{"version":"2.1.307","anchor":"transcript-backfill-gets-a-budget-abort-signal-and-telemetr","canonical_anchor":"transcript-backfill-gets-a-budget-abort-signal-and-telemetr","heading":"Very long sessions may skip uploading their earlier history","tier":"notice","area":"Session Transcripts","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.307\/e\/transcript-backfill-gets-a-budget-abort-signal-and-telemetr","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.307","markdown":"### Very long sessions may skip uploading their earlier history\n\nClaude Code now refuses to upload earlier session history when a transcript has too many lines since its last compaction\n\n**What**\n\nA session's transcript is the saved record of the conversation. Claude Code can upload the earlier part of a transcript after the fact, a step called a backfill. Before, that step was limited only by how many lines it could read.\n\nThe backfill read now has a shared limit and can be stopped partway through. It also refuses a transcript that has too many lines since the last compaction boundary. Compaction is when Claude Code summarises the earlier conversation to save space. Claude Code now records whether each backfill read succeeded.\n\n**Why**\n\nIn practice, very large sessions may have their earlier history left out of the upload.\n\n- Area: Session Transcripts\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 2\/5\n- Scope: individual\n- Heads-up: no"}