SPEC — Colony transcript replay (E-E4)

Status: SPEC. Awaits /lab-team-review. Ship gate: MERGED VERDICT.

Purpose

Give a stranger the ability to replay a live-recorded colony transcript from a chosen seed AND independently verify UNI's on-tick blanket contract — the four checks in SP.Sim.Verifier.check_log/1 (per docs/observability/evidence_log.md).

The primary claim this surface makes is: the seed alone is enough to reproduce our verdict. That is the "receipts beat rhetoric" invariant applied to public science.

Deployment shape

• Read-only web surface (behind cloudflared).
• Serves a directory-listing UI over evidence/transcripts/<seed>/ for a fixed set of blessed seeds.
• For each seed, serves:
  • transcript.jsonl — the per-tick blanket log (schema at docs/observability/evidence_log.md).
  • meta.json — genome sha, code sha, world seed, kin ids, run start/end.
  • A "verify with mix sp.verify" instruction with a copy-paste command line.
• Also serves SP.Sim.Verifier.check_log/1 outputs as pre-computed sidecar verify.txt files for each transcript, so a reader doesn't need to run mix at all to see the four-check result.

Trust model

• Every transcript is immutable once published (append-only mount).
• The manifest at production/schemas/public_manifest.schema.json names every published transcript's sha.
• A reader who wants to verify:
  1. Downloads transcript.jsonl + meta.json.
  2. Runs mix sp.verify --log path/to/transcript.jsonl --meta path/to/meta.json.
  3. Compares output to the sidecar verify.txt (byte-for-byte should match).

Non-goals

• Does NOT expose the LIVE colony's transcript in real time. That's a subscribe surface; this is playback of blessed frozen runs.
• Does NOT expose intermediate tensor state. Only the on-tick blanket log.

Test coverage the plan owes

• test/production/uni_public_mcp_transcript_replay_test.exs:
  • Every listed transcript has a matching verify.txt whose sha matches the current SP.Sim.Verifier.check_log/1 output.
  • manifest.public.sha matches computed sha.

Cross-references

• docs/PUBLIC_REPRODUCIBILITY_BUNDLE.md — the human-language entry.
• docs/observability/evidence_log.md — the frame schema.