Claude Code noticeably slow all day (2026-04-08)

Summary

Claude Code has been noticeably slow throughout the day on 2026-04-08. Routine operations and agent responses are taking much longer than usual.

Concrete example

A sub-agent spawned to write a plan file took ~20 minutes and ended up corrupting the target file by leaking its internal reasoning into a Write tool call (meta-commentary like "I'm realizing the user is getting impatient..." appeared inside the file content).

Impact

• Long waits for simple operations
• At least one corrupted file from a long-running agent
• General degradation in interactive responsiveness

Environment

• Date: 2026-04-08
• Model: Claude Opus 4.6 (1M context)
• Platform: Linux (VSCode extension)

Filing on behalf of an active user who has been experiencing this all day.