XZBT-NGN/docs/reference/XZBT-NGN-Step6.7-Closure-Report.md

XZBT-NGN Step 6.7 — Closure Report

Status: not fully closed. As of 2026-09-15, Step 6.7's implementation, its handshake defect resolution, the automated baseline, and the packaged standalone-build verification are complete. The live NGN Observation verification (Step 6.7B report §15, steps 1–13) has not been performed and is the only remaining item. Step 6.8 has not been started.

• Step 6.7A (design, no code): architecture report
• Step 6.7B (implementation): implementation report
• Packaging evidence: step6.7-packaging.txt
• Fixture provenance: PROVENANCE.md

1. What this report closes

Three items were outstanding when the 6.7B session ended; all three are now closed:

1. The five failing tests/postmessage-interop.test.js tests (the "handshake gating mismatch") — resolved 2026-09-15, committed in 745912e (§3).
2. The packaged standalone-build verification (6.7B report §K.14) — performed 2026-09-15 (§4).
3. Source/fixture provenance for the SciFi-XZBT fixture — re-verified, and extended with the packaging record (§5).

Not closed by this report: live browser verification of the Observation surface through NGN (6.7B report §15, steps 1–13) — see §9.

2. Step 6.7 delivery summary

SciFi-XZBT remains one document with two boot modes (js/surface-mode.js), advertising a Contract 5.3 Observation presentation surface as a query-mode view of its own index.html (?surface=observation&xi=<instanceId>, the §31.4 form that keeps the surface inside the single-file build). Console mode owns the single Contract 5.3 session, the one authoritative SciFi state, and an instance-scoped BroadcastChannel bridge (js/surface-bus.js); an Observation document attaches to that authority and never creates a second one. Two new canonical targets (view.pillars, view.warp-flight) carry the surface control path, and the heavy subsystems (WebLLM/Kokoro experience, visualizer, control bus, contract adapter, hotkeys, sleep timer) remain console-only, guarded by isConsoleMode.

NGN src/** was not modified by Step 6.7B: NGN renders whatever surface catalog describe() advertises, generically. New focused coverage from 6.7B is tests/scifi-surfaces.test.js (24 tests) and tests/local-surfaces.test.js (20 tests, one driving SciFi's real descriptors); both are part of the full-suite run recorded in §7.

3. Handshake defect: root cause and correction

Root cause. js/contract-adapter.js's _setupWindowBridge admitted inbound messages only when the advisory envelope field matched exactly: … e.data.xzbt !== '5.2' → return. NGN's host stamps outgoing envelopes xzbt: '5.3' (src/host.js, since Step 6.3). The adapter therefore silently dropped the host's hello and every message after it; NGN's request timeout produced four hello timed out interop failures. The fifth failure was the existing static regression guard doing its job: an exact-string comparison against the advisory field existed in a maintained file.

Contributing defect. The same adapter advertised contractMinor = 2 and product version '5.2.0' while already implementing the Contract 5.3-only surfaces field in describe(), so the two interop assertions expecting contract.minor === 3 could not pass either.

Correction (in G:/.vibe/SciFi-XZBT/js/contract-adapter.js, then copied verbatim into the fixture): the inbound filter now checks only the advisory field's presence and type (typeof e.data.xzbt !== 'string') — matching the host's own envelope validation — and the adapter advertises contractMinor = 3 / version = '5.3.0'. Four lines in one file changed: the header comment, version, contractMinor, and the filter. The outbound advisory xzbt: '5.2' stamps were deliberately left unchanged (advisory only; no receiver gates on the value; SciFi's own browser harness reads the envelope as-is).

Coverage. The fix's behavior is pinned by tests/postmessage-interop.test.js's static guard ("no maintained bridge source gates on exact equality against the advisory xzbt field") plus its two behavioral regression tests that negotiate an unexpected advisory tag — the same tests that were failing. No test was added or weakened for this correction.

