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 v2.0.58 Home All releases olderv2.0.57 v2.0.59newer
Claude Code v2.0.58

Background Model Reference Updated

What: Claude's background information now references Opus 4.5 as the most recent frontier model instead of Sonnet 4.5.

Details:

  • Affects Claude's self-awareness when discussing model capabilities
  • Evidence: Jy3 = "Claude Opus 4.5" at line 509270 in v2.0.58

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

See this entry in the whole of v2.0.58 →