diff --git a/.claude/rules/agent-worktree-hygiene-never-hold-main-never-step-on-operator-cleanup-on-pr-merge.md b/.claude/rules/agent-worktree-hygiene-never-hold-main-never-step-on-operator-cleanup-on-pr-merge.md
index a8d117889d..1a6a19d357 100644
--- a/.claude/rules/agent-worktree-hygiene-never-hold-main-never-step-on-operator-cleanup-on-pr-merge.md
+++ b/.claude/rules/agent-worktree-hygiene-never-hold-main-never-step-on-operator-cleanup-on-pr-merge.md
@@ -169,18 +169,18 @@ operator MAY have `main` checked out in their own primary, but agents
 must not.
 
 ```bash
-# Should print no lines. If any line prints, an agent worktree is
-# holding [main] and is the blocker for operator git operations.
+# Prints OK on success. If a worktree line prints, an agent worktree
+# is holding [main] and is the blocker for operator git operations.
 git worktree list | awk '/\[main\]/ { path=$1 } END { exit 0 }' \
   && git worktree list | grep -E "\[main\]" \
   | grep -E "/private/tmp/zeta-|/tmp/zeta-" || echo "OK: no agent holds [main]"
 ```
 
-Expected result: no agent worktree holds `[main]`. No output is OK when the
-operator's primary checkout is not currently on `main`; a single operator
-primary line is also OK when the operator intentionally has `main` checked out.
-Any `/private/tmp/zeta-*`, `/tmp/zeta-*`, or per-agent worktree line holding
-`[main]` is a violation to fix.
+Expected result: `OK: no agent holds [main]`, or equivalently no
+agent-worktree match if the final echo is omitted. A single operator
+primary line is OK when the operator intentionally has `main` checked
+out. Any `/private/tmp/zeta-*`, `/tmp/zeta-*`, or per-agent worktree
+line holding `[main]` is a violation to fix.
 
 ## Substrate-honest framing
 
@@ -206,11 +206,10 @@ worktrees in the operator's primary checkout subdir (peer-agent
 prefix; from past work), and 1 stale `/private/tmp/zeta-<peer-loop>-2`
 worktree holding `[main]` at stale SHA.
 
-The `[main]`-holding worktree was THE blocker for operator's
-`git checkout main` in primary checkout. Operator explicit: *"i'm
-stuck (max)... fatal: 'main' is already used by worktree at
-'/private/tmp/zeta-<peer-loop>-2'... nope we need to fix this mess
-yall always stepping on each other and me constantly"*.
+The `[main]`-holding worktree was THE blocker for the operator's
+`git checkout main` in the primary checkout. The exact operator quote
+is preserved on the B-0750 backlog/history surface; this current-state
+rule keeps the operational lesson in role-reference form.
 
