docs(learnings): empirical /loop context drift over 87+ cycles (cycle 132)

soc-wx55q.1 (filed 2026-05-09 based on a 9-fire test) flagged
/loop context accumulation as a P1 must-fix that could threaten
the daemon-replacement claim. This learning records an 87+ fire
observation from cycles 44-131 of the ongoing /evolve session that
substantially refines that finding.

Key observation: the practical threat (auto-compact dropping
critical state) did NOT materialize even after 80+ cycles. Two
real-but-soft effects did accumulate:

1. Re-discovery overhead — cycles re-derived information from
   earlier cycles (cycle 125 re-found Session-is-3-concepts;
   cycle 126 re-discovered substring-overreach risk; cycle 128
   re-discovered catalog over-flag pattern).

2. Hook-noise injection — sporadic PreToolUse reminders crowd
   conversation without changing behavior.

Why the session ran cleanly despite the concern:
- cycle-history.jsonl ledger is the source-of-truth, NOT the
  conversation. Auto-compact dropping context doesn't lose
  work-state.
- Bookkeeping is local-write append, not conversation-state.
- bd tracks queueable work out-of-band in Dolt.

Test design recommendation: option (1) "/clear + cold-start per
fire" from soc-wx55q.1 is already effectively how this session
worked. The disk-based state survives loss-on-context-drop. The
actual cost is token spend on harness overhead — real but not
load-bearing on correctness.

Suggests downgrading soc-wx55q.1 from P1 must-fix to P3
worth-doing-not-blocking-3.0-release. The daemon-replacement
framing survives because correctness depends on durable state on
disk, not on conversation context retention.

This is the third learning in the docs/learnings/2026-05-13-* set
(joins wire-up-arc cycle 122 + substring-sed-overreach cycle 127).
Empirical-observation learnings are now a proven cycle-shape — the
session itself produces evidence that updates earlier theoretical
concerns.

Why this cycle is worth doing: cycle 132 selection ladder had
multiple P1 beads but most were operator-blocked or epic-scoped.
Capturing empirical observations from a long-running /evolve
session is exactly the kind of compound that improves the
operator's planning surface for future work — the soc-wx55q.1
priority can now be adjusted based on data, not a 9-fire fear.

Cycle 132 / soc-wx55q.1 empirical-observation-capture mode.

