Sessions, Resume, and Compaction

Claude Code persists transcript data to project-scoped files and uses explicit path logic for transcripts, session directories, and sub-agent logs.

This lets long-running work survive beyond a single terminal view.

The resume flow is not a naive list of every conversation. It filters resumable sessions, supports worktree-aware lookup, and warns when a conversation belongs to a different directory.

That protects users from resuming context in the wrong project and making confusing edits.

Transcript persistence alone is not enough. The active prompt still needs to fit within model limits, which is why compaction and budget handling sit next to session logic in the broader system.

In practice, sessions and compaction are two halves of the same durability story.