Skip to main content
[PARTIAL], and more precisely split than the name suggests. There are two unconnected things called “replay” in the current codebase. Conflating them would overclaim what either one does.

​
1. POST /replay (what the SDKs and HTTP API expose)

This is what client.replay.replay(transaction_id) actually calls. Its real implementation, ExecutionTrustApplication.replay() (packages/runtime/src/ExecutionTrustApplication.ts:142-171): 
async replay(businessTransactionId: string): Promise<{
  businessTransactionId: string;
  trustRecordHash: string;
  verified: boolean;
}> {
  const trustRecord = await this.trustRecords.findByTransactionId(businessTransactionId);
  if (!trustRecord) throw new Error("Execution Trust Record not found.");
  const verified = await this.crypto.verify(trustRecord);
  return { businessTransactionId, trustRecordHash: trustRecord.trustRecordHash, verified };
}
This re-verifies the Trust Record’s cryptographic signature, it does not reconstruct or re-execute anything. [AVAILABLE], but narrower than “replay” implies: it’s a signature recheck with a replay-shaped response, not deterministic execution reconstruction.

​
2. packages/replay (the deterministic reconstruction engine)

A separate, real package: ReplayEngine, ReplayPipeline, ReplayExecutor, ReplayBuilder, proven deterministic regardless of input order (ReplayDeterminism.test.ts, “should produce identical output regardless of input order”; ReplayEngine.test.ts; 9 tests total). This corrects a previous version of this page: ReplayEngine.replay() genuinely re-evaluates the original policy against the recorded signals, using a real PolicyEngine, not just a signature or hash recheck: 
// packages/replay/src/ReplayEngine.ts:38-62 (abridged, real source)
const policyDecision = this.policyEngine.evaluate(policy, signals);
const replayedDecision = { ...recordedDecision, outcome: policyDecision.outcome, ... };
const matches = recordedDecision.outcome === replayedDecision.outcome;
Verified live, examples/tutorials/06-replay/run.ts: it prints a Recorded Decision and a Replayed Decision and reports Replay Match: true when they agree. This is real semantic re-evaluation, scoped to one execution’s decision outcome, not the fuller claim below.
Still confirmed disconnected: nothing in packages/api or packages/runtime imports @parmana/replay. This engine is not reachable through POST /replay or any other route today, and it only handles trustRecord.executions[0], one execution, not the whole record. It’s real, tested, standalone library code, not yet wired into the runtime or the HTTP surface.

​
What CLAIMS.md’s “semantic verification” Future Claim still withholds

CLAIMS.md §4 lists “Replay semantically verifies every trust artifact” as a Future Claim, not a Supported one. That claim is broader than what ReplayEngine does today: “every trust artifact” implies re-evaluating every execution across a record and every artifact type, not one execution’s decision outcome. ReplayEngine’s real, narrower behavior above doesn’t contradict CLAIMS.md, it’s evidence toward a scoped piece of that future claim, not the whole of it. See Roadmap.