 Mass-cleanup (37 worktrees removed) plus this rule landing prevents
 recurrence. Future agent surfaces inherit the discipline at cold-boot.
diff --git a/docs/BACKLOG.md b/docs/BACKLOG.md
index 0d3d9379d6..f1264563db 100644
--- a/docs/BACKLOG.md
+++ b/docs/BACKLOG.md
@@ -697,7 +697,7 @@ are closed (status: closed in frontmatter)._
 - [ ] **[B-0737](backlog/P2/B-0737-zflash-touch-id-pam-plus-short-challenge-format-plus-iso-auto-discovery-i-execute-you-fingerprint-aaron-2026-05-25.md)** zflash — "I execute, you fingerprint" — Touch ID PAM as the irreversible-action consent gate + short `yes <4-hex>` challenge + ISO auto-discovery (~14 keystrokes total for human; agent-driven path uses same Touch ID floor)
 - [ ] **[B-0742](backlog/P2/B-0742-reference-k8s-local-stack-as-aces-distributable-poc-hats-as-negotiated-fork-structure-on-top-deterministic-declarative-gitops-ai-native-human-native-aaron-2026-05-25.md)** Reference k8s local stack in Zeta as Ace's distributable PoC — hats become the negotiated fork structure ON TOP of the reference stack — anyone can use it, anyone can negotiate back hats + new cluster primitives + new charts via the B-0741 ontology negotiation protocol — Ace's PoC of reliable AI control over all package managers in a deterministic + declarative / desired-state / GitOps-friendly + AI-native + human-native way
 - [ ] **[B-0748](backlog/P2/B-0748-kro-crossplane-koreo-kubevela-carvel-ack-kcc-aso-spectrum-evaluation-for-zeta-reference-stack-machine-state-fork-state-aaron-2026-05-25.md)** kro + Crossplane + Koreo + KubeVela + Carvel + ACK/KCC/ASO spectrum evaluation for Zeta — adopt where it composes (Aaron 2026-05-25 'kro yes' endorsement + 'we need lots of research in this area and backlog' direction); evaluate adoption against B-0742 reference stack + B-0747 machine-state reconciler + B-0741 cross-cluster federation + downstream-fork story
-- [ ] **[B-0750](backlog/P2/B-0750-agent-worktree-hygiene-rule-landing-plus-mechanization-target-cleanup-tooling-plus-worktree-pool-primitive-aaron-2026-05-25.md)** Agent worktree hygiene — rule-landing + substrate-engineering mechanization target — periodic cleanup tooling + worktree-pool handoff to B-0558/B-0751; operator's 'we need to fix this mess yall always stepping on each other and me constantly' anchor 2026-05-25 (37 worktrees mass-cleaned + rule landed simultaneously)
+- [ ] **[B-0750](backlog/P2/B-0750-agent-worktree-hygiene-rule-landing-plus-mechanization-target-cleanup-tooling-plus-worktree-pool-primitive-aaron-2026-05-25.md)** Agent worktree hygiene — rule-landing + substrate-engineering mechanization target — periodic cleanup tooling + worktree-pool handoff to B-0558 plus PR #5019 clone-architecture sibling; operator's 'we need to fix this mess yall always stepping on each other and me constantly' anchor 2026-05-25 (37 worktrees mass-cleaned + rule landed simultaneously)
 - [ ] **[B-0752](backlog/P2/B-0752-fighting-past-self-vs-peer-distinguisher-rule-landing-plus-identity-tagging-mechanization-aaron-vera-2026-05-25.md)** Fighting past-self vs peer-agent — distinguisher rule landing + identity-tagging mechanization scope (Aaron 2026-05-25 'you don't do like vera and just leave it unfixed cause you assume it's someone elses issues')
 - [ ] **[B-0755](backlog/P2/B-0755-cluster-role-taxonomy-expansion-control-plane-gpu-worker-cpu-worker-storage-all-in-one-aaron-2026-05-25.md)** Cluster role taxonomy expansion — control-plane-gpu, worker-cpu, worker-storage, all-in-one fused host configs
 - [ ] **[B-0759](backlog/P2/B-0759-cluster-install-ux-audit-against-first-time-cli-user-persona-easier-than-proxmox-3-node-production-ready-aaron-2026-05-25.md)** Cluster-install UX audit against first-time-CLI-user persona — "easier than Proxmox" bar + 3-node production-ready inflection
diff --git a/docs/backlog/P2/B-0750-agent-worktree-hygiene-rule-landing-plus-mechanization-target-cleanup-tooling-plus-worktree-pool-primitive-aaron-2026-05-25.md b/docs/backlog/P2/B-0750-agent-worktree-hygiene-rule-landing-plus-mechanization-target-cleanup-tooling-plus-worktree-pool-primitive-aaron-2026-05-25.md
index 76de661ec6..fa831ee8c8 100644
--- a/docs/backlog/P2/B-0750-agent-worktree-hygiene-rule-landing-plus-mechanization-target-cleanup-tooling-plus-worktree-pool-primitive-aaron-2026-05-25.md
+++ b/docs/backlog/P2/B-0750-agent-worktree-hygiene-rule-landing-plus-mechanization-target-cleanup-tooling-plus-worktree-pool-primitive-aaron-2026-05-25.md
@@ -4,14 +4,13 @@ priority: P2
 status: open
 created: 2026-05-25
 last_updated: 2026-05-26
-title: Agent worktree hygiene — rule-landing + substrate-engineering mechanization target — periodic cleanup tooling + worktree-pool handoff to B-0558/B-0751; operator's 'we need to fix this mess yall always stepping on each other and me constantly' anchor 2026-05-25 (37 worktrees mass-cleaned + rule landed simultaneously)
+title: Agent worktree hygiene — rule-landing + substrate-engineering mechanization target — periodic cleanup tooling + worktree-pool handoff to B-0558 plus PR #5019 clone-architecture sibling; operator's 'we need to fix this mess yall always stepping on each other and me constantly' anchor 2026-05-25 (37 worktrees mass-cleaned + rule landed simultaneously)
 domain: ops-tooling
 ferried_by: aaron
 owners: [aaron]
 composes_with:
   - B-0530
   - B-0558
-  - B-0751
 related_substrate:
   - .claude/rules/agent-worktree-hygiene-never-hold-main-never-step-on-operator-cleanup-on-pr-merge.md
   - .claude/rules/claim-acquire-before-worktree-work.md
@@ -22,7 +21,7 @@ tags: [agent-worktree-hygiene, multi-agent-worktree-contention, operator-unblock
 