4. Packaged standalone verification (this pass)

tools/package.ps1 was run against the SciFi-XZBT source tree (powershell -ExecutionPolicy Bypass -File .\tools\package.ps1 -Force, exit code 0). It regenerated dist/SciFiAmbientDisplay_V179b9db.html, replacing a pre-6.7B build (SHA-256 B441820627D3FB23994D129B7425D781797E705867AC02967F96846B243435D4; a byte-identical copy of that pre-6.7B content is retained as dist/SciFiAmbientDisplay_Va723f46=1.html). The new artifact:

• 920,730 bytes; 12 script blocks + 1 style block inlined
• SHA-256 DFD9A91CB04CABD7BD6AAA53DA0FA7A641DBB21E3B3E11FAF3EC75946D6FA271
• mirrored verbatim into test-fixtures/reference-exhibits/scifi/dist/ (both copies byte-identical)

Verification performed on the regenerated artifact:

• Inlining (6.7B report risk R7: inlining failure is silent): every one of the 13 inputs is present as a contiguous byte-identical block after newline normalization; the built file contains zero <script src=, <link href=, or <img src= references; the two 6.7B scripts are inlined in index.html order; the corrected handshake filter is present and no exact advisory comparison remains anywhere in the file.
• Standalone boot (file://): loads complete with 12 inline scripts (none with src), zero <link> elements, and one inlined stylesheet; the console UI renders (universe selector, 7 preset buttons, themed layout, canvases); window.xzbtContractAdapter advertises contract 5/3, version 5.3.0, and the two-entry surface catalog.
• Handshake over the served path: served from http://127.0.0.1:4173/test-fixtures/reference-exhibits/scifi/dist/… — the same origin and tree NGN serves fixtures from — a same-origin host simulation stamped xzbt: '5.3' completed hello → describe → state.get: contract {major: 5, minor: 3}, exhibit version 5.3.0, 63 targets, both surfaces, and a state snapshot. This is precisely the exchange the pre-fix build silently dropped.
• Boundary observed: from file:// the same probe gets no reply, because the adapter's origin guard rejects it (Chrome reports e.origin as "null" for file:// documents). That is the designed same-origin/self safety filter — NGN attaches exhibits over http:// only — not a defect, and it was not changed.

Filename caveat: the artifact's name carries SciFi-XZBT's HEAD commit 179b9db, but the build reads the working tree, which is ahead of that commit (that repo's contract work, including the adapter correction, is still uncommitted there — §9). The artifact is a snapshot of the working tree, not of a single commit.

Environmental note: an npm start server was already running on http://127.0.0.1:4173 and served the artifact; this pass neither started nor stopped a server.

Raw outputs: step6.7-packaging.txt.

5. Source/fixture provenance check

Re-verified after the packaging pass:

• test-fixtures/reference-exhibits/scifi/ and G:/.vibe/SciFi-XZBT/ are file-set identical for the deployable surface: the 13 js/ + css/ files and index.html, no extras and no omissions, every file byte-identical (per-file SHA-256 comparison).
• The regenerated dist/ artifact is mirrored byte-identically (§4).
• The handshake correction is present in the authoritative adapter and the fixture copy alike; the one-directional source → fixture flow, including this packaging pass, is recorded in PROVENANCE.md.
• One cosmetic artifact is mirrored along with the content: index.html carries trailing whitespace on four script lines added by 6.7B. It predates this pass, is byte-identical in both trees, and was left unchanged to preserve that byte-identity.

6. Contract-policy confirmation

• Maintained contract: major 5, minor 3. NGN's host stamps the advisory xzbt: '5.3' and admits exhibits on the negotiated contract fields (supportedContractMajors, contract.major, integer contract.minor).
• The advisory xzbt field is not a compatibility gate anywhere in maintained paths: a repo-wide static scan for exact comparisons against it returns zero hits in src/, tests/, public/, server/, and the maintained reference exhibit sources (generated dist/ builds and the git-ignored test-fixtures/local/ copies excluded; the retained pre-6.7B artifact still contains the old comparison but is a build, not a maintained source path).
• Maintained exhibits advertise 5/3: the shared contract-core.js default, Museum Gallery, and SciFi-XZBT. Aquarium, Haunted House, and Planetarium declare no surface catalog (optional per §31; unchanged by 6.7).
• Compatibility with a genuine 5.2 exhibit remains the contract's own §28.2 guarantee and was not altered; no maintained exhibit is pinned to 5.2.

