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+---
+pr_number: 3546
+title: "shard(tick): 1820Z \u2014 B-0533 Slice A POC merged; peer-Otto worktree-contention rescue"
+author: "AceHack"
+state: "MERGED"
+created_at: "2026-05-15T18:26:46Z"
+merged_at: "2026-05-15T18:29:17Z"
+closed_at: "2026-05-15T18:29:17Z"
+head_ref: "shard/tick-1820z-otto-cli-2026-05-15"
+base_ref: "main"
+archived_at: "2026-05-15T18:33:24Z"
+archive_tool: "tools/pr-preservation/archive-pr.ts"
+---
+
+# PR #3546: shard(tick): 1820Z — B-0533 Slice A POC merged; peer-Otto worktree-contention rescue
+
+## PR description
+
+## Summary
+
+Tick 1820Z. PR #3544 (B-0533 Slice A POC) merged this tick. Caught + rescued peer-Otto worktree-contention (concurrent Otto-CLI committed cfbc2c5 to borrowed sidetick worktree mid-tick; preserved on \`peer-otto-b0534-rescue-cfbc2c5\` branch before my reset).
+
+## Test plan
+
+- [x] Shard at canonical path
+- [ ] CI green
+- [ ] Auto-merge arms
+
+🤖 Generated with [Claude Code](https://claude.com/claude-code)
+
+## Reviews
+
+### COMMENTED — @copilot-pull-request-reviewer (2026-05-15T18:27:50Z)
+
+## Pull request overview
+
+This PR adds a tick log under `docs/hygiene-history/ticks/` documenting the 1820Z tick: the merge of B-0533 Slice A POC (PR #3544) and the rescue of a concurrent Otto-CLI commit found on a borrowed worktree.
+
+**Changes:**
+- New tick log file recording merged PRs, refined dead-xref scan, and peer-Otto worktree-contention rescue.
+
+## General comments
+
+### @chatgpt-codex-connector (2026-05-15T18:26:50Z)
+
+You have reached your Codex usage limits for code reviews. You can see your limits in the [Codex usage dashboard](https://chatgpt.com/codex/cloud/settings/usage).