 ## Carved blade
 
-> Operator 2026-05-25: *"i'm stuck (max) ➜ Zeta git:(lior-archive-prs-2026-05-26) ✗ git checkout main → fatal: 'main' is already used by worktree at '/private/tmp/zeta-riven-loop-2'... nope we need to fix this mess yall always stepping on each other and me constantly."* The proximate cause was 37 agent worktrees from one substrate-cascade day, including one peer-agent worktree holding `[main]` at stale SHA. Mass-cleanup unblocked + the agent-worktree-hygiene rule landed simultaneously, but the substrate-engineering target is mechanization: periodic cleanup tooling (auto-prune post-PR-merge) plus an ownership architecture handoff. The older worktree-pool primitive remains in B-0558; B-0751 (PR #5019, per-agent isolated clones) supersedes the pool as the preferred architecture for future agent isolation. Until mechanization lands, agent-side compliance with the rule operates the discipline.
+> Operator 2026-05-25: *"i'm stuck (max) ➜ Zeta git:(lior-archive-prs-2026-05-26) ✗ git checkout main → fatal: 'main' is already used by worktree at '/private/tmp/zeta-riven-loop-2'... nope we need to fix this mess yall always stepping on each other and me constantly."* The proximate cause was 37 agent worktrees from one substrate-cascade day, including one peer-agent worktree holding `[main]` at stale SHA. Mass-cleanup unblocked + the agent-worktree-hygiene rule landed simultaneously, but the substrate-engineering target is mechanization: periodic cleanup tooling (auto-prune post-PR-merge) plus an ownership architecture handoff. The older worktree-pool primitive remains in B-0558; the per-agent isolated-clones architecture in PR #5019 supersedes the pool as the preferred architecture for future agent isolation, but is not listed in `composes_with` until its backlog row is main-visible. Until mechanization lands, agent-side compliance with the rule operates the discipline.
 
 ## Origin
 
@@ -58,19 +57,21 @@ Plus specific cleanup commands (audit / per-worktree clean check / mass-remove s
 - Composes with B-0530 cron-sentinel mutex semantics
 - Acceptance: tool exists; runs successfully; at least one cycle of auto-cleanup demonstrated
 
-### Scope item 2 — Worktree-pool primitive handoff (B-0558 + B-0751)
+### Scope item 2 — Worktree-pool primitive handoff (B-0558 + PR #5019)
 
 - B-0558 already owns the original worktree-pool primitive
   (pre-allocated sideticks per Otto identity; PR #3894 archive:
   `docs/pr-discussions/PR-3894-backlog-b-0558-worktree-pool-primitive-re-land-of-3817-backl.md`)
-- B-0751 (PR #5019, per-agent isolated clones) supersedes a shared
-  worktree pool as the preferred architecture for per-agent isolation
+- PR #5019 (per-agent isolated clones architecture) supersedes a
+  shared worktree pool as the preferred architecture for per-agent
+  isolation. It is referenced by PR URL/number here, not frontmatter
+  `composes_with`, because its backlog row is not yet main-visible.
 - This B-0750 row therefore tracks only the hygiene delta: agents must
   not hold `main`, must not use operator paths, and must clean up owned
   worktrees after merge/abandon
 - Any future pool work should compose through B-0558 or be explicitly
-  deferred under B-0751 clone architecture; B-0750 should not grow a
-  second pool implementation track
+  deferred under the PR #5019 clone architecture; B-0750 should not
+  grow a second pool implementation track
 
 ### Scope item 3 — Post-PR-merge auto-cleanup hook
 
@@ -98,7 +99,7 @@ Plus specific cleanup commands (audit / per-worktree clean check / mass-remove s
 
 - **Cross-machine agent worktree coordination** — if agents run on different machines + share git via push/pull, the worktrees are per-machine; cross-machine cleanup is future scope
 - **New worktree-pool implementation** — B-0558 owns the historical
-  pool primitive; B-0751 per-agent clones supersede the shared-pool
+  pool primitive; PR #5019 per-agent clones supersede the shared-pool
   approach for new architecture work
 - **Operator's own worktree creation** — operator can always create worktrees anywhere; rule applies to agents only
 - **Automated branch deletion** — separate scope; depends on PR-mergedness + downstream dependencies (per B-0741 fork interop)
@@ -117,8 +118,9 @@ Plus specific cleanup commands (audit / per-worktree clean check / mass-remove s
 - **B-0530** (cron-sentinel mutex; existing partial substrate) — same problem class at runtime scope; this row's cleanup discipline composes
 - **B-0558** (worktree-pool primitive per Otto identity) — owns the
   historical pool design; B-0750 narrows to hygiene + cleanup delta
-- **B-0751** (per-agent isolated clones; PR #5019) — supersedes shared
-  pool direction as the preferred isolation architecture
+- **PR #5019** (per-agent isolated clones) — supersedes shared pool
+  direction as the preferred isolation architecture; intentionally not
+  in `composes_with` until its B-row exists on main
 - **B-0732** (leverage-class safety substrate) — Layer 1 provenance chain captures cleanup events
 - **B-0737** (zflash empirical anchor) — operator was trying to use zflash when the worktree mess blocked them; concrete pain
 - **B-0746** (GitHub force-push lesson) — related sibling failure mode at GitHub-state scope