feat(bg): B-0501 slice 5a — assignment history dedup cooldown

[AceHack]

Implements backlog row B-0501 (Slice 5a of the B-0441 notifier). We now properly check assignment history to avoid re-assigning the same row multiple times within a configurable cooldown period (default 30 mins). It uses atomic renames via /tmp/zeta-bus for concurrent-safe history tracking.

[Copilot]

Pull request overview

Adds an assignment-history dedup cooldown to the backlog-ready notifier (B-0501, slice 5a of B-0441). On each poll the notifier now first gates publishing on the target agent's queue being empty, then filters ready rows against a persisted history file, and after publishing writes back a pruned history via temp-file + rename.

Changes:

• Extend NotifierConfig/PollResult with targetAgent, historyFile, cooldownMin, queueBusy, and skippedDueToCooldown, plus CLI flags --target-agent, --history-file, --cooldown-min.
• Add readHistoryFile/writeHistoryFile adapters (real impl uses mkdirSync + temp-file + renameSync) and wire pollOnce to check cooldown, skip duplicates, and prune+persist on publish.
• Add tests covering empty history, in-cooldown skip, post-cooldown re-assign, mixed expired/active entries, pruning on write, and the new parseArgs flags.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
tools/bg/backlog-ready-notifier.ts	New config/result fields, history-file adapters, cooldown filter + prune-and-write, expanded CLI parsing, queue-busy short-circuit.
tools/bg/backlog-ready-notifier.test.ts	Extended fake adapters with history hooks; new test groups for queue-busy interaction, cooldown dedup behaviour, and new CLI flags.

Comments suppressed due to low confidence (1)

tools/bg/backlog-ready-notifier.ts:225

• The temp filename uses ${path}.tmp.${Date.now()} for uniqueness, but Date.now() has millisecond resolution and concurrent writes within the same millisecond will collide and corrupt each other's temp file before rename. Consider appending process.pid and/or a random suffix (e.g. crypto.randomUUID()) to make collisions astronomically unlikely.

    const tmp = `${path}.tmp.${Date.now()}`;

[chatgpt-codex-connector]

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Reviewed commit: f0ba90a599

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[AceHack]

Vera read-only review-state triage from the main-backed control clone, 2026-05-15T21:59Z. I did not patch this branch because it is feat/b0501-history-dedup, auto-merge is armed by Aaron, and I do not see a Vera co-claim for the tools/bg/backlog-ready-notifier.ts path set.

Current state I see:

• PR is DIRTY against main, so it needs a rebase/update before auto-merge can land.
• Four unresolved review threads remain, all in tools/bg/backlog-ready-notifier.ts:
  • line 230 / 225: PR wording says concurrent-safe history tracking, but the implementation only makes file replacement atomic; the read-modify-write window is still last-writer-wins. Either narrow the claim to atomic replacement / single-process dedup or add real locking/CAS.
  • line 36: targetAgent accepts any string, unlike fromAgent / toAgent; a typo can silently bypass queue-busy gating. Validate against known agent IDs or warn/fail on unknown values.
  • line 319: readHistoryFile accepts any JSON shape, then pollOnce assumes entries is an array and calls .filter; malformed or old history can crash the loop. Guard schema and fall back safely.
  • line 355: cooldown history is reconstructed by indexing publishedEnvelopeIds into toAssign; skipped invalid-priority rows can record the wrong rowId, leaving the actually published row outside cooldown.

Safe owner-side next step: update from main, patch those four review findings, and rerun the focused background notifier tests / typecheck before trusting auto-merge.

No contested-root writes and no overlapping branch edits from Vera.

[chatgpt-codex-connector]

💡 Codex Review

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Reviewed commit: b2033b47c1

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[chatgpt-codex-connector]

Catch history write failures before returning poll result

A filesystem error while persisting cooldown history will currently throw out of pollOnce, because adapters.writeHistoryFile(...) is not guarded by a try/catch. In daemon mode this can terminate the notifier loop on transient conditions (permission issues, full disk, path problems), even though publish failures are explicitly handled as non-fatal. This turns optional dedup bookkeeping into a single-point process crash.

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[chatgpt-codex-connector]

Avoid hard-coding otto as the queue target default

The new queue gate defaults targetAgent to "otto", so runs that change assignee/sender (for example via --to/--agent) but omit --target-agent will still evaluate Otto’s queue state. That can cause assignments to be skipped or sent based on the wrong person’s activity, violating the queue-empty gating for non-Otto workflows.

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