{"version":"2.1.281","anchor":"artifact-patch-publishes-can-send-per-file-preconditions-and","canonical_anchor":"artifact-patch-publishes-can-send-per-file-preconditions-and","heading":"Artifact patch publishes can send per-file preconditions and report precondition_failed conflicts","tier":null,"area":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.281\/e\/artifact-patch-publishes-can-send-per-file-preconditions-and","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.281","markdown":"### Artifact patch publishes can send per-file preconditions and report precondition_failed conflicts\n\nArtifact patch publishes can now send per-file checks and report which files conflicted when a check fails\n\n**What**\n\nWhen an artifact is published as a patch (only the changes, not the whole thing) and the publish is not forced, Claude Code now sends a set of preconditions for each file when the Artifact tool provides them. A precondition is a check that the file on the server is still the version it was based on. If the server refuses with a `precondition_failed` conflict, Claude Code now reads out which files conflicted. Its conflict telemetry records `if_match_sent` and `conflict_paths`.\n\n**Why**\n\nIf someone else changed the same files first, a patch publish can now be stopped instead of overwriting their work, and the conflict names the exact files involved. The related server-side flag `tengu_cobalt_plinth_fern` has read on both for this site's account and for an anonymous baseline, in readings not yet taken under this release.\n\n- Flag `tengu_cobalt_plinth_fern`: On for this account, and not off by default (read for one account on one subscription tier against v2.1.281; this account: on, anonymous baseline: on, compiled default: on) These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release."}