Regenerate advanced and restart expectations through the shipped macOS arm64 SEA runtime built from 0521815d45. Real delivery-accepted events now record sessionFormatVersion 3 in the five V3 logs and advanced SDK notifications. Restart result.json and requests.json regenerate identically. Preserve all five V2 predecessors byte-for-byte from b2b300f9; no production, migration, launcher, or test changes.
Evidence (macOS arm64): pnpm exec tsx scripts/build-exe-for-python-sdk.ts --targets node24-macos-arm64 passed, including the full pnpm build. file dist-exe/deepseek-harness-sdk-runtime-macos-arm64 reports Mach-O 64-bit executable arm64.
For each SCENARIO=sdk-snapshot,sdk-restart: PYTHONDONTWRITEBYTECODE=1 PYTHONPATH=python/sdk/src:python/sdk-runtime/src /Users/cty/dsh-deploy/.agents/worktrees/sp-kv-sdk-evidence/tmp/py-sdk-venv/bin/python scripts/smoke-python-runtime.py --exe dist-exe/deepseek-harness-sdk-runtime-macos-arm64 --scenario SCENARIO --update-snapshots passed; the same two commands without --update-snapshots passed.
PYTHONDONTWRITEBYTECODE=1 PYTHONPATH=python/sdk/src:python/sdk-runtime/src uv run --no-project --python /Users/cty/.local/share/uv/python/cpython-3.14.5-macos-aarch64-none/bin/python3 --with pytest --with pydantic>=2.12,<3 python -m pytest python/sdk/tests/test_smoke_model.py -q: 28 passed. Earlier helper invocations lacked pytest or SDK imports; corrected environment passed without source changes. git diff --quiet b2b300f9 -- scripts/snapshots/python-sdk-single-exe/**/*.v2.jsonl and git diff --cached --check passed.
Restore all 147 historical canonical fixtures changed by the lower branch to exact shared base 220ff708e3628a9be46d9747d09af6d8cd742f0d bytes (145 V2 and two V0). All 180 committed V0/V1/V2 canonical files now have zero diff against that base, including unchanged Python, test-support and preview sources.
Preserve corrected lower writer bodies in 146 V3 successors across 119 owner directories: replace 135 unreleased V3 counterparts and add 11 siblings. Change only each copied Session header version; preserve all body bytes, raw model streams, inline images, IDs, references and historical delivery generation markers. Remove two unshipped V2 additions after creating their V3 sibling: record-suite/rec-pin and empty-response-retry-current.
Keep six explicitly historical snapshot owners pinned with no V3 sibling. Restore the two pre-step V0 record child sources without synthesizing current output. Fix seven embedded Session header versions in exactly five test-support behavior owners whose output filenames already select V3. Leave protocol expectations, shared references, sidecars, consumer scripts and production migration/normalization code untouched.
Validation: purpose-built temporary Python inventory and verifier checked 337 canonical headers, 3714 successor JSON rows, message roles, contiguous child roles, exact successor bodies, all 180 historical base bytes and zero git diff, noncanonical JSONL immutability, six retained owners and six unchanged preview fixtures. git diff --cached --check passed. Temporary generators removed. Strict migration, native refresh and replay remain pending parent integration; unsupported pre-step sources are reported separately.
Tianyi Cui