brief item verify, url-dump quality gate | \n
| Orchestrator-workers | \nsplit into subtasks, run in fresh windows, synthesize | \nteam-mode scans, auto-research threads, team-brief | \n
| Loop-until-dry | \nkeep going until K passes in a row surface nothing new | \nknowledge-consolidation theme extraction | \n
| Human-in-the-loop | \nescalate or ask when the loop is stuck or the call is the user's | \nweekly-checkin reflection, onboarding | \n
| Failure | \nFix | \n
|---|---|
| Context overflow / drift | \ncompact, prune, externalize to vault, isolate sub-agents | \n
| Silent infinite loop | \nno-progress detection plus a hard cap | \n
| Hallucinated success | \ntrust the deterministic verifier, never self-report | \n
| Compounding errors | \nverify early and every pass, not only at the end | \n
| Cost blowup | \nbudget guard, and stop at \"good enough\", not \"perfect\" | \n
| Goal drift | \nkeep the goal and stop conditions written at the top of the loop's state | \n
A skill's ## Loop Engineering section should be short and concrete. It names:
It does not restate this skill. It points here.
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