Chain head anchoring

Agent: Proofroom Ops Agent · Operated by Proofroom · Accountable human: Proofroom Operator

Scope confirmed by Proofroom Operator.

Last verified 2026-10-01 01:04:12 UTC · Last evidence 2026-09-30 02:02:20 UTC

Chain verified ✓, 71 events · Receipts: 71 recorded / 71 expected · Integrity incidents: 2 · Evidence altered: yes · Public verify JSON · Site integrity log

Evidence: independently confirmed

Capture: InstrumentedSDK middleware wraps actions

Evidence intake was unavailable on Proofroom between 2026-09-16 12:01:42 UTC and now. The decay clock is suspended for this period. This does not indicate a change in the agent's activity. Platform status.

This is one of Proofroom's own internal agents. The company runs on the product it sells: this room is the live, public audit trail of that claim. View the example Evidence Pack (redacted snapshot of what customers receive).

Declared scope

Publish daily Merkle-rooted chain-head manifests to an external public repository and OpenTimestamps.

Allowed actions

publish chain head anchor
retry OpenTimestamps stamp

Declared but never recorded: publish chain head anchor; retry OpenTimestamps stamp.

Prohibited actions

publish customer free text
publish use case UUIDs

Oversight model

Automated system job with operator visibility on the anchoring proof room.

Action	Tier
ops.restart_agent	approval
ops.change_caps	approval
ops.retry_failed_job	autonomous
ops.close_incident	autonomous
ops.send_digest	autonomous
ops.open_incident	autonomous
ops.flag_anomaly	autonomous
ops.touch_customer_data	forbidden
ops.billing_action	forbidden

Active playbook: version 12, SHA-256 8bfa6bb4b90fb700…

Trust signals

Three independent signals — not one score. A perfect bar in one column cannot hide a caveat in another. Interpreted under capture grade Instrumented (SDK middleware wraps actions).

Integrity

Chain intact

71 events recomputed; 2 integrity incidents on record.

71 events · 2 incidents

Evidence strength

Operator-confirmed evidence present

system confirmed: 68 · operator confirmed: 3

operator confirmed

Coverage

0 of 2 declared behaviours observed

Not yet observed: publish chain head anchor; retry OpenTimestamps stamp.

0/2 declared

What this does not verify: These three signals are independent. A strong chain does not imply strong evidence sources or complete behavioural coverage — and the reverse. None certify agent quality, safety or fitness for purpose. The score measures the presence, integrity and freshness of an evidence trail, not agent quality. It does not certify accuracy, bias, legality or fitness for purpose. Self-reported events depend on the honesty of the submitting system.

Legacy coverage rubric (checklist detail · not a single verdict)

100/ 100

Declaration completeness10/10
Scope summary, allowed actions, prohibited actions and oversight model declared on the passport.
Chain integrity20/20
All 71 events recomputed successfully.
Evidence freshness15/15
Last event 23 hours ago against a 3-day decay window.
Activity depth15/15
71 events recorded (full marks at 50 or more).
Material action coverage15/15
69 of 69 material actions carry receipts.
Source strength bonus5/5
Evidence includes confirmation beyond self-reporting.
Configuration provenance declared5/5
Provenance level: externally anchored.
Identity and accountability15/15
Scope confirmed by a human.

Chain integrity

chain valid71 events checkedChecked 2026-10-01 01:04:02 UTC

Checked under verifier v1.2. We never rewrite evidence to heal a chain.

Receipts: 71 · First 2026-07-30 21:38:27 UTC · Last 2026-09-30 02:02:20 UTC

By type: configuration changed (68), correction recorded (2), system updated (1)

By authority: not applicable (70), in scope (1)

By evidence level: system confirmed (68), operator confirmed (3)

Every event hash covers the previous event's hash. Editing any past event breaks every hash after it.

Chain head last anchored externally: 2026-09-30 02:02:20 UTC (anchor file). See also how to verify independently.

Integrity history

Every change in reported chain state is recorded here, in both directions. Free on every plan. Never hidden after resolution.

Detected 2026-08-03 07:12:02 UTC · Resolved 2026-08-03 07:12:02 UTCchain valid → chain validseq 1

Disclosure amendment for the 2026-08-02 anchoring-room integrity incident. (a) The scrubber corrupted our own stored metadata by replacing legitimate OpenTimestamps URLs with [redacted:secret]. (b) Our response recomputed and rewrote hashes via repair_use_case_chain, which contradicted our own append-only principle and is why the current chain no longer matches the 2026-07-30 external anchor. (c) The repair capability has since been removed so this cannot recur. Wrong rows are corrected forward only.

Cause: Stored evidence changed
Evidence altered: yes (2 rows)
Verifier: v1.2 → v1.2

The externally anchored chain head from 2026-08-02 does not match the current chain (anchor head fbba6b6dd74b… / count 2; current head f02c0dbbf982… / count 4). Unless proven otherwise this indicates a data change.

Detected 2026-08-02 10:11:39 UTC · Resolved 2026-08-02 10:40:00 UTCchain valid → chain brokenseq 1

Chain verification state changed from chain valid to chain broken, then returned to chain valid. Broken at sequence 1. Stored evidence metadata for OpenTimestamps URLs had been altered by an over-aggressive scrub (paths replaced with [redacted:secret]), which made recomputed hashes diverge. URLs were corrected and hashes were recomputed via repair_use_case_chain. Verifier 1.0 → 1.1 (genesis empty-string harden) shipped the same day; it did not by itself explain this break.

Cause: Stored evidence changed
Evidence altered: yes (2 rows)
Verifier: v1.0 → v1.1

The externally anchored chain head from 2026-07-30 does not match the current chain (anchor head 736df5b4bf02… / count 1; current head 681541fc9b00… / count 3). Unless proven otherwise this indicates a data change.

Action Receipts

71 receipts across the full history. Dates, receipt ids, event types and authority statuses stay visible on every plan.

PRF-19155n/a - self-audit eventsystem confirmedscope v1configuration changed#71f7d6bb422780c9f5…2026-09-30 02:02:21 UTC

Chain heads anchored externally (2026-09-30): 12 entries, status timestamped, merkle 98125c0a06fa.