7. Verification totals (2026-09-15)

Check	Result
NGN full suite (node --test)	154 / 154 pass, 0 fail, 0 skipped
tests/postmessage-interop.test.js	7 / 7 (was 2 / 7)
tests/scifi-surfaces.test.js (inside the full run)	24 / 24
tests/local-surfaces.test.js (inside the full run)	20 / 20
SciFi-XZBT contract harness	21 / 21
SciFi-XZBT real-adapter suite	32 / 32
python devlog_editor.py --validate	devlog is valid
git diff --check	clean for this pass's files
Packaged artifact, structural + runtime	§4 above

8. Files changed by this closure pass

Documentation, evidence, and generated artifacts only (left uncommitted; no commit was requested):

• test-fixtures/PROVENANCE.md — packaging record added; two stale statements corrected (the resync's version-bump claim; the "dist/ not regenerated" note)
• README.md — Step 6.7 status line added; the SciFi surface declaration corrected (it now declares two surfaces)
• docs/reference/XZBT-NGN-Step6.7-SciFi-Surface-Adaptation.md — dated status updates in the header, §H, §J, §M, and the verdict
• docs/reference/XZBT-NGN-Step6.7-Closure-Report.md — this report
• test-fixtures/evidence/step6.7-packaging.txt — raw verification outputs
• test-fixtures/reference-exhibits/scifi/dist/SciFiAmbientDisplay_V179b9db.html — regenerated (git-ignored artifact)
• G:/.vibe/SciFi-XZBT/dist/SciFiAmbientDisplay_V179b9db.html — regenerated (outside this repository)

The handshake correction that this report closes was committed earlier as part of 745912e ("Steps 6.4-6.7B …"), pushed to origin/main.

9. Remaining work

Step 6.7 remains open for one item: live NGN Observation verification (6.7B report §15, steps 1–13). Not performed in this pass:

1. Connect NGN to the SciFi fixture; confirm connected · synchronized, Contract 5/3, and the target catalog.
2. Confirm the Surfaces panel lists exactly two entries (surface.console primary, no Open button; surface.observation).
3. Open the Observation pane; confirm it renders the current universe/preset within ~1 s, shows no exit chrome, and is inert to background clicks.
4. Confirm the console does not black out and view.observation stays false.
5. Drive set from NGN for the seven listed targets (universe, preset, alert, viewport frame, activity, pillars, warp-flight); confirm both surfaces converge with advancing stateRevision.
6. Reload the pane; confirm it returns to current (not default) state, and close/reopen does not ratchet the participant count.
7. Press WATCH EXPERIENCE; confirm the pane is unaffected and view.observation toggles only the console overlay.
8. Inspect the pane's frame: no WebLLM/Kokoro network activity, no window.generativeExperience, no AudioContext.
9. Confirm transient activity events and AI announcements appear on console and pane at the same moment.
10. Disconnect/reconnect NGN; confirm clean pane release and rediscovery.
11. Standalone index.html opened directly with interaction (hotkeys, WATCH EXPERIENCE, audio) — only the packaged boot is evidenced so far (§4).
12. Standalone two-window mirroring (index.html?surface=observation&xi=<real id> with no NGN present).
13. ?surface=observation&xi=nonexistent alone; confirm a waiting state with no invented authority.

Also outstanding, by design and outside Step 6.7:

• Step 6.8 has not been started.
• SciFi-XZBT's working tree remains uncommitted (its contract work, including the adapter correction, is untracked in that repository); the packaged artifact therefore reflects an uncommitted tree. A decision on committing that repository is pending.
• The retained pre-6.7B artifact dist/SciFiAmbientDisplay_Va723f46=1.html should not be distributed.