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.
The Bash tool description now explains run_in_background more directly and removes stale advice to read output later immediately. Claude Code also includes stronger guidance to avoid foreground sleep and use background commands or Monitor for waiting.
Evidence
Background command guidance (search for "run_in_background runs the command detached" and "Foreground sleep is blocked")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.