Source Intelligence

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

All of v2.0.65 Home All releases olderv2.0.64 v2.0.66newer
Claude Code v2.0.65

Headless Profiling System

What: Built-in performance profiling for SDK/headless usage with turn-level metrics. How to enable:

export CLAUDE_CODE_PROFILE_STARTUP=1  # Enable verbose logging

Details:

  • Tracks key checkpoints: system message generation, query start, first response chunk
  • Reports metrics via telemetry for 5% of sessions
  • Evidence: e30(), p1A(), A80() functions at lines 445732-445745

See this entry in the whole of v2.0.65 →