Source Intelligence

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

All of v2.1.246 Home All releases olderv2.1.245 v2.1.247newer
Claude Code v2.1.246

The row-based and archive file-sync engines are gone; old records turn sync off

You'll notice
Useful4 Signal3
File Sync

Cloud sessions recorded by the old sync engines stop syncing and tell you to start a new one.

What

A directory whose cloud-session record was written by the older rows or archive sync engines will no longer resume syncing. Attaching to such a session shows a line beginning "File sync is off for this session here" and tells you to start a new cloud session from that directory. This applies to everyone on this build; no switch guards it.

Details
  • The record reader used to return rows, unseeded and archive alongside git; it now returns an "unsupported" result naming the engine, and any engine it does not recognise gets the same treatment. The string archive no longer appears in the bundle.
  • Attach registers a stopped engine with reason engine_unsupported, and the running loop reports the same.
  • Backing that stopped state is a do-nothing engine (activate, messageSent, afterResult, laneChanged, afterConnect, afterDisconnect all empty; send and drain resolve empty) plus a one-shot gate that answers "do not send" once with the reason, so the first message explains itself rather than failing silently.
Evidence

File sync is off for this session here: its local record was written by a sync engine this version of Claude Code does not have. Start a new cloud session from this directory to sync it., sync engine this version of Claude Code does not have

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

See this entry in the whole of v2.1.246 →