Claude Code Now Supports a One-million-token Context Window and Provides Session Controls Like Compaction, /rewind, and Subagents.

TL;DR: A larger context enables longer, continuous workflows but increases context rot and requires deliberate session management.

• Scope/Impact: Allows multi-file, end-to-end tasks in a single session but can dilute attention across more tokens.
• ATT&CK-style techniques: N/A (product behavior); operational techniques include compaction and session isolation via subagents.
• Artifacts/Controls: /usage for telemetry, /rewind to drop later turns, compaction summaries when nearing limits.
• Mitigation/Workflow: Start new sessions for distinct tasks, use /rewind to revert faulty paths, use compaction when older state is still useful, and employ subagents for isolated subtasks.
• Uncertainties: Degree of information loss from automatic compaction and the practical thresholds where context rot materially degrades outputs.

URL: https://claude.com/blog/using-claude-code-session-management-and-1m-context