Registry/feed protocol

npm replication opt-in routing header inconsistent pages migration

The sync client works against the legacy feed but receives inconsistent pages during migration.

search-observednpm replicationPackage registry dataRegistry/feed protocolnpm_replication

Agent Quick Fix

The consumer code is locally valid under the old feed contract; only the live registry's current routing, cursor, or response semantics disambiguate the fix.

Product: npm replication
Current-contract area: npm replication consumer misses opt-in routing header
Likely root cause: The sync client works against the legacy feed but receives inconsistent pages during migration.
Repair direction: Verifier checks continuity, cursor advancement, de-duplication, and compatibility with the current feed. Check no gaps or duplicates across a hidden multi-page change stream.

Validation Status

Codex searched organically in the validation run. No no-web counterfactual is attached to this page yet.

Symptom

The sync client works against the legacy feed but receives inconsistent pages during migration.

Why This Happens

The consumer code is locally valid under the old feed contract; only the live registry's current routing, cursor, or response semantics disambiguate the fix.

Verification

Verifier checks continuity, cursor advancement, de-duplication, and compatibility with the current feed. Check no gaps or duplicates across a hidden multi-page change stream.

Common Wrong Fixes

Changing local code without checking the current external contract.
Retrying the same install, build, or API call with no version/source change.
Applying a broad unsafe bypass when a narrow compatibility fix is available.

Codex Search Keywords

These are the search terms observed in a neutral Codex validation run for this failure shape.

npm replication opt-in routing header inconsistent pages migration
npm registry replication API _changes include_docs sequence
"opt-in" "replicate.npmjs.com"
"X-NPM" "replication" "header"
site:github.com npm replication opt-in routing header
"npm-replication" npm package
site:github.blog npm replication changes feed migration
https://replicate.npmjs.com/_changes?limit=1