Summary

Close the remaining DRY_RUN_PAYLOAD_EXCLUSIONS tail and ship the WRITE_SANDBOX coverage audit (#122). Final patch before 0.4.0.

Entries to resolve (per-entry decision)

For each remaining exclusion, decide either "write a PAYLOAD_CASE" or "keep with documented technical reason":

• adimages.add — image-data fixture; likely keep with reason "media payload".
• advideos.add — same.
• vcards.add — large contact-card payload; likely keep with reason "contact-card complexity".
• feeds.add — WSDL parser limitation per current comment; verify and keep.
• retargeting.add — typed --rule fixtures; write PAYLOAD_CASE if feasible.
• reports.get — TSV endpoint; keep with reason "custom non-RPC contract".
• agencyclients.add — runtime-deprecated; keep, link to RUNTIME_DEPRECATED_METHODS.
• adextensions.add — callout-only currently; write PAYLOAD_CASE.
• dynamicfeedadtargets.*, strategies.* — already covered by focused tests; either add PAYLOAD_CASE entries that mirror those tests, or keep with explicit "covered by test_dry_run.py::<test>" reason.

Plus #122

Build scripts/sandbox_write_audit.py per #122 detailed plan. Output Markdown table to stdout + JSON artifact at build/sandbox_audit.json. CI gate.

Acceptance criteria for closing this issue

• Every remaining entry in DRY_RUN_PAYLOAD_EXCLUSIONS has a documented technical reason — not "no fixture written".
• nested_schema_violations == [].
• summary.schema_parity_ok == true.
• python3 scripts/sandbox_write_audit.py exits 0; every WRITE_SANDBOX row classified.
• 0.4.0 — extend WRITE_SANDBOX integration coverage per-method #122 closes with a Markdown audit table in the closing comment.
• Close mutating dry-run payload schema exclusions for 0.4.0 #127 closes with the final exclusion summary.

Refs: parent #127, #122.

Contract source rule

When this issue touches API contracts, V4 Live methods, request bodies, response shapes, safety classification, or CLI command payloads:

• Treat official Yandex Direct docs and safe live probes as the only authoritative sources for wire shape.
• Do not treat issue examples, guessed param names, or vendored method registries as authoritative by themselves.
• If official docs are missing, 404, ambiguous, disabled, or contradict this issue, stop implementation and record the docs drift before coding.
• Public CLI must stay typed and canonical: no public --json passthrough for user-facing input.
• Mutating or financially sensitive V4 commands stay dry-run-only unless the issue explicitly says otherwise after verification.
• Update direct_cli/v4_contracts.py source status (confirmed-live, docs, undocumented) and add focused tests for exact request bodies.

Closure checklist

• Merge the implementation that adds scripts/sandbox_write_audit.py, the scripts/test_sandbox_write.sh --audit mode, and the audit/coverage tests.
• Confirm python3 scripts/sandbox_write_audit.py exits 0 and writes build/sandbox_audit.json.
• Confirm the audit output has 83 WRITE_SANDBOX rows: 80 PASS and 3 NOT_COVERED linked to Follow up: classify clients.update and v4tags update live sandbox gaps #213.
• Confirm python3 -m pytest -q tests/test_api_coverage.py tests/test_smoke_matrix.py tests/test_sandbox_write_audit.py passes.
• Confirm python3 scripts/build_api_coverage_report.py reports summary.schema_parity_ok == true and schema.nested_schema_violations == [].
• Add the Markdown WRITE_SANDBOX audit table to 0.4.0 — extend WRITE_SANDBOX integration coverage per-method #122 as the closing comment.
• Add the final DRY_RUN_PAYLOAD_EXCLUSIONS summary to Close mutating dry-run payload schema exclusions for 0.4.0 #127 as the closing comment.
• Close 0.4.0 — extend WRITE_SANDBOX integration coverage per-method #122 and Close mutating dry-run payload schema exclusions for 0.4.0 #127 after their closing comments are posted.
• Close 0.3.9 — DRY_RUN_PAYLOAD_EXCLUSIONS tail + WRITE_SANDBOX audit #138 after the implementation is merged and the checklist above is complete.

Non-blocking follow-up: #213 tracks the intentionally deferred live sandbox scenarios for clients.update, v4tags.update-banners, and v4tags.update-campaigns.