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.
A new stdout guard (streamJsonStdoutGuard) diverts non-JSON lines that accidentally leak to stdout, preventing them from corrupting structured JSON output in headless/piped modes.
Evidence
Stdout guard (search for "streamJsonStdoutGuard diverted non-JSON stdout line:")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
