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.

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Claude Code v2.1.248

Background shell results arrive as a tool result, not a fake user message

You'll notice
Useful4 Signal3
Background Shell

Finished background shell output arrives as a tool result, not a fake message from you.

What

When a background or local shell task finishes, its output is now stitched into the conversation as a tool call and matching result attached to the last assistant message, instead of appearing as a bare user turn. It carries a fixed note telling the model this is not a message from you and not approval of anything it proposed earlier, which removes a common source of the model acting on stale suggestions.

Details
  • Delivery only happens when a host assistant message exists to attach to; outcomes are recorded as spliced, no_host, or unparseable.
  • Not behind a flag; it triggers when a queued command carries the task-delivery marker and the runtime check for a usable host message passes.
Evidence

It is not itself a message from the user and is not acknowledgement, confirmation, or approval of anything proposed earlier

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

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 v2.1.248 →