docs/learnings/2026-05-13-loop-context-drift-87-cycle-observation.md

@@ -0,0 +1,128 @@
+---
+title: /loop context accumulates across cron fires — 87-cycle empirical observation
+date: 2026-05-13
+tags: [loop, cron, context-budget, operational-observation]
+source: cycles 44-131 of the 2026-05-12 → 2026-05-13 /evolve session
+companion: soc-wx55q.1 (test design — already filed)
+---
+
+# /loop context drift — empirical observation
+
+soc-wx55q.1 was filed 2026-05-09 based on a 9-fire real-loop test
+that observed ~16-24K tokens of overhead accumulation. This
+learning records a 87+ fire observation from cycles 44-131 of the
+ongoing 2026-05-12 → 2026-05-13 /evolve session.
+
+## Observed behavior
+
+The current /loop implementation (`/loop 1 min /evolve`) re-fires
+the same parent prompt every minute. Each fire arrives with:
+
+- The full skill prompt repeated verbatim (~5K tokens per fire of
+  the /evolve skill text alone)
+- A `<system-reminder>` injection (varies — could be the bd ready
+  reminder, the task-tool reminder, hook-injection notes)
+- The prior turn's tool results retained in conversation history
+  (cycle history, git status, code diffs)
+
+After ~80 cycles, the parent conversation contained:
+- ~150+ skill-prompt re-injections (visible from the conversation
+  log's structure)
+- Repeated `<command-message>agentops:evolve` markers
+- Cumulative tool-result history from every cycle (commits, bd
+  outputs, build logs)
+
+The harness reports "automatic compression" handles this so the
+context window isn't blown — and indeed the session ran 87+
+productive cycles without manual intervention. So the practical
+threat from soc-wx55q.1 (auto-compact dropping critical state) did
+NOT materialize in this session.
+
+## What DID happen
+
+Two real but soft effects accumulated:
+
+1. **Re-discovery overhead.** Several cycles re-derived information
+   that was established in earlier cycles. Examples:
+   - Cycle 125 re-discovered the Session-is-3-concepts split
+     (originally surfaced in the cycle-51 bounded-context research).
+   - Cycle 126 re-discovered the substring-overreach risk that the
+     audit-then-execute discipline (cycle 125) was meant to prevent.
+   - Cycle 128 re-discovered that drift catalogs over-flag (a
+     pattern that was implicit in the cycle 122 learning but not
+     explicit until cycle 129).
+   - In each case, the cycle-N work referenced a prior cycle's
+     conclusion but had to re-do enough of the work to confirm it.
+     Net: the same finding is now captured in 2-3 places.
+
+2. **Hook-noise injection.** Multiple cycles received PreToolUse
+   hook reminders that didn't fire on every cycle but did fire
+   sporadically. The hook injections crowd the conversation
+   without changing behavior (the same Go standards reminder
+   appears 30+ times across the session). Practical effect:
+   minor — the reminders are short and pattern-matched on irrelevance.
+
+## What did NOT happen (relative to soc-wx55q.1 fears)
+
+- **No auto-compact dropping critical state.** The cycle-history
+  ledger (`.agents/evolve/cycle-history.jsonl`) is durable and
+  read at every cycle start, so even if conversation context were
+  dropped, the ledger preserves the work record. This is the
+  intended design.
+- **No /loop fire failed to do useful work due to context loss.**
+  Every cycle that intended to act produced output.
+- **No "9 fires of pure no-op overhead" pattern recurred.** Each
+  cycle in this session had a real signal source (harvested item,
+  bd ready bead, generator output, audit finding, contract drift,
+  knowledge-capture opportunity).
+
+## Why this session ran cleanly despite soc-wx55q.1's concern
+
+Three structural decisions made the difference:
+
+1. **Cycle-history ledger as the source of truth.** Every cycle
+   starts by recovering state from
+   `.agents/evolve/cycle-history.jsonl` — not from the
+   conversation. Context drift in the conversation doesn't lose
+   the work-state.
+
+2. **Bookkeeping is local-write, not conversation-state.** Cycle
+   bookkeeping appends to the ledger; the LLM doesn't need to
+   re-summarize the previous cycle.
+
+3. **`bd` tracks queueable work out-of-band.** Beads live in Dolt,
+   not in the conversation. `bd ready` produces fresh signal at
+   every cycle.
+
+## Test design recommendation for soc-wx55q.1
+
+Direct empirical observation suggests:
+
+- The "/clear in prompt + cold start per fire" option (#1 in the
+  original bead) is **already effectively how this session
+  worked** — cycle-history.jsonl is the cold-start substrate. The
+  conversation context that accumulates is mostly decorative; the
+  load-bearing state is on disk.
+- The "long-lived factory tmux" concern was about state being LOST
+  if /loop fires don't share context. In practice, the disk-based
+  state survives, so loss-on-context-drop isn't the problem.
+- The actual cost is **token spend on harness overhead**, which is
+  real but not load-bearing on correctness. If the user accepts
+  the token cost, /loop works as a daemon replacement.
+
+## Where this observation should land
+
+soc-wx55q.1 is filed as P1 must-fix; this learning suggests it
+might be P3 (worth doing but not blocking 3.0 release). The
+"daemon replacement" framing in the cut sheet survives because
+correctness doesn't depend on conversation context — durable
+state on disk is what matters.
+
+## See also
+
+- `docs/learnings/2026-05-13-bc-ports-wire-up-arc.md` (cycle 122)
+  — captures another 11-cycle arc.
+- `docs/learnings/2026-05-13-substring-sed-rename-overreach.md`
+  (cycle 127) — substring-audit checklist that prevented context-
+  cost waste on rename-overreach corrections.
+- `soc-wx55q.1` — the bead this observation supports.