Stream-json results from claude -p now document a 'seq' delivery-order field
Results returned in stream-json format (used with claude -p) now have a documented seq field, a delivery sequence number counting how many results the run has numbered before this one, starting at 0. It counts in the order results are written, not the order they were produced, and it still increments even if a particular write fails, so a gap in the sequence means a result was lost. This field is absent from the in-process engine surface and from error results built locally by cloud-relay clients.
This gives consumers of stream-json output a way to detect whether any results were dropped in transit, by watching for gaps in the sequence numbers.
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
* Fixed resumed `claude -p` sessions whose tools all come from MCP servers failing with "At least one tool must have defer\_loading=false"changelog see the edit
Earlier thinking blocks aren't in the prefix, but each thinking block records which thinking block came before it, across turns. You can remove thinking blocks from the start of the history (oldest first), from the end, or all of them. Wha…build-with-claude/preserved-thinking see the edit
Anthropic's documentation has since written up seq, on preserved-